All-in-one dry development for metal-containing photoresist

Abstract

SOLUTION: To allow process condition management to facilitate the integration of dry development and post-development processing into a single process chamber, eliminating the need for a separate post-dry development bake step during semiconductor manufacturing, and perform thermal dry development and plasma dry development in the same chamber, and enable the operations of thermal dry development, plasma dry development, and passivation (O2 flash processing), or thermal dry development, plasma dry development, passivation, and curing without wafer transfer.SELECTED DRAWING: Figure 3

Description

Cross-reference

[0001] A PCT request form is submitted herewith as part of this application. Each application for which this application claims benefit or priority, as specified in the PCT request form submitted herewith, is hereby incorporated by reference in its entirety for all purposes. BACKGROUND OF THE INVENTION

[0002] The manufacture of semiconductor devices such as integrated circuits is a multi-step process including photolithography. Generally, the process includes depositing materials on a wafer and patterning the materials using lithographic techniques to form the structural features (e.g., transistors and circuits) of the semiconductor device. The steps of a typical photolithography process include preparing the substrate, applying a photoresist by spin coating or the like, exposing the photoresist with a desired pattern to increase or decrease the solubility of the exposed areas of the photoresist in a developer, developing the photoresist pattern by applying a developer to remove either the exposed or unexposed areas of the photoresist, and performing subsequent processing to form features on the areas of the substrate from which the photoresist has been removed, such as by etching or depositing materials.

[0003] The evolution of semiconductor design has been driven by the need to create ever smaller features on semiconductor substrate materials. One challenge in manufacturing devices with such small features is the ability to reliably and reproducibly generate photolithography masks with sufficient resolution. Current photolithography processes typically utilize 193nm ultraviolet (UV) light to expose photoresist. This presents an inherent problem due to the fact that light has a wavelength significantly longer than the desired size of the features formed on the semiconductor substrate. To achieve feature sizes smaller than the wavelength of light, the use of complex resolution enhancement techniques (such as multipatterning) is necessary. Accordingly, there is great interest in and research being done towards the development of photolithography techniques that utilize short wavelength light (such as extreme ultraviolet radiation (EUV)) having a wavelength in the range of 10nm to 15nm (e.g., 13.5nm).

[0004] However, EUV photolithography processes can present challenges such as low throughput, light loss during patterning, and metal cross - contamination due to metal gas release. Accordingly, improved EUV photoresist processes that more efficiently produce materials with desired properties are still sought after.

[0005] The description of the background art provided herein is for the purpose of generally presenting the background of the present disclosure. The achievements of the inventors named herein, to the extent that they are described in this background art, are not to be recognized as prior art to the present disclosure, either explicitly or implicitly, including any aspects of the description that cannot be normally considered prior art at the time of filing as well as those aspects that are not recognized as prior art to the present disclosure within the scope described in this background art.

SUMMARY OF THE INVENTION

[0006] The present disclosure relates to methods and apparatuses for the integration of dry development processes into the same processing chamber. In some embodiments, the present disclosure relates to methods and apparatuses for the integration of dry development and post-dry development processes into the same processing chamber. This integration of processing the surface of a metal-containing photoresist improves throughput, reduces wafer handling, and improves the efficiency of semiconductor manufacturing through higher wafer productivity and better lithography control. Also, the integrated process improves the yield / defect performance of the device. Post-dry development processing includes passivating with a plasma. Additionally or alternatively, post-dry development processing may include curing. Post-dry development processing that is passivated and / or cured by a plasma in a flash process may all be performed in a single processing chamber in conjunction with dry development, eliminating the need for post-dry development baking that would otherwise need to be performed in a separate chamber or tool. Also, the integrated method achieves surface smoothing and alleviates gas evolution of contaminants by passivation.

[0007] Accordingly, in a first aspect, the present disclosure includes a method for performing dry development and passivation of a metal-containing photoresist all within one processing chamber. In some embodiments, the method includes providing a patterned metal-containing photoresist on a semiconductor substrate within a processing chamber, thermally dry developing the patterned metal-containing photoresist with a processing gas at a first pressure to form a thermally dry developed patterned metal-containing photoresist, and passivating the thermally dry developed patterned metal-containing photoresist at a second pressure different from or the same as the first pressure within the same processing chamber as the thermal dry development to form a patterned substrate. In some embodiments, the first pressure is lower than the second pressure.

[0008] In some embodiments, passivating includes exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

[0009] In some embodiments, passivating includes O2, O3, CO, CO2, H2, Cx H y Flash treatment using H, H2O, H2O2, SO2, NO, NO2, N2O, NH3, or a mixture thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14.

[0010] In some embodiments, the flash treatment is carried out over a duration of from about 0.5 to about 10 seconds.

[0011] In some embodiments, the throughput of the semiconductor substrate is increased by at least about 50%.

[0012] In some embodiments, the metal-containing photoresist is an organometal comprising a photopatterned EUV-sensitive organometallic oxide, a photopatterned EUV-sensitive metal oxide, or a thin film EUV resist.

[0013] In some embodiments, the photopatterned EUV-sensitive metal oxide is tin oxide.

[0014] In some embodiments, the release of tin gas from tin oxide is mitigated.

[0015] In some embodiments, thermal dry development includes exposure to a halogen-containing gas.

[0016] In some embodiments, the method further comprises plasma dry developing the thermally dry developed patterned metal-containing photoresist, and thermal dry development, plasma dry development, and passivation are all performed within the same processing chamber.

[0017] In some embodiments, thermal dry development and plasma dry development are repeated alternately.

[0018] In some embodiments, plasma dry developing includes cyclic plasma dry developing, direct plasma dry developing, remote plasma dry developing, or continuous plasma dry developing.

[0019] In some embodiments, plasma dry developing includes continuous plasma dry developing, which is performed at variable power, constant power and pulse bias, or variable power and pulse bias.

[0020] In some embodiments, plasma dry developing includes exposing at least one halogen-containing gas in an inert carrier gas to a plasma.

[0021] In some embodiments, the halogen-containing gas is HBr, Br2, HCl, Cl2, HI, I2, or BCl3.

[0022] In some embodiments, the first pressure is about 5 mTorr to 760 Torr, and the second pressure is about 5 mTorr to 200 mTorr.

[0023] In some embodiments, the first pressure is lower than the second pressure.

[0024] In some embodiments, the method further comprises transitioning the pressure in the same processing chamber from the first pressure to the second pressure within 10 seconds, returning the pressure in the same processing chamber from the second pressure to the first pressure within 20 seconds after plasma dry developing and passivation, and maintaining one or more processing parameters uniformly.

[0025] In some embodiments, the method further comprises curing a metal-containing photoresist in the same processing chamber used for thermal dry developing.

[0026] In some embodiments, the method further comprises a step of curing the metal-containing photoresist after passivation in the same processing chamber used for thermal dry development, plasma dry development, and passivation.

[0027] In some embodiments, curing is performed by a process using a plasma of an inert gas, a process using a plasma of an oxidizing gas, a heat treatment, UV light exposure, or a combination thereof.

[0028] In a second aspect, the present disclosure includes an apparatus for performing all of the dry development and passivation of a metal-containing photoresist within a single processing chamber. In some embodiments, the apparatus includes one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to the one or more pressure regulators, a plasma processing system, one or more gas inlets to the processing chamber and associated flow control hardware, and a controller having at least one processor and a memory, the at least one processor and the memory being communicatively connected to each other, the at least one processor being at least operably connected to the associated flow control hardware, and the memory storing computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to perform thermal dry development in one of the processing chambers and perform passivation in the same processing chamber as the thermal dry development. In some embodiments, the thermal dry development is performed at a first pressure and the passivation is performed at a second pressure below the first pressure.

[0029] In some embodiments, the apparatus further comprises a photoresist thickness sensor module.

[0030] In some embodiments, the photoresist thickness sensor module is a spectral reflectometer.

[0031] In some embodiments, the apparatus further comprises computer-executable instructions for controlling at least one processor to at least control associated flow control hardware to perform plasma dry development, and all of the plasma dry development and passivation are performed within the same processing chamber.

[0032] In some embodiments, the plasma dry development includes cyclic plasma dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

[0033] In some embodiments, the plasma dry development includes continuous plasma dry development, and the continuous plasma dry development is performed at variable power, constant power and pulse bias, or variable power and pulse bias.

[0034] In some embodiments, the passivation includes exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

[0035] In some embodiments, the passivation includes a flash process using O2, O3, CO, CO2, H2, C x H y , H2O, H2O2, SO2, NO2, N2O, NH3, or a combination thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14.

[0036] In some embodiments, the first pressure is lower than the second pressure.

[0037] In some embodiments, the apparatus further comprises computer-executable instructions for controlling at least one processor to at least control associated flow control hardware to transition the pressure within the same processing chamber from the first pressure to the second pressure within 10 seconds, and to return the pressure within the same processing chamber from the second pressure to the first pressure within 20 seconds after plasma dry development and passivation, in order to maintain one or more processing parameters uniformly.

[0038] In a third aspect, the present disclosure includes an apparatus for performing all of dry development, passivation, and curing of a metal-containing photoresist within a single processing chamber. In some embodiments, the apparatus includes one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to the one or more pressure regulators, one or more gas inlets to the processing chamber and associated flow control hardware, a plasma processing system, and a controller having at least one processor and memory, where the at least one processor and memory are communicatively connected to each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to perform dry development in one of the processing chambers and passivation and curing in the same processing chamber as the dry development. In some embodiments, the dry development includes both thermal dry development and plasma dry development. In some embodiments, the dry development is performed at a first pressure and the passivation and curing are performed at a second pressure. In some embodiments, the second pressure is less than or equal to the first pressure.

[0039] In some embodiments, the apparatus further comprises a photoresist thickness sensor module.

[0040] In some embodiments, the photoresist thickness sensor module is a spectral reflectometer.

[0041] In some embodiments, curing is performed by treatment with a plasma of an inert gas, treatment with a plasma of an oxidizing gas, heat treatment, UV light exposure, or a combination thereof.

[0042] In some embodiments, passivation includes exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

[0043] In some embodiments, passivation includes flash treatment with O2, O3, CO, CO2, H2, C x H y , H2O, H2O2, SO2, NO, NO2, N2O, NH3, or a combination thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14.

[0044] In some embodiments, plasma dry development includes cyclic plasma dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

[0045] In some embodiments, plasma dry development includes continuous plasma dry development, and continuous plasma dry development is performed at variable power, at constant power and pulse bias, or at variable power and pulse bias.

[0046] In some embodiments, the apparatus further comprises a UV exposure module.

[0047] In some embodiments, the first pressure is lower than the second pressure.

[0048] In some embodiments, the apparatus further comprises computer-executable instructions for controlling at least one processor to control at least the associated flow control hardware to transition the pressure in the same processing chamber from the first pressure to the second pressure within 10 seconds, and to return the pressure in the same processing chamber from the second pressure to the first pressure within 20 seconds after plasma dry development and passivation, to maintain one or more processing parameters uniform.

[0049] In a fourth aspect, the present disclosure includes a method for performing both thermal dry development and plasma dry development within a single processing chamber. In some embodiments, the method comprises providing a metal-containing photoresist on a semiconductor substrate within the processing chamber, thermally dry developing the metal-containing photoresist within the processing chamber, and plasma dry developing the metal-containing photoresist within the processing chamber.

[0050] In some embodiments, thermally dry developing includes exposure to a first processing gas, and plasma dry developing includes exposure to a plasma of a second processing gas different from the first processing gas. In some embodiments, the first processing gas includes a halogen-containing gas, and the second processing gas includes an inert gas, a halogen-containing gas, or a combination thereof. In some embodiments, the first processing gas includes hydrogen halide.

[0051] In some embodiments, thermally dry developing is performed at a first pressure, and plasma dry developing is performed at a second pressure different from the first pressure.

[0052] In some embodiments, thermally dry developing and plasma dry developing are performed at a temperature of about -20°C to about 50°C within the processing chamber.

[0053] In some embodiments, thermally dry developing and plasma dry developing are alternately repeated.

[0054] In some embodiments, the method further comprises performing post - processing of dry development in a processing chamber. In some embodiments, the post - processing of dry development includes passivating a metal - containing photoresist within the processing chamber. Passivating may include exposure to an oxygen - containing plasma, a nitrogen - containing plasma, or a hydrogen - containing plasma. Additionally or alternatively, the post - processing of dry development may include curing the metal - containing photoresist within the processing chamber. Curing may include treatment with a plasma of an inert gas, treatment with a plasma of an oxidizing gas, heat treatment, UV light exposure, or a combination thereof.

[0055] In a fifth aspect, the present disclosure includes an apparatus for performing all of the thermal dry development and plasma dry development of a metal - containing photoresist within a single processing chamber. In some embodiments, the apparatus comprises one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to the pressure regulators, a plasma processing system, one or more gas inlets to the processing chamber and associated flow - control hardware, and a controller having at least one processor and a memory. The at least one processor and the memory are communicatively connected to each other. The at least one processor is at least operably connected to the associated flow - control hardware. The memory stores computer - executable instructions for controlling the at least one processor to at least control the associated flow - control hardware to perform thermal dry development in one of the processing chambers and plasma dry development in the same processing chamber as the thermal dry development.

[0056] These aspects and other aspects are further described below with reference to the drawings.

Brief Description of the Drawings

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[0070] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. Also, in order to avoid obscuring the disclosed embodiments needlessly, detailed descriptions of well-known processing operations are omitted. It should be understood that the disclosed embodiments are described in relation to specific embodiments, but are not intended to limit the disclosed embodiments.

[0071] Definition The term "flow control hardware" generally refers to components configured to fluidly connect one or more chemical sources to a processing chamber. Flow control hardware may include, for example, one or more mass flow controllers and / or valves. Examples of chemical sources include a dielectric film precursor source, a halogen-containing precursor source, a reactive gas source, and an inert gas source.

[0072] The term "formation of a mixed gas" generally means either or both of mixing a plurality of gases before introducing them into a processing chamber or mixing a plurality of gases within the processing chamber.

[0073] The term "inert gas" generally refers to a gaseous material that does not react with other chemicals within a processing chamber during substrate processing. Examples of inert gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), and xenon (Xe), as well as nitrogen (N2) in some processes.

[0074] The term "plasma" generally means a gas containing cations, free radicals, and free electrons. The term "in-situ plasma" generally means a plasma formed at a processing station within a processing chamber. The term "remote plasma" generally means a plasma formed at a location remote from a processing station within a processing chamber.

[0075] The term "plasma generator" generally means a combination of components that can be utilized to form a plasma. Examples of components include a high-frequency power source, an impedance matching circuit network, and one or more electrodes.

[0076] The term "precursor" generally means a chemical species that adsorbs onto a substrate surface in an ALD process. The precursor reacts with a reactant to convert the adsorbed precursor into a film layer.

[0077] The term "processing chamber" or "process chamber" generally means a container in which chemical and / or physical processing is performed on a substrate. The pressure, substrate temperature, and ambient composition within the processing chamber can be controllable to perform chemical and / or physical processing.

[0078] The term "processing tool" generally means a machine comprising a processing chamber and hardware configured to enable processing to be performed within the processing chamber.

[0079] The term "processing station" generally means a location within a processing chamber where a substrate is placed during processing.

[0080] The term "reactant" means a chemical species that reacts with a precursor adsorbed on a substrate surface during an ALD process to form a film layer. The reaction between the reactant and the precursor can be promoted by thermal energy and / or plasma in various processes.

[0081] As used herein, the term "semiconductor substrate" refers to a substrate at any stage of semiconductor device manufacturing that includes a semiconductor material anywhere within its structure. It is understood that the semiconductor material within the semiconductor substrate need not be exposed. A semiconductor wafer having multiple layers of other materials (e.g., dielectrics) covering the semiconductor material is an example of a semiconductor substrate. In the following detailed description, it is assumed that the disclosed embodiments are implemented on a semiconductor wafer (such as a 200 mm, 3 mm, or 450 mm semiconductor wafer). However, the disclosed embodiments are not limited thereto. The workpiece may have various shapes, sizes, and materials. In addition to semiconductor wafers, other workpieces that can utilize the disclosed embodiments include various articles such as printed circuit boards.

[0082] The embodiments disclosed below describe the deposition of materials onto a substrate (such as a wafer, substrate, or other workpiece). The workpiece may have various shapes, sizes, and materials. In this application, the terms "semiconductor wafer", "wafer", "substrate", "wafer substrate", and "integrated circuit in process" are used interchangeably. One of ordinary skill in the art will understand that the term "integrated circuit in process" can refer to a silicon wafer at any stage during the many stages of integrated circuit manufacturing. Wafers or substrates used in the semiconductor device industry typically have a diameter of 200 mm, 300 mm, or 450 mm. Unless otherwise specified, the details of the processes described herein (e.g., flow rates, power levels, etc.) are suitable for processing a 300 mm diameter substrate or for handling a chamber configured to process a 300 mm diameter substrate, and may be scaled up or down to be suitable for other sized substrates or chambers. In addition to semiconductor wafers, other workpieces that can be used in conjunction with the embodiments disclosed herein include various articles such as printed circuit boards. The processes and apparatus can be used in the manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, etc.

[0083] As used herein, the term "photoresist" and its derivatives refer to a photosensitive material used in processes (such as photolithography, photoetching, or photoengraving) for forming a patterned coating on a surface. A photoresist material changes its solubility in a developer when exposed to light of a specific wavelength. The photoresist layer can be composed of a positive-type (the exposed area becomes soluble) or negative-type (the exposed area becomes insoluble) photoresist material.

[0084] For the purposes of the present disclosure, it should be understood that "metal" as used in this context means a conductor having a maximum resistivity of 500 microohm-cm, such as metals and conductive metal salts (in particular, conductive metal nitrides, e.g., TiN).

[0085] As used herein, "metal-containing photoresist" includes, but is not limited to, metal photoresists, semimetal photoresists, metal oxide photoresists, or organometallic oxide photoresists.

[0086] "Tin oxide" as used herein is considered to include everything stoichiometrically possible for Sn x O y For example, "tin oxide" includes compounds having the chemical formula SnO n where 1 ≤ n ≤ 2 and n can be an integer or non-integer value. "Tin oxide" can include metastoichiometric compounds (such as SnO 1.8 ). "Tin oxide" also includes tin dioxide (SnO2 or stannic oxide) and tin monoxide (SnO or stannous oxide). "Tin oxide" includes both natural and synthetic variations and all crystal and molecular structures. "Tin oxide" also includes amorphous tin oxide.

[0087] As used herein, the expression "at least one of A, B, and C" should be construed to mean the logic (A or B or C) using the non-exclusive logical "or", and should not be construed to mean "at least one of A, at least one of B, and at least one of C".

[0088] As used herein, the term "about" is understood to account for being slightly greater and / or less than the recited value, and the variations do not significantly affect the desired function of the parameter outside the recited value. In some cases, "about" includes + / - 10% of any recited value. As used herein, this term modifies any recited value, range of values, or endpoints of one or more ranges.

[0089] As used herein, the terms "top", "bottom", "upper", "lower", "above", and "below" are used to indicate the relative relationship between structures. The use of these terms does not imply or require that a particular structure must be located in a particular position of the device.

[0090] Introduction and Context The present disclosure generally relates to the field of semiconductor processing. In particular, the present disclosure is directed to the development of photoresists such as metal-containing photoresists. Such metal-containing photoresists and / or metal-oxide-containing photoresists can undergo one or both of thermal dry development and / or plasma dry development. Such metal-containing photoresists and / or metal-oxide-containing photoresists can undergo a process to change the chemical, physical, and / or optical properties of the photoresist after development and before pattern transfer. The processing of the photoresist improves the performance of the photoresist. For example, photoresist processing can reduce the dose-to-size (DtS), reduce the LWR, increase the line CD, improve the etch resistance, increase the throughput, reduce the gas evolution of tin or other elements, and / or reduce the defects / opens. The throughput can be increased by at least about 40%, 50%, about 60%, about 70%, about 80%, or about 90%.

[0091] The patterning of thin films in semiconductor processing is often an important step in semiconductor manufacturing. Patterning includes lithography. In conventional photolithography (such as 193 nm photolithography), by exposing a photoresist to photons in a selective area defined by a photomask, a chemical reaction is caused in the exposed photoresist, and a chemical contrast that can be utilized in the development process to remove specific portions of the photoresist to form a pattern is created, whereby the pattern is printed on the photosensitive photoresist film. The patterned and developed photoresist film can then be used as an etching mask for transferring the pattern to an underlying film composed of metal, oxide, etc.

[0092] (As defined by the International Technology Roadmap for Semiconductors) Advanced technology nodes include 22 nm, 16 nm, and nodes beyond. For example, at the 16 nm node, the width of vias or lines in a damascene structure is typically about 30 nm or less. Feature scaling in advanced semiconductor integrated circuits (ICs) and other devices has driven the improvement of lithography resolution.

[0093] Extreme ultraviolet (EUV) lithography can extend lithography technology by moving to shorter imaging source wavelengths than achievable with conventional photolithography methods. EUV light sources with wavelengths of about 10 - 20 nm or 11 - 14 nm (e.g., a wavelength of 13.5 nm) can be utilized in state-of-the-art lithography tools (also called scanners). Since EUV radiation is strongly absorbed by a wide range of solid and fluid materials including quartz and water vapor, it is applied in a vacuum.

[0094] EUV lithography utilizes a patterned EUV resist to form a mask for use in etching underlying layers. The EUV resist may be a polymer-based chemically amplified resist (CAR) generated by liquid-based spin-on technology. Alternatives to CAR are metal oxide-containing films (such as those made by Inpria of Corvallis, Oregon) that can be directly photopatterned and are described, for example, in U.S. Patent Publications Nos. US2017 / 0102612, US2016 / 0216606, and US2016 / 0116839, which are incorporated herein by reference for their disclosures regarding at least photopatternable metal oxide-containing films. Such films may be formed by spin-on technology or by dry deposition. The metal oxide-containing films can be directly (i.e., without using a separate photoresist) patterned by EUV exposure in a vacuum atmosphere, as described, for example, in U.S. Patent No. 9,996,004, "EUV PHOTOPATTERNING OF VAPOR-DEPOSITED METAL OXIDE-CONTAINING HARDMASKS," issued June 12, 2018, and / or International Application No. PCT / US19 / 31618, "METHODS FOR MAKING EUV PATTERNABLE HARD MASKS," filed May 9, 2019, and published as International Publication No. WO2019 / 217749, to provide a patterning resolution of less than 30 nm, and their disclosures regarding at least the composition, deposition, and patterning of directly photopatternable metal oxide films for forming EUV resist masks are incorporated herein by reference. Generally, patterning includes exposing the EUV resist with EUV radiation to form a photopattern in the resist and then developing to remove a portion of the resist according to the photopattern to form a mask.

[0095] A direct photo-patternable EUV or DUV resist may be composed of, or may include, metals and / or metal oxides mixed within an organic component. The metal / metal oxide may promote EUV or DUV photon adsorption, generate secondary electrons, and / or exhibit a high etching selectivity with respect to the underlying film stack and device layers. These resists are developable using a wet (solvent) approach, in which the wafer needs to be transferred to a track where the wafer is exposed to a developing solvent, dried, and then baked. Such resists may also be developed using a dry approach or a combination of wet and dry approaches, as described herein.

[0096] Generally, a resist can be utilized as a positive-tone resist or a negative-tone resist by controlling the chemical nature of the resist and / or the solubility or reactivity of the developer. It is beneficial to have an EUV or DUV resist that can function as either a negative-tone resist or a positive-tone resist.

[0097] The following describes techniques related to EUV processing, although such techniques may also be applicable to other next-generation lithography techniques. Various radiation sources may be used, such as EUV (generally about 13.5 nm), DUV (deep UV, generally in the range of 248 nm or 193 nm with an excimer laser source), X-rays (including EUV in the low-energy range of the X-ray region), and e-beam (including a wide energy range).

[0098] FIG. 1 is a flowchart showing the steps of a conventional method for depositing, developing, and processing a photoresist. The patterning process flow often refers to the EUV photosensitive resist in FIG. 1, but it is understood that the process flow is not limited to EUV resist. An EUV resist may be a resist that is sensitive to EUV radiation. The operations of process 100 may be performed in a different order and / or may be performed with different, fewer, or additional operations. In some embodiments, the operations of process 100 may be performed at least in part in accordance with software stored on one or more non-transitory computer-readable media.

[0099] In block 102 of process 100, a layer of photoresist is deposited. This may be either a dry deposition process (such as a vapor deposition process) or a wet deposition process (such as a spin-on deposition process). In one embodiment, a metal-containing precursor is deposited as a solution using a liquid-based spin-on technique. In another embodiment, the metal-containing precursor is deposited in the form of a vapor using a dry technique (e.g., chemical vapor deposition).

[0100] A photoresist film can be deposited on a substrate. Such a film can be deposited using a wet or dry deposition process in which a metal-containing precursor (e.g., any precursor described herein, such as a tin-containing precursor) is provided near the substrate. In one embodiment, the metal-containing precursor is deposited as a solution using a liquid-based spin-on technique. In another embodiment, the metal-containing precursor is deposited in the form of a vapor using a dry technique (e.g., chemical vapor deposition). Although the present disclosure often shows the metal-containing precursor as a tin-containing precursor, other metal atoms may be used.

[0101] The layers and films described herein are 1×10 7 cm 2It may contain an element (e.g., a metal atom or a non-metal atom) having a high photoabsorption cross-section such as below / mol. Such an element can be provided by depositing one or more precursors to provide an imaging layer.

[0102] In some embodiments, the film is a radiation-sensitive film (e.g., an EUV-sensitive film). This film can then function as an EUV resist, as further described herein. In certain embodiments, the layer or film may contain one or more ligands (e.g., ligands unstable to EUV) that can be removed, cleaved, or cross-linked by radiation (e.g., EUV or DUV radiation).

[0103] The precursor can provide a radiation-sensitive patterning-capable film (or a patterning radiation-sensitive film or a photopatterning-capable film). Such radiation can include EUV radiation, DUV radiation, or UV radiation that becomes patterned radiation when supplied by irradiation through a patterned mask. The film itself can be modified by exposure to such radiation such that the film becomes radiation-sensitive or sensitive. In certain embodiments, the precursor is an organometallic compound and contains at least one metal center.

[0104] The precursor may have any useful number and type of ligands. In some embodiments, the ligands can be characterized by being able to react in the presence of a counter-reactant or in the presence of patterned radiation. For example, the precursor may contain a ligand that reacts with a counter-reactant, thereby introducing a bond (e.g., an -O- bond) between metal centers. In another example, the precursor may contain a ligand that desorbs in the presence of patterned radiation.

[0105] The precursor has a high patterning radiation absorption cross-section (e.g., 1x10 7 cm 2It may contain a metal or a semimetal or an atom having an EUV absorption cross section of 0 or more / mol. In some embodiments, M is tin (Sn), bismuth (Bi), tellurium (Te), cesium (Cs), antimony (Sb), indium (In), molybdenum (Mo), hafnium (Hf), iodine (I), zirconium (Zr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), silver (Ag), platinum (Pt), and lead (Pb).

[0106] In certain embodiments, the precursor comprises tin. Non-limiting tin precursors include SnF2, SnH4, SnBr4, SnCl4, SnI4, tetramethyltin (SnMe4), tetraethyltin (SnEt4), trimethyltin chloride (SnMe3Cl), dimethyltin dichloride (SnMe2Cl2), methyltin trichloride (SnMeCl3), tetraallyltin, tetravinyltin, hexaphenylditin(IV) (Ph3Sn-SnPh3, where Ph is phenyl), dibutyldiphenyltin (SnBu2Ph2), trimethyl(phenyl)tin (SnMe3Ph), trimethyl(phenylethynyl)tin, tricyclohexyltin hydride, tributyltin hydride (SnBu3H), dibutyltin diacetate (SnBu2(CH3COO)2), tin(II) acetylacetonate (Sn(acac)2), tributyltin ethoxide (SnBu3(OEt)), dibutyltin dimethoxide (SnBu2(OMe)2), tributyltin methoxide (SnBu3(OMe)), tin(IV) tert-butoxide (Sn(t-BuO)4), n-butyltin tributoxide (Sn(n-Bu)(t-BuO)3), tetrakis(dimethylamino)tin (Sn(NMe2)4), tetrakis(ethylmethylamino)tin (Sn(NMeEt)4), tetrakis(diethylamino)tin(IV) (Sn(NEt2)4), (dimethylamino)trimethyltin(IV) (Sn(Me)3(NMe2), Sn(i-Pr)(NMe2)3, Sn(n-Bu)(NMe2)3, Sn(s-Bu)(NMe2)3, Sn(i-Bu)(NMe2)3, Sn(t-Bu)(NMe2)3, Sn(t-Bu)2(NMe2)2, Sn(t-Bu)(NEt2)3, Sn(tbba), Sn(II)(1,3-bis(1,1-dimethylethyl)-4,5-dimethyl-(4R,5R)-1,3,2-diazastannolidine-2-ylidene), or bis[bis(trimethylsilyl)amino]tin (Sn[N(SiMe3)2]2).

[0107] Examples of deposition techniques (e.g., for a film) include ALD (e.g., thermal ALD and plasma-enhanced ALD), spin-coat deposition, PVD such as PVD co-sputtering, CVD (e.g., PE-CVD or LP-CVD), sputter deposition, electron beam deposition including electron beam co-evaporation, or combinations thereof (such as combinations of ALD and CVD components, processes such as discontinuous ALD where precursors and counter-reactants are separated in time or space), etc., including any of the techniques described herein.

[0108] Further description of precursors applicable to the present disclosure and methods for depositing them as EUV photoresist films can be found in International Application No. PCT / US19 / 31618, "METHODS FOR MAKING EUV PATTERNABLE HARD MASKS", filed on May 9, 2019 and published as International Publication No. WO2019 / 217749. The thin film may include optional materials in addition to the precursors and counter-reactants to change the chemical or physical properties of the film, such as for the purpose of changing the sensitivity of the film to EUV or enhancing the etching resistance. Such optional materials may be introduced, for example, by doping during gas phase formation before, during, and / or after deposition onto the substrate. In some embodiments, a gentle remote H2 plasma may be introduced, for example, to replace some Sn-L bonds with Sn-H, thereby increasing the reactivity of the resist under EUV. In other embodiments, CO2 may be introduced to replace some Sn-O bonds with Sn-CO3 bonds, and the latter bonds may have higher resistance to wet development.

[0109] The various atoms present in the precursors and / or counter-reactants can be provided within a capping layer, which is then disposed on any beneficial layer or structure. The capping layer can have any beneficial thickness (e.g., from about 0.1 nm to about 5 nm, any of the thicknesses described herein).

[0110] Furthermore, two or more different precursors may be utilized within each layer (e.g., film or capping layer). For example, two or more of any of the metal-containing precursors herein may be utilized to form an alloy. Further examples of EUV photosensitive materials as well as processing methods and apparatuses are described in U.S. Patent No. 9,996,004, International Patent Publication No. WO2020 / 102085, and International Patent Publication No. WO2019 / 217749, each of which is hereby incorporated by reference in its entirety.

[0111] In some embodiments, the photoresist film may be deposited on the underlying layer. In some embodiments, the underlying layer may be deposited on a hard mask such as an ashingable hard mark (AHM). The underlying layer is configured to enhance adhesion between the subsequently formed EUV resist and the substrate. Also, the underlying layer is configured to reduce the EUV dose for effective EUV exposure of the EUV resist. The underlying layer may include a deposited film of a hydrocarbon doped with a non-carbon heteroatom (such as oxygen (O), silicon (Si), nitrogen (N), tungsten (W), boron (B), iodine (I), chlorine (Cl), or a combination thereof). For example, an underlying layer including a hydrocarbon film doped with iodine may improve the generation of secondary electrons in the EUV resist upon exposure to EUV radiation. The underlying layer may have a thickness of about 25 nm or less (e.g., between about 2 nm and about 20 nm). In some examples, the underlying layer may be deposited using a deposition technique (such as PECVD or ALD).

[0112] In block 104 of process 100, the backside or bevel of the substrate may optionally be cleaned and / or the edge bead of the photoresist deposited in a previous step may be removed. Such cleaning or removal steps may be useful for removing particles that may be present after the photoresist layer is deposited. The removal step may include processing the wafer in a wet metal oxide (MeOx) edge bead removal (EBR) process.

[0113] In block 106 of process 100, post-application bake (PAB) or post-application treatment can be optionally performed. Such treatment can improve the etching resistance of unexposed material to aqueous or non-aqueous solutions. In one example, such treatment can enhance the chemical composition difference (or contrast) between the unexposed region and the exposed region, and thus the PAB operation is performed. In another example, such treatment can reduce the chemical composition difference (or contrast) between the unexposed region and the exposed region, and thus the PAB operation is not performed. In yet another example, the use of PAB removes residual moisture from the film to form a cured resist film. PAB may include a combination of heat treatment, chemical exposure, and / or wetting to increase the EUV sensitivity of the film, thereby reducing the EUV dose required to develop a pattern in the film. In certain embodiments, the PAB process is performed at a temperature higher than about 100 °C, or at a temperature of about 100 °C to about 200 °C, or at about 100 °C to about 250 °C. In other embodiments, the PAB process is performed at a temperature of about 190 °C to about 350 °C in the absence of an O-containing gas. In another example, the post-application treatment includes exposing the film to an inert gas or CO2, which may optionally include cooling or heating. The use of an inert gas can provide metal-oxygen-metal species, and the use of CO2 can provide metal carbonate species in the film.

[0114] In block 108 of process 100, the film is exposed to EUV radiation to develop the pattern. Generally, EUV exposure can create a contrast in the etching selectivity that can be utilized to change the chemical composition of the film and remove a portion of the film. Such contrast can provide a positive tone resist. However, it is understood that EUV exposure can instead cause a contrast such that the unexposed regions (or less exposed regions) are selectively removed. Such contrast can provide a negative tone resist as described herein. The more exposed areas of the photoresist with changed physical or chemical properties relative to the less exposed areas are generated through photopatterning. The difference in properties between the more exposed areas and the less exposed areas can be utilized in subsequent processing. EUV exposure can include, for example, exposure having a wavelength in the range of about 10 nm to about 20 nm (e.g., about 13.5 nm) in a vacuum atmosphere.

[0115] In block 110 of process 100, post-exposure bake (PEB) is performed on the exposed film, thereby further removing residual moisture, promoting chemical concentration in the film, or enhancing the contrast in the etching selectivity of the exposed film, or post-treating the film in any useful way. In one example, such treatment can reduce the difference (or contrast) in chemical composition between the unexposed and exposed regions, and thus the PEB operation is not performed. In another example, the exposed film may be heat-treated (e.g., at a low temperature and / or optionally in the presence of various chemical species) to promote reactivity within the EUV-exposed or unexposed portions of the resist upon exposure to a stripping agent or a positive tone developer (e.g., a halogen compound-based aqueous acid such as HCl, HBr, HI, or a combination thereof). In another example, the exposed film may be heat-treated (e.g., at a low temperature) to further crosslink ligands within the EUV-unexposed portion of the resist, thereby providing an EUV-exposed portion that can be selectively removed upon exposure to a stripping agent (e.g., a positive tone developer). In yet another example, PEB is omitted.

[0116] In block 112 of process 100, the photoresist pattern is developed by positive tone development or negative tone development. In various embodiments of development, the unexposed regions are selectively removed (to provide a pattern within a negative tone resist). These steps may be wet processed using one or more developers or developer solutions, followed by an optional rinse operation (using, for example, deionized water or another solvent) or an optional drying operation (using air or under inert conditions, for example, with optional heat). In certain embodiments, the development process is a wet process. In other embodiments, the development process is a dry process. For example, dry processing includes a halide-containing chemical substance.

[0117] Dry development processing may include thermal (without plasma) dry development processing, plasma dry development processing, or a combination of thermal dry development processing and plasma dry development processing. In some embodiments, the dry development gas may include a halide-containing chemical substance (such as hydrogen halide). Thus, the developer may include hydrogen halide (e.g., HBr, HCl, etc.), hydrogen and halogen gases (e.g., H2 and Cl2, H2 and Br2, etc.), boron trichloride, organic halides, acyl halides, carbonyl halides, thionyl halides, or mixtures thereof. Organic halides are C x H y F z 、C x H y Cl z 、C x H y Br z 、および、C x H y I z(Here, x, y, and z may include, but are not limited to, values of 0 or greater. The acyl halide may include, but is not limited to, CH3COF, CH3COCl, CH3COBr, and CH3COI. The carbonyl halide may include, but is not limited to, COF2, COCl2, COBr2, and COI2. The thionyl halide may include, but is not limited to, SOF2, SOCl2, SoBr2, and SOI2. In some embodiments, the dry development gas may be flowed with or without an inert / carrier gas such as He, Ne, Ar, Xe, and N2. In some embodiments, the dry development may include a heat treatment, a plasma treatment, or a combination of a heat treatment and a plasma treatment. Parameters such as chamber pressure, gas flow rate, substrate temperature, and exposure time may be adjusted. In some embodiments, the chamber pressure may be between about 5 mTorr and about 760 Torr. In some embodiments, the substrate temperature may be between about -60 °C and about 300 °C. In some embodiments where plasma is applied, the RF level may be adjusted to an RF power level of about 1000 W or less. Selecting a development method along with optimizing the development parameters can affect the selectivity, roughness, descumming, and other characteristics of the development.)

[0118] After block 112, post-development inspection may be performed. If necessary, rework is performed by returning and repeating step 102.)

[0119] In block 114 of process 100, the photoresist is processed before pattern transfer. The processing may be a heat treatment, a plasma treatment, a chemical treatment, a selective deposition treatment, or a combination of these treatments. The heat treatment may expose the photoresist to a high temperature between about 200 °C and about 300 °C to reduce defects and LWR. The plasma treatment may expose the photoresist to a plasma such as a direct (in-situ) plasma or a remote plasma to increase the density of the photoresist and reduce LWR. In some embodiments, the plasma treatment may include passivation. Passivation may include a flash treatment involving exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. In some embodiments, the plasma treatment may include curing. Curing may include exposure to a plasma of an inert gas and / or exposure to UV light. The chemical treatment may expose the photoresist to reactive species such as a halogen compound-based species (e.g., tungsten hexafluoride) or a carbon-containing precursor (e.g., carbon monoxide, an organometallic precursor) to increase etch resistance, reduce gas evolution, and increase line CD. The selective deposition treatment may expose the photoresist to a chemical precursor for selectively depositing a protective coating on the photoresist to reduce DtS, improve etch resistance, reduce gas evolution, and increase line CD. Any one or more of the above-described treatments is applied to the photoresist after development to improve the performance of the photoresist during pattern transfer.

[0120] In block 116 of process 100, one or more substrate layers are etched using a photoresist mask for pattern transfer. Such substrate layers are beneath the photoresist mask and may be removable by lithographic etching. The pattern transfer etching may etch the material to a desired depth to form a plurality of patterned features. In some embodiments, one or more substrate layers are amorphous carbon (a-C), amorphous silicon (a-Si), tin oxide (e.g., S n O x) Silicon oxide (e.g., SiO2), silicon oxynitride (e.g., SiO x N y ), silicon oxycarbide (e.g., SiO x C y ), silicon nitride (e.g., Si3N4), titanium oxide (e.g., TiO2), titanium nitride (e.g., TiN), tungsten (e.g., W), doped carbon (e.g., W-doped C), tungsten oxide (e.g., WO x ), hafnium oxide (e.g., HfO2), zirconium oxide (e.g., ZrO2), and aluminum oxide (e.g., Al2O3) may be included. Any defects or CD variations in the photoresist mask are reproduced in the material being patterned during pattern transfer etching. Further, if the etching resistance is poor, it has an adverse effect on the transfer of the pattern to the underlying substrate layer during etching. The post-development processing of the photoresist mask alleviates the above problems and ensures the success of pattern transfer during pattern transfer etching.

[0121] After pattern transfer, post-etch inspection may be performed. If necessary, rework is performed by repeating step 102.

[0122] Figures 2A - 2C are schematic cross-sectional views providing an overview of various processing steps including the development and processing of the photoresist. As shown in Figure 2A, the wafer 200 comprises a substrate 202 and a substrate layer 204 to be etched. The patterning structure may include any useful substrate. For example, the input wafer may be prepared to have a substrate surface of the desired material, and the topmost material is the layer onto which the resist pattern is transferred. The material selection may vary depending on the integration, but generally, it is desirable to select a material that can be etched with a high selectivity (i.e., much faster) with respect to the EUV resist or imaging layer.

[0123] In some embodiments, the substrate is a hard mask, and the hard mask is used in the lithography etching of the underlying semiconductor material. The hard mask is amorphous carbon (a-C), tin oxide (e.g., SnOx ) Silicon oxide (e.g., SiO such as SiO2 x ) Silicon oxynitride (e.g., SiO x N y ) Silicon oxycarbide (e.g., SiO x C y ) Silicon nitride (e.g., Si3N4), titanium oxide (e.g., TiO2), titanium nitride (e.g., TiN), tungsten (e.g., W), doped carbon (e.g., W-doped C), tungsten oxide (e.g., WO x ), hafnium oxide (e.g., HfO2), zirconium oxide (e.g., ZrO2), and aluminum oxide (e.g., Al2O3), etc., may include any of various materials. Suitable substrate materials include various carbon-based films (e.g., an ashing hard mask (AHM)), silicon-based films (e.g., SiO x , SiC x , SiO x C y , SiO x N y , SiO x C y N z ), a-Si:H, poly-Si, or SiN), or may include any other film (generally, a sacrificial film) applied to facilitate patterning. For example, the substrate may preferably include SnO x (such as SnO2). In various embodiments, the layer may have a thickness of 1 nm to 100 nm, or a thickness of 2 nm to 10 nm.

[0124] In some embodiments, the substrate layer 204 comprises an etchable hard mask such as amorphous carbon, spin-on carbon, or other materials (e.g., silicon, silicon oxide, silicon nitride, silicon carbide, etc.). In some embodiments, the substrate layer 204 may be a layer stack disposed on the substrate 202. The wafer 200 further comprises a photopatterned metal-containing EUV resist film 206. For example, the photopatterned metal-containing EUV resist film 206 may be an organometal-containing layer disposed on the substrate layer 204 to be etched. The photopatterned metal-containing EUV resist film 206 may have a thickness between about 5 nm and about 50 nm or between about 10 nm and about 30 nm. The photopatterned metal-containing EUV resist film 206 may be provided in a processing chamber after photopatterning in an EUV scanner and / or after PEB treatment. The photopatterned metal-containing EUV resist film 306 includes a non-EUV exposure region 206a and an EUV exposure region 206b.

[0125] As shown in FIG. 2B, the non-EUV exposure region 206a of the photopatterned metal-containing EUV resist film 206 is removed by a development process. The development may use a wet developer or a dry developer. When a dry developer is utilized, the dry development may proceed with or without plasma ignition. In some examples, the dry developer may include a halide-containing chemical. The photoresist mask of the photopatterned metal-containing EUV resist film 206 is formed by the removal of the non-EUV exposure region 206a after development. FIGS. 2A-2C illustrate negative tone development, but it is understood that positive tone development may alternatively be applied in the present disclosure.

[0126] As shown in FIG. 2C, the substrate layer 204 is etched using a photoresist mask 208 to form a recess feature defined by the photoresist mask 208 within the wafer 200. The wafer 200 undergoes pattern transfer etching such that the etchant selectively removes the substrate layer 204 relative to the chemically modified photoresist mask 208. The pattern transfer etching may be performed by dry etching or wet etching. For example, the dry etching may utilize a fluorine-based plasma etching process or an oxygen-based plasma etching process. The pattern transfer etching may etch through the substrate layer 204 according to the pattern defined by the photoresist mask 208. In some embodiments, the photoresist mask 208 maintains or at least substantially maintains an increased line CD after the pattern transfer etching.

[0127] Returning to FIG. 1, the various steps of process 100 were conventionally performed in separate chambers, involving transferring the wafer from one processing chamber to the next for the next operation. For example, steps of process 100, such as those represented by block 112 for development and block 114 for post-development processing, were conventionally performed in separate chambers. Dry development may be performed in a dry development chamber (e.g., a thermal dry development chamber). Post-development processing (post-development bake) may be performed in a bake chamber. Optionally, subsequent post-development processing (line hardening) may be performed in a UV chamber. This can lead to a longer queue time between dry development and dry post-development processing. In some examples, this can potentially cause contamination to the backside of the wafer due to gas emission. To improve the efficiency and throughput of the process and to limit potential sources of contamination, the number of steps and / or chambers for the various operations can be reduced by the methods disclosed herein.

[0128] In particular, the efficiency of the conventional process 100 as shown in FIG. 1 can be improved by performing the steps represented by block 112 together with post-development processing within the same processing chamber in a manner that eliminates the need for a separate chamber. Specifically, the efficiency of the process 100 as shown in FIG. 1 can be improved by performing development together with passivation or passivation and curing within the same processing chamber in a manner that eliminates the need for a separate post-development bake within a separate chamber.

[0129] The present disclosure relates to all-in-one dry development of photoresist. The dry development process may be performed in the same processing chamber. The dry development process and the post-dry development process may be performed in the same processing chamber. A metal-containing photoresist or a metal-oxide-containing photoresist may be deposited by wet deposition or dry deposition. The metal-containing photoresist or the metal-oxide-containing photoresist has a high absorption of EUV radiation such that the photoresist can be patterned by EUV exposure to form exposed and unexposed regions. After dry development selectively removes the exposed or unexposed regions of the photopatterned metal-containing photoresist or metal-oxide-containing photoresist, the developed photoresist may be processed. Such processing may include one or more of the following operations: (i) thermal annealing, (ii) plasma exposure, (iii) reactive gas exposure, and (iv) selective deposition of a protective layer. Such processing may achieve one or more of the following advantages: reduction of defects, reduction of LWR, reduction of DtS, reduction of gas evolution (e.g., gas evolution of tin), improvement of etching resistance, and increase of line CD, thereby improving the performance of the metal-containing photoresist or metal-oxide-containing photoresist during etching.

[0130] In this specification, specific embodiments of the present disclosure are referred to in detail. Examples of specific embodiments are illustrated in the accompanying drawings. Although the present disclosure is described in relation to these specific embodiments, it should be understood that there is no intention to limit the present disclosure to such specific embodiments. On the contrary, it is intended to cover alternatives, modifications, and equivalents that may be included within the spirit and scope of the present disclosure. In the following description, numerous specific details are set forth in order to facilitate a complete understanding of the present disclosure. The present disclosure may be practiced without some or all of these specific details. Also, in order to avoid obscuring the present disclosure unnecessarily, detailed descriptions of well-known processing operations are omitted.

[0131] As described above, the present disclosure provides a method for a film on a semiconductor substrate that can be patterned using EUV or other next-generation lithography techniques. The method includes a method in which a polymerized organometallic material is generated in a vapor and deposited on the substrate. In some embodiments, dry deposition can utilize any useful precursor (e.g., metal halides, capping agents, or organometallic agents described herein). In other embodiments, a spin-on formulation may be used. The deposition process may include applying an EUV-sensitive material as a resist film or an EUV-sensitive film.

[0132] Such an EUV-sensitive film includes a material that undergoes changes such as the loss of bulky pendant ligands bonded to metal atoms upon exposure to EUV. If the unexposed regions contain a high-density M-O-M-rich material, the cleavage due to EUV can provide an intermediate that is more easily removed by a positive-tone developer.

[0133] By EUV patterning, an area of a film is formed in which physical or chemical properties are changed as compared with non-exposed areas. These properties can be utilized in subsequent processes, such as for dissolving either the non-exposed area or the exposed area, or for selectively depositing a material on either the exposed area or the non-exposed area. In some embodiments, the unexposed film has a hydrophobic surface, and the exposed film has a hydrophilic surface under the conditions under which such subsequent processes are performed (it is recognized that the hydrophilicity of the exposed and non-exposed areas is relative to each other). For example, the removal of the material may be performed by utilizing differences in the chemical composition, density, and cross-linking of the film. The removal may be removal by wet processing or dry processing, as further described herein.

[0134] The thickness of the EUV-patternable film formed on the surface of the substrate can vary according to the surface features, the materials being used, and the processing conditions. In various embodiments, the film thickness can range from about 0.5 nm to about 100 nm. The film preferably has a thickness sufficient to absorb most of the EUV light under the conditions of EUV patterning. For example, the total absorption rate of the resist film may be 30% or less (e.g., 10% or less or 5% or less) so that the resist material at the bottom of the resist film is sufficiently exposed. In some embodiments, the film thickness is from 10 nm to 20 nm. Without limiting the mechanism, function, or usefulness of the present disclosure, the processes of the present disclosure are considered applicable to various substrates. Further, as described above, since the deposited film can closely conform to the surface features, it provides an advantage when forming a mask on a substrate (such as a substrate having features thereunder) without "filling" such features or otherwise planarizing them.

[0135] The film may be composed of a metal oxide layer deposited in any useful manner. Such a metal oxide layer, in combination with a reactant, may be deposited or coated by using any EUV photosensitive material described herein, such as a precursor (e.g., a metal-containing precursor, a metal halide, a capping agent, or an organometallic agent). In an exemplary process, a polymerized organometallic material is formed in situ in the gas phase or on the surface of a substrate to provide the metal oxide layer. The metal oxide layer may be used as a film, an adhesion layer, or a capping layer.

[0136] Generally, the method may include mixing a vapor stream of a precursor (e.g., a metal-containing precursor such as an organometallic agent) with a vapor stream of an optional reactant to form a polymerized organometallic material, and depositing the organometallic material on the surface of a semiconductor substrate. In some embodiments, a polymerized organometallic material can be formed by mixing the precursor and the optional reactant. As will be understood by those skilled in the art, the mixing and deposition aspects of the process may be carried out in parallel in a substantially continuous process.

[0137] In an example of a continuous CVD process, two or more gas streams from sources of the precursor and the optional reactant are introduced into the deposition chamber of a CVD apparatus through separate inlets, where the gases are mixed and reacted in the gas phase to form an aggregated polymer material or film (e.g., by formation of metal-oxygen-metal bonds) on the substrate. The gas streams may be introduced, for example, using separate inlets or a dual-plenum showerhead. The apparatus is configured such that the flows of the precursor and the optional reactant are mixed within the chamber, enabling the precursor and the optional reactant to react to form a polymerized organometallic material or film (e.g., a metal oxide coating or an aggregated polymer material, such as by formation of metal-oxygen-metal bonds).

[0138] To deposit a metal oxide, the CVD process is generally carried out under reduced pressure such as 0.1 Torr to 10 Torr. In some embodiments, the process is carried out at a pressure of 1 Torr to 2 Torr. The temperature of the substrate is preferably lower than the temperature of the reaction gas stream. For example, the substrate temperature may be from 0 °C to 250 °C, or from ambient temperature (e.g., 23 °C) to 150 °C.

[0139] To deposit an aggregated polymer material, the CVD process is generally carried out under reduced pressure such as 10 mTorr to 10 Torr. In some embodiments, the process is carried out at 0.5 to 2 Torr. The temperature of the substrate is preferably below the temperature of the reaction gas stream. For example, the substrate temperature may be from 0 °C to 250 °C, or from ambient temperature (e.g., 23 °C) to 150 °C. In various processes, the deposition of the polymerized organometallic material onto the substrate occurs at a rate inversely proportional to the surface temperature. Without limiting the mechanism, function, or utility of the present disclosure, it is believed that the product of such a gas-phase reaction has a larger molecular weight because the metal atoms are cross-linked by the counter-reactant and then condensed or otherwise deposited onto the substrate. In various embodiments, the steric hindrance of the bulky alkyl groups further inhibits the formation of a densely packed network and produces a highly porous low-density film.

[0140] A potential advantage of using a dry deposition method is that it is easy to adjust the composition of the film as the film grows. In a CVD process, this may be achieved by varying the relative flow rates of the first precursor and the second precursor during deposition. Deposition can occur at a temperature of 30 °C to 200 °C and a pressure of 0.01 Torr to 100 Torr (more typically about 0.1 Torr to 10 Torr).

[0141] Also, a film (e.g., a metal oxide coating or an aggregated polymer material, such as by the formation of a metal-oxygen-metal bond) may be deposited by ALD treatment. For example, the precursor and an optional counter-reactant are introduced at separate times representing an ALD cycle. The precursor reacts on the surface to form up to a monolayer of material at a time during each cycle. This allows for excellent control of the film thickness uniformity on the surface. The ALD treatment is generally carried out under reduced pressure, such as 0.1 Torr to 10 Torr. In some embodiments, the treatment is carried out at 1 Torr to 2 Torr. The substrate temperature may be from 0°C to 250°C, or from ambient temperature (e.g., 23°C) to 150°C. The treatment may be a heat treatment or, preferably, plasma-assisted deposition.

[0142] Any of the deposition methods herein can be modified to allow for the use of two or more different precursors. In one embodiment, the precursors may contain the same metal but different ligands. In another embodiment, the precursors may contain different metal groups. In a non-limiting example, an alternating flow of various volatile precursors, such as using a metal alkoxide precursor having a first metal (e.g., Sn) together with a silyl-based precursor having a different second metal (e.g., Te), can provide a mixed metal-containing layer.

[0143] The treatments herein can be utilized to achieve surface modification. The vapor of the precursor may be passed over the wafer for several repetitions. The wafer may be heated to provide the thermal energy for the reaction to proceed. During several repetitions, the heating may be between about 50°C and about 250°C. In some examples, pulses of the precursor are utilized and may be separated by pumping and / or purging steps. For example, a first precursor may be pulsed between pulses of a second precursor pulse to cause ALD growth or growth such as ALD. In other examples, both precursors may be flowed simultaneously. Examples of elements useful for surface modification include I, F, Sn, Bi, Sb, Te, and alloys of oxides or these compounds.

[0144] The processes described herein can be utilized to deposit thin metal oxides or metals by ALD or CVD. Examples include tin oxide (SnO x ), bismuth oxide (BiO x ), and Te. After deposition, the film may be capped with an alkyl-substituted precursor in the form of M a R b L c as described elsewhere herein. Counter-reactants may be used to better remove ligands, and multiple cycles may be repeated to ensure complete saturation of the substrate surface. The surface can then be prepared for the deposition of an EUV photosensitive film. One possible method is a method for producing a thin film of SnO x . Possible chemical reactions include the growth of SnO2 by circulating tetrakis(dimethylamino)tin and a counter-reactant (such as water or O2 plasma). After growth, a capping agent may be utilized. For example, isopropyltris(dimethylamino)tin vapor may be flowed over the surface.

[0145] The deposition process is available for any useful surface. As referred to herein, a "surface" is the surface on which the film of the present technology is deposited or the surface exposed to EUV during processing. Such a surface may be present on a substrate (e.g., on which the film is deposited) or on a film (e.g., on which a capping layer may be deposited).

[0146] Such topographical features of the underlying layer may include regions where material has been removed (e.g., by etching) or material has been added (e.g., by deposition) during processing prior to implementing the methods of this technology. Such pretreatment may include the methods of this technology or other processing methods in an iterative process in which two or more feature layers are formed on a substrate. Without limiting the mechanism, function, or usefulness of the present disclosure, in some embodiments, the methods of the present disclosure provide advantages such as matching the film of the present technology to the underlying features without "filling" or otherwise planarizing such features and being able to deposit a film on various material surfaces.

[0147] Exposure of Metal-Containing Resist Materials The photoresist film may be exposed to radiation. The photoresist film is exposed to radiation according to a desired pattern to form an exposed region and an unexposed region of the photoresist film. The "exposed region" may be understood as a relatively "exposed area", and the "unexposed region" may be understood as a relatively "unexposed area". Exposure causes changes in the chemical composition and cross-linking within the photoresist film, creating a contrast in the etching selectivity ratio that can be utilized for subsequent development.

[0148] EUV exposure of the film can provide an EUV-exposed region having activated reaction centers containing metal atoms (M), and those reaction centers are generated by cleavage events by EUV. Such reaction centers can include metal dangling bonds, M-H groups, cleaved M-ligand groups, dimerized M-M bonds, or M-O-M bridges.

[0149] EUV exposure may have a wavelength in the range of about 10 nm to about 20 nm (a wavelength of 10 nm to 15 nm (e.g., 13.5 nm)) in a vacuum atmosphere. In particular, patterning can provide an EUV-exposed region and an EUV-unexposed region for forming a pattern. In some embodiments, such patterning includes a radiation dose of about 1 to 50 mJ / cm2, 1 to 40 mJ / cm 2 , 1 to 30 mJ / cm 2 , 1 to 20 mJ / cm 2 , or 1 to 10 mJ / cm 2 .

[0150] This disclosure includes not only patterning using EUV, but also patterning using DUV or an electron beam. In such patterning, radiation is focused onto one or more regions of an imaging layer. The exposure can be performed such that the imaging layer film includes one or more regions that are not exposed to the radiation. The resulting imaging layer includes a plurality of exposed and unexposed regions, and thus can create a pattern that conforms to the creation of transistors or other features of a semiconductor device formed by adding or removing material to or from a substrate in subsequent processing of the substrate. Methods and apparatuses for EUV, DUV, and electron beam radiation, among those useful herein, include methods and apparatuses well known in the art.

[0151] In some EUV lithography techniques, an organic hard mask (e.g., an ashingable hard mask of PECVD amorphous hydrogenated carbon) is patterned using photoresist processing. During photoresist exposure, EUV radiation is absorbed by the resist and the underlying substrate, generating high-energy photoelectrons (e.g., about 100 eV), which then generate a cascade of low-energy secondary electrons (e.g., about 10 eV) that diffuse laterally by only a few nanometers. These electrons increase the degree of progress of chemical reactions that enhance EUV dose sensitivity in the resist. However, the inherently random secondary electron pattern is superimposed on the optical image. This unwanted secondary electron exposure causes a reduction in resolution, observable line edge roughness (LER), and linewidth variation in the patterned resist. These defects are transferred to the material being patterned during subsequent pattern transfer etching.

[0152] In various embodiments described herein, a deposition (e.g., condensation) process (e.g., ALD or MOCVD performed in a PECVD tool) can be utilized to form a thin film of a metal-containing film, such as a photosensitive metal salt or a metal-containing organic compound (organometallic compound) that has a strong absorption effect on EUV (e.g., wavelengths on the order of 10 nm to 20 nm) at the wavelength of an EUVL light source (e.g., 13.5 nm = 91.8 eV). This film is photodecomposed during EUV exposure to form a metal mask, which is a pattern transfer layer, during subsequent etching (e.g., within a conductor etch tool).

[0153] After deposition, the EUV-patternable thin film is patterned in some examples by exposure to a beam of EUV light under a relatively high vacuum. Subsequently, for EUV exposure, the metal-containing film can be deposited in a chamber integrated with a lithography platform (e.g., a wafer stepper) and transported under vacuum so as not to react prior to exposure. The integration with a lithography tool is facilitated by the fact that EUVL also requires a very low pressure, given that strong light absorption of incident photons by ambient gases (H2O, O2, etc.) is assumed. In other embodiments, the photosensitive metal film deposition and EUV exposure may be performed in the same chamber.

[0154] The photolithography process can include one or more bake steps to facilitate the chemical reactions necessary to create a chemical contrast between the exposed and unexposed regions of the photoresist. In high-volume manufacturing (HVM), such bake steps can be performed on a track where the wafer is baked on a hotplate at a preset temperature under ambient air or, in some cases, a N2 flow. By more carefully controlling the bake atmosphere and introducing additional reactive gas components into the atmosphere during these bake steps, it can help reduce the required dose further and / or improve pattern fidelity.

[0155] According to various aspects of the present disclosure, one or more post-treatments on metal and / or metal oxide-based photoresists after deposition (e.g., post-application bake (PAB) or another post-application treatment) and / or after exposure (e.g., post-exposure bake (PEB) (which may be omitted) or another post-exposure treatment) and / or after development (e.g., post-development bake (PDB) or another post-development treatment) can increase the difference in material properties between the exposed photoresist and the unexposed photoresist, thus reducing the dose-to-size (DtS), improving the PR profile, and improving the line edge roughness and line width roughness (LER / LWR) after subsequent dry development. Such treatments can include heat treatment along with control of temperature, gas atmosphere, and humidity to improve the performance of dry development in subsequent processes. In some examples, remote plasma may be used. However, in certain examples, PAB and / or PEB and / or PDB are not performed.

[0156] In the case of a post-application treatment (e.g., PAB), heat treatment can be used along with control of temperature (e.g., control by heating or cooling), gas atmosphere (e.g., air, H2O, CO2, CO, O2, O3, CH4, CH3OH, N2, H2, NH3, N2O, NO, Ar, He, or a mixture thereof) or under vacuum, and humidity to change the composition of the unexposed metal and / or metal oxide photoresist before exposure after deposition. Such a change can enhance the EUV sensitivity of the material, so that lower dose-to-size and edge roughness can be achieved after exposure and dry development.

[0157] In the case of post-exposure treatment (e.g., PEB), heat treatment can be used under temperature, gas atmosphere (e.g., air, H2O, CO2, CO, O2, O3, CH4, CH3OH, N2, H2, NH3, N2O, NO, Ar, He, or a mixture thereof), or vacuum, along with control of humidity, to change the composition of both unexposed and exposed photoresists. Such changes can increase the difference in composition / material properties between the unexposed and exposed photoresists, as well as the difference in etching rates of dry development etching gases between the unexposed and exposed photoresists. Thereby, a higher etching selectivity can be achieved. With the improved selectivity, a PR profile closer to square can be obtained with improved surface roughness and / or less photoresist residue / scum. In certain embodiments, PEB can be performed in air, optionally in the presence of water vapor and CO2. In other embodiments, PEB may be omitted.

[0158] In the case of post-development treatment (e.g., post-development bake i.e., PDB), heat treatment can be used under temperature, gas atmosphere (e.g., air, H2O, CO2, CO, O2, O3, CH4, CH3OH, N2, H2, NH3, N2O, NO, Ar, He, or a mixture thereof), or vacuum (e.g., with UV), along with control of humidity, to change the composition of the unexposed photoresist. In certain embodiments, the conditions further include the use of plasma (e.g., including O2, O3, H2O2, Ar, He, or a mixture thereof). Such changes can increase the hardness of the material, which can be useful when the film is used as a resist mask when etching the underlying substrate.

[0159] In these cases, in another example, the heat treatment may be replaced by remote plasma treatment to lower the energy barrier for the reaction and increase productivity by increasing the reactive species. Remote plasma can generate more reactive radicals, so it can reduce the reaction temperature / time of the treatment, leading to an improvement in productivity.

[0160] Accordingly, one or more processes may be applied to modify the photoresist itself to increase the wet or dry development selectivity ratio. This thermal or radical modification can increase the contrast between the unexposed material and the exposed material, and thus can increase the selectivity ratio of subsequent development processes. The resulting difference in material properties between the unexposed material and the exposed material can be adjusted by adjusting process conditions including temperature, gas flow rate, humidity, pressure, and / or RF power.

[0161] For a wet-developed or dry-developed resist film, the PAB or PEB treatment temperature can be changed, for example, to about 90°C to 250°C for PAB and to about 170°C to 250°C or higher for PEB, to adjust and optimize the treatment process.

[0162] In certain embodiments, the PAB and / or PEB treatment may be performed at a gas ambient flow rate in the range of 100 sccm to 10,000 sccm, a humidity of several percent to up to 100% (e.g., 20% to 50%), a pressure between atmospheric pressure and vacuum, and a duration of about 30 seconds to 15 minutes (e.g., about 1 to 2 minutes). In certain embodiments, PEB is omitted.

[0163] Depending on the requirements / constraints of the selectivity ratio of semiconductor processing operations, the necessary EUV dose can be reduced using heat treatment as described herein. Alternatively, if a higher selectivity ratio is required and a higher dose can be tolerated, a much higher selectivity ratio (up to 100 times the selectivity ratio of the exposed part to the unexposed part) can be obtained.

[0164] Still other processes may include in-situ measurements that can evaluate physical and structural characteristics (e.g., critical dimension, film thickness, etc.) during photolithography processing. Modules for realizing in-situ measurements include, for example, a scatterometer, a deflection analysis, a downstream mass spectrometry, and / or a plasma-enhanced downstream emission spectroscopy module.

[0165] A substrate may be provided in a processing chamber, where the substrate is a semiconductor substrate comprising a substrate layer and a post-development photoresist mask covering the substrate layer. The substrate layer may be beneath the post-development photoresist mask and may comprise any suitable material to facilitate patterning processes. The substrate layer may be etched with a high selectivity with respect to the post-development photoresist mask. In some embodiments, the one or more substrate layers comprise spin-on carbon (SoC), spin-on glass (SOG), amorphous carbon (a-C), amorphous silicon (a-Si), tin oxide (e.g., S n O x ), silicon (a-Si), silicon oxide (e.g., SiO x ), silicon oxynitride (e.g., SiO x N y ), silicon oxycarbide (e.g., SiO x C y ), silicon nitride (e.g., Si3N4), silicon carbide (SiC x ), titanium oxide (e.g., TiO2), titanium nitride (e.g., TiN), tungsten (e.g., W), doped carbon (e.g., W-doped C), tungsten oxide (e.g., WO x ), hafnium oxide (HfO2), zirconium oxide (e.g., ZrO2), or aluminum oxide (e.g., Al2O3).

[0166] The metal-containing photoresist may be dry or wet deposited on the substrate layer. The metal-containing photoresist may be provided as a positive-tone resist or a negative-tone resist having EUV-exposed regions and EUV-unexposed regions after EUV exposure. After deposition, the metal-containing photoresist may be photopatterned within an EUV lithography chamber (scanner). After exposure and optional PEB treatment, the metal-containing photoresist may be developed to selectively remove portions of the metal-containing photoresist (e.g., EUV-unexposed portions) to form a patterned photoresist mask on the substrate layer. In some embodiments, the metal-containing photoresist is a metal-containing EUV photoresist, where the metal-containing EUV photoresist is an organometallic oxide or an organometallic-containing film. For example, the metal-containing EUV photoresist may contain Sn, O, and C atoms.

[0167] The processing chamber can provide a sealed space for processing the substrate after development. The chamber walls of the processing chamber may be made of stainless steel, aluminum, plastic, or other suitable materials. In some embodiments, the chamber walls are coated with a corrosion-resistant film (such as a polymer or an inorganic coating). The processing chamber may include a substrate support (e.g., a pedestal or an electrostatic chuck) on which the substrate is supported. In some embodiments, the processing chamber for post-development processing may be a deposition chamber, a bevel edge and / or backside cleaning chamber, a PAB processing chamber, a PEB processing chamber, a development chamber, or an etching chamber. Thus, the processing chamber for post-development processing may be the same chamber used in a previous operation for photoresist processing or the same chamber used in a subsequent operation for photoresist processing, thereby reducing exposure to air breaks (changes in air) between operations by minimizing the transfer of the substrate. The processing chamber may include one or more heating elements for exposing the substrate to a high temperature. In some embodiments, the one or more heating elements may include one or more infrared (IR) lamps or one or more light-emitting diodes (LEDs) disposed on the substrate support to control the temperature of the substrate. The processing chamber may include one or more gas lines for transporting gas into the processing chamber. For example, the one or more gas lines may include a showerhead for supplying a reactive gas toward the substrate within the processing chamber. In some examples, the processing chamber may be a plasma generation chamber or may be coupled to a plasma generation chamber separate from the processing chamber. The plasma generation chamber may be an inductively coupled plasma (ICP) reactor, a capacitively coupled plasma (CCP) reactor, or a capacitively coupled plasma (CCP) reactor. In some cases, the processing chamber further includes one or more gas outlets for exhausting gas, and the gas outlets may or may not be coupled to a vacuum pump for maintaining a desired pressure within the processing chamber.

[0168] The developed metal-containing photoresist mask is processed using one or more of the following operations: (i) an operation of thermally annealing the developed metal-containing photoresist mask, (ii) an operation of exposing the developed metal-containing photoresist mask to plasma, (iii) an operation of exposing the developed metal-containing photoresist mask to one or more reactive gases, and (iv) an operation of selectively depositing a protective layer on the developed metal-containing photoresist mask. The post-development processing of the substrate may utilize one of the above-described thermal annealing process, plasma process, chemical process, or selective deposition process operation, or a combination of the above-described processes. The post-development processing improves the performance of the metal-containing photoresist mask during pattern transfer etching. The above-described thermal annealing process, plasma process, chemical process, and selective deposition process technologies will be discussed in detail later.

[0169] The substrate layer is etched using the developed metal-containing photoresist mask to form recessed features. This process may be referred to as pattern transfer or pattern transfer etching. The etching can selectively remove portions of the substrate layer without removing the developed metal-containing photoresist mask. A wet or dry etchant may be used to etch the portions of the substrate layer exposed by the developed metal-containing photoresist mask. The metal-containing photoresist mask may define the pattern in which the features are etched. The features are etched into the substrate layer according to the pattern defined by the metal-containing photoresist mask. After the post-development processing, the metal-containing photoresist mask may have an increased line CD and / or improved etching resistance during pattern transfer etching. The features being etched can maintain or substantially maintain the line CD provided by the metal-containing photoresist mask. In some cases, the metal-containing photoresist mask may have reduced defects and / or roughness. As a result, the defects and roughness do not transfer to the features formed after pattern transfer etching.

[0170] Heat Treatment In some embodiments, the substrate may be heat treated by heating the substrate to a high temperature. This may also be referred to as post - development bake (PDB). The heat treatment of the substrate can function to reduce defects and roughness from the metal - containing photoresist mask prior to pattern transfer etching. In particular, the heat treatment of the substrate can improve the chemical contrast in the metal - containing photoresist mask by removing scum. The heat treatment of the substrate can cure residues / scum and also reduce gas evolution.

[0171] After wet or dry development, residues or scum can remain on the substrate. Residues or scum can remain in the areas of the photoresist mask that have been removed by development. Residues or scum can include residual etching by - products adsorbed on the surface of the substrate. For example, the vapor of a halogen used in a particular developer can react with moisture or oxygen to form residual etching by - products that are difficult to remove. Wet - processing techniques often utilize moisture and / or oxygen, which can more readily lead to the formation of scum and residues. In some cases, residues can contribute to the loss of chemical contrast during pattern transfer and can contaminate downstream processing tools with high metal concentrations of metal oxides (e.g., SnO x ) or particles or clusters.

[0172] After wet or dry development, roughness can occur on the sidewalls of the etched features in the developed pattern of the photoresist mask. Some of this can be due to the probability theory of light or non - optimal Gaussian distribution, such that the material is partially or completely exposed in an area where the photoresist should remain unexposed, or vice versa. Additionally, scum formation on the sidewalls of the etched features of the photoresist mask can worsen the roughness.

[0173] During heat treatment, the substrate may be heated to a high temperature between about 50°C and about 500°C, between about 100°C and about 400°C, between about 100°C and about 300°C, or between about 100°C and about 250°C. The substrate may be heated to a high temperature using one or more temperature controllable elements within the processing chamber. The pressure may be maintained between about 0.1 Torr and about 760 Torr (e.g., in some cases, between about 0.1 Torr and about 1 Torr). The substrate may be exposed to a high temperature for a duration between about 1 minute and about 10 minutes (e.g., in some cases, between about 2 minutes and about 5 minutes). In some embodiments, the heat treatment is performed using one or more inert gases. For example, the heat treatment may be performed using a flow of nitrogen (N2), helium (He), neon (Ne), argon (Ar), or xenon (Xe). In some embodiments, the heat treatment is performed in air.

[0174] Higher temperatures in post-development heat treatment can lead to an increase in desmearing, a reduction in defects, and a reduction in roughness. However, higher temperatures can simultaneously lead to a decrease in line CD. It has been observed that higher temperatures during thermal annealing cause lateral shrinkage of the photoresist and shrinkage of the photoresist height. The decreased line CD leads to a higher dose-to-size. Post-development heat treatment can have a trade-off problem between defect and roughness reduction and a higher dose-to-size. This limits the heat treatment to a desired temperature range and a desired processing duration in order to optimize the benefits of defect and roughness reduction while minimizing the increase in dose-to-size.

[0175] Plasma Treatment In some embodiments, the substrate may be exposed to plasma for post-development processing. The plasma treatment may function to increase the density and reduce the roughness of the metal-containing photoresist mask prior to pattern transfer etching. In some cases, the plasma treatment may further improve the chemical contrast in the metal-containing photoresist mask by removing scum. The plasma treatment may use a plasma of inert gas species or a plasma of reactive gas species. The plasma of reactive gas species may chemically react with the metal-containing photoresist mask or selectively deposit a protective film on the metal-containing photoresist mask. The plasma treatment may have the effect of passivation and / or curing.

[0176] Exposure to plasma may be carried out by generating plasma in a remote plasma generator or in the processing chamber where the substrate is being processed. One or more gases may be flowed into the plasma generation region, which may be the remote plasma generator or the processing chamber, where the plasma is ignited. The plasma generation chamber may be an inductively coupled plasma (ICP), capacitively coupled plasma (CCP), or transformer coupled plasma (TCP) reactor. Plasma energy is provided to activate one or more gases into ions, radicals, neutral species, and other plasma-activated species. The ions, radicals, neutral species, and other plasma-activated species may interact with the metal-containing photoresist mask to improve the performance of the metal-containing photoresist mask during pattern transfer etching.

[0177] The one or more gases may include oxygen-containing species such as oxygen (O2), carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), and sulfur dioxide (SO2). Additionally or alternatively, the one or more gases may include halogen-containing species such as boron trichloride (BCl3), silicon tetrachloride (SiCl4), tin tetrachloride (SnCl4), tungsten hexafluoride (WF6), and difluoromethane (CH2F2). Additionally or alternatively, the one or more gases may include inert gas species such as nitrogen (N2), helium (He), neon (Ne), argon (Ar), and xenon (Xe). Other gases may include hydrogen (H2), ammonia (NH3), water (H2O), hydrogen peroxide (H2O2), nitric oxide (NO), nitrous oxide (N2O), nitrogen dioxide (NO2), hydrogen halides (HCl, HBr, HF, HI), and various carbohydrates (C x H y )(such as methane (CH4)). In some cases, the plasma may be an oxygen-based plasma, a nitrogen-based plasma, a hydrogen-based plasma, an inert gas plasma, and / or a carbon-based plasma. In some embodiments, the plasma is a remote plasma. In some other embodiments, the plasma is an in-situ plasma.

[0178] The processing conditions of the plasma treatment may be adjusted to achieve the desired results. Such processing conditions include, but are not limited to, plasma power, plasma frequency, plasma exposure time, bias voltage, duty cycle, temperature (e.g., pedestal temperature), pressure (e.g., chamber pressure), and the flow rate of one or more gases. The plasma during operation may be generated at a plasma power of less than about 6 kW, such as between about 50 W and about 4000 W, between about 50 W and about 1000 W, or between about 100 W and about 500 W. In some examples, the plasma may be provided at low plasma power and high ion energy. The directionality of the plasma may be controlled by the bias voltage. In some embodiments, a bias voltage between about 1 V and about 500 V, between about 10 V and about 400 V, or between about 30 V and about 300 V may be applied. The plasma treatment may be performed over a duration between about 0.5 seconds and about 120 seconds, between about 1 second and about 60 seconds, or between about 2 seconds and about 40 seconds. The plasma treatment may adjust the duty cycle of the plasma during operation to achieve the desired results, where the RF power supply may supply the plasma at any suitable duty cycle (such as between about 1% and about 99%, or between about 10% and about 90%, etc.). In some embodiments, the chamber pressure may be between about 0.1 Torr and about 760 Torr, or in some cases between about 0.1 Torr and about 1 Torr. In some embodiments, the substrate temperature may be between about 0 °C and about 400 °C, between about 50 °C and about 300 °C, or between about 100 °C and about 250 °C.

[0179] In some embodiments, a useful plasma processing system may comprise a high-frequency power amplifier operable in continuous or pulsed mode.

[0180] As discussed below, plasma treatment may be achieved by reactive gas species. The plasma of the reactive gas species may induce a chemical reaction within the metal-containing photoresist mask so as to improve mask characteristics (such as etching resistance). The plasma of the reactive gas species may selectively deposit a protective film on the metal-containing photoresist mask so as to increase the line CD and decrease the dose-to-size.

[0181] In certain embodiments, the plasma treatment may be a cyclic plasma treatment. Such treatment includes a first step of soaking in a halogen-containing gas such as HBr, where HBr is absorbed by the exposed patterned surface, and then an excess of HBr is purged. After purging the processing chamber, the second step of the cyclic plasma treatment process ignites a helium plasma at a specific bias to activate the HBr absorbed on the exposed patterned surface for the purpose of descumming. Then, the two steps are repeated the number of times necessary to remove all scum.

[0182] In certain embodiments, the plasma treatment may be a continuous plasma dry development. In this treatment, an inert gas including but not limited to helium, argon, or a combination thereof is simultaneously flowed into the processing chamber together with a halogen-containing gas (such as HBr) of about 1 to about 10 percent, and then the plasma is ignited at a bias of a voltage of about 40 volts to about 500 volts for descumming. The flow rate of the halogen-containing gas may be about 200 to about 800 sccm. The plasma is adjustable by 1) ramping up the TCP power from high to low, 2) maintaining a constant TCP power regardless of the pulsed bias, or 3) simultaneously pulsing the bias and TCP to remove scum from the photoresist surface. The entire treatment may take about 7 to about 30 seconds in some embodiments. The pressure of the continuous dry development plasma treatment may be about 5 mTorr to about 50 mTorr.

[0183] Chemical Treatment In some embodiments, the metal-containing photoresist mask may be exposed to one or more reactive gas species. The reactive gas species may chemically react with the metal-containing photoresist mask. In fact, certain reactive gas species may react with the metal-containing photoresist mask and not with the substrate layer of the substrate. In some embodiments, the reactive gas may convert all or substantially all of the metal-containing photoresist mask from a first material to a second material. The chemical change of the metal-containing photoresist mask may change one or more properties of the metal-containing photoresist mask. In some embodiments, the reactive gas species may convert only the outer portion of the metal-containing photoresist mask from a first material to a second material, which may be used as a protective film, as will be described in detail later.

[0184] The reactive gas species may react with the metal-containing photoresist mask to increase the line CD and decrease the dose-to-size. The reactive gas species may react with the metal-containing photoresist mask to reduce the roughness (e.g., LWR / LER) or at least maintain the same roughness. The reactive gas species may increase the density of the metal-containing photoresist mask. In some cases, the reactive gas species may react with the metal-containing photoresist mask to reduce defects (e.g., scumming). Further, the reactive gas species may reduce gas evolution such as the gas evolution of tin from the metal-containing photoresist mask. In some cases, the reactive gas species may react with the metal-containing photoresist mask to increase the etching resistance of the photoresist mask during a subsequent etching operation. As an example, the reactive gas species may increase the line CD and at least substantially maintain the high line CD of the photoresist mask after pattern transfer etching.

[0185] The reaction gas species can react with the metal-containing photoresist more than the substrate layer in the lower layer. In certain embodiments, the chemical treatment using the reaction gas species utilizes the chemical properties of the EUV photoresist mask. The EUV photoresist mask can be composed of an organometallic oxide film (such as an organotin oxide film) having Sn, O, and C atoms. The organotin oxide film can be composed of a network of Sn-Sn bonds, Sn-H bonds, Sn-C bonds, Sn-OH bonds, Sn-O bonds, Sn-O-Sn bonds, and Sn-O-C bonds. The reaction gas species can react with one or more elements of the organotin oxide film by oxidation, reduction, insertion, extraction, or other chemical reaction mechanisms so as to induce chemical changes in the EUV photoresist mask. In some examples, the reaction gas species may include carbon monoxide (CO), where the tin species can catalytically react with carbon monoxide. Without being limited by any theory, the compound SnOC x reacts with CO to form a new compound SnOC x (CO) y . The chemical reaction induces changes in the EUV photoresist mask by expanding line CD. In some embodiments, the etching resistance of the new compound in the EUV photoresist mask is improved.

[0186] Reaction gas species other than CO may be used to induce chemical reactions in EUV photoresist masks. Examples of useful reaction gas species may include, but are not limited to, air, water vapor (H2O), hydrogen peroxide (H2O2), carbon dioxide (CO2), oxygen (O2), ozone (O3), methane (CH4), methanol (CH3OH), ethanol (CH3CH2OH), nitrogen (N2), hydrogen (H2), ammonia (NH3), nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), acetylacetone (C5H8O2), formic acid (CH2O2), acetic acid (CH3COOH), hydrogen cyanide (HCN), boron trichloride (BCl3), silicon tetrachloride (SiCl4), chlorine (Cl2), bromine (Br2), hydrogen chloride (HCl), hydrogen bromide (HBr), hydrogen iodide (HI), hydrogen fluoride (HF), fluoromethane (CH3F), difluoromethane (CH2F2), and combinations thereof. In some cases, the reaction gas species may include an oxygen-containing gas, a carbon-containing gas, a hydrogen-containing gas, a nitrogen-containing gas, a halogen-containing gas, or combinations thereof. Other reaction gas species may include metal precursors such as tungsten hexafluoride (WF6), tin tetrachloride (SnCl4), molybdenum hexafluoride (MoF6), molybdenum dioxide dichloride (MoO2Cl2), and molybdenum pentachloride (MoCl5). Other reaction gas species may include tetrakis(dimethylamido)tin (Sn(N(CH3)2)4), tetrakis(dimethylamido)hafnium (Hf(N(CH3)2)4), dimethylaluminum ((CH3)2Al), trimethylaluminum ((CH3)3Al), titanium isopropoxide (Ti(OCH(CH3)2)4), tungsten carbonyl (W(CO x ))), molybdenum carbonyl (Mo(CO) x ), ruthenium carbonyl (Ru(CO) x ), iron carbonyl (Fe(CO) x) and combinations thereof, etc., may include metal organic precursors. Thus, in some cases, the reactive gas species may include metal halides or organometallic precursors (such as metal carbonyl precursors). Conventional polymer-based photoresist materials cannot react with metal halides or specific organometallic precursors, but the metal-containing photoresist materials or metal oxide-containing photoresist materials of the present disclosure may tend to react more with metal halides and organometallic precursors. Without being limited by any theory, when there is an M-OH bond in the organometallic photoresist, an M-O-M' crosslink may be formed, where M' is derived from a metal precursor (for example, a metal halide or an organometallic precursor).

[0187] The reactive gas species may be flowed simultaneously with other gases. In some embodiments, the reactive gas species may be flowed simultaneously with an inert gas species (such as helium, neon, argon, or xenon). In some embodiments, combinations of reactive gas species may be flowed simultaneously with each other. As an example, a halogen-containing gas such as boron trichloride may be flowed simultaneously with a carbon-containing gas such as methane. In another example, a metal precursor such as tungsten hexafluoride may be flowed simultaneously with a carbon-containing gas such as difluoromethane. The reactive gas species, alone or with other reactive gas species, may convert a photoresist mask into another material or selectively deposit a protective film on the photoresist mask.

[0188] In some embodiments, the reactive gas species may be supplied from a gas source fluidly connected to the processing chamber to the processing chamber. The gas source (such as a gas storage tank) may be fluidly connected to the processing chamber via a gas supply line. The gas reactants may be pre-mixed before entering the processing chamber or may be mixed when entering the processing chamber. In some embodiments, the reactive gas species may be generated in-situ in the processing chamber. The gas reactants may react with each other to form reaction products that react with the metal-containing photoresist mask to induce a chemical change. Alternatively, the gas reactants may react with one or more chamber components (e.g., metal-based chamber lines) to form reaction products that react with the metal-containing photoresist mask to induce a chemical change. The gas reactants may be carbon-containing precursors that react with the metal chamber components to form organometallic precursors. This reaction may be thermally driven to produce organometallic precursors. For example, carbon monoxide supplied to the processing chamber may react with an iron-containing chamber line to form iron carbonyl (Fe(CO) x ) that readily reacts with the EUV photoresist mask, thereby increasing the line CD of the EUV photoresist mask. Without being limited by any theory, iron carbonyl causes the deposition of iron oxide onto the EUV photoresist mask. In another example, carbon monoxide or carbon dioxide supplied to the processing chamber may react with a tungsten-containing chamber line (e.g., a hot wire) to form tungsten carbonyl (W(CO) x ) that readily reacts with the EUV photoresist mask.

[0189] The chemical treatment of a metal-containing photoresist mask using one or more reactive gas species may be used in conjunction with one or both of heat treatment and plasma treatment. Heat treatment or plasma treatment alone may exhibit a trade-off, but such a trade-off can be offset by further applying chemical treatment to the metal-containing photoresist mask. Specifically, the chemical treatment may be combined with heat treatment such that one or more reactive gas species are flowed over the metal-containing photoresist mask at a high temperature. The high temperature may reduce line CD, but one or more reactive gas species may increase line CD within the metal-containing photoresist mask. In fact, the line CD increased due to one or more reactive gas species may exceed the line CD decreased due to the high temperature. This reduces the defects and roughness within the metal-containing photoresist mask while reducing the dose-to-size. In some embodiments, the chemical treatment may be combined with plasma treatment such that radicals and / or ions of the reactive gas species are flowed over the metal-containing photoresist mask. The radicals and / or ions may enhance the reactivity between the reactive gas species and the metal-containing photoresist mask. The metal-containing photoresist mask may be exposed to one or more reactive gas species within the plasma, which may change the chemical composition of the metal-containing photoresist mask and increase the line CD and density. This may be done without necessarily worsening the defects or roughness of the metal-containing photoresist mask. The plasma may be applied at a power such as to avoid damage to the substrate.

[0190] The induction of surface reactions or bulk reactions in a metal-containing photoresist mask can occur by applying energy to the reaction. A certain amount of energy from thermal exposure and / or plasma exposure may be sufficient to induce surface or bulk reactions. Thus, the processing conditions (such as temperature and plasma power) may be adjusted to achieve the desired results. In some embodiments, the substrate temperature may be between about 0°C and about 400°C, between about 50°C and about 300°C, or between about 100°C and about 250°C during chemical processing with one or more gas species. In some embodiments, the plasma power may be less than about 6 kW, between about 50 W and about 4000 W, between about 50 W and about 1000 W, or between about 100 W and about 500 W during chemical processing with one or more reactive gas species.

[0191] Other processing conditions (such as plasma frequency, exposure time, bias voltage, pressure, and flow rate, etc.) may be adjusted to facilitate chemical processing using one or more reaction gas species. In some embodiments, a bias voltage of less than about 800 V, between about 0 V and about 500 V, between about 10 V and about 400 V, or between about 30 V and about 300 V may be applied. In some embodiments, exposure to one or more reaction gas species may be carried out over a duration between about 1 second and about 10 minutes, between about 5 seconds and about 8 minutes, or between about 30 seconds and about 4 minutes. In some embodiments, the chamber pressure may be between about 0.1 Torr and about 760 Torr, or in some cases between about 1 mTorr and about 100 mTorr. The first reaction gas species may be flowed into the processing chamber at a flow rate between about 1 sccm and about 1000 sccm, between about 2 sccm and about 500 sccm, or between about 5 sccm and about 300 sccm. An optional second reaction gas species may be simultaneously flowed into the processing chamber at a flow rate between about 5 sccm and about 1000 sccm, between about 10 sccm and about 500 sccm, or between about 20 sccm and about 300 sccm. An optional inert gas species may be simultaneously flowed into the processing chamber at a flow rate between about 20 sccm and about 2000 sccm, between about 30 sccm and about 1000 sccm, or between about 50 sccm and about 500 sccm. As an example, carbon monoxide may be flowed into the processing chamber at a flow rate of about 500 sccm over a duration between about 20 seconds and about 5 minutes at a substrate temperature of about 240 °C. Carbon monoxide can react with the EUV photoresist mask to change the chemical composition of the EUV photoresist mask. In another example, tungsten hexafluoride may react with the EUV photoresist mask instead of carbon monoxide to change the chemical composition of the photoresist mask. The EUV photoresist mask may exhibit increased etching resistance during subsequent pattern transfer etching.

[0192] Certain embodiments of the disclosed method are shown in FIG. 3. The operations of process 300 may be executed in a different order and / or with different, fewer, or additional operations. One or more of the operations of process 300 may be executed using the apparatus described in any of FIGS. 6-9. In some embodiments, the operations of process 300 may be implemented, at least in part, in accordance with software stored on one or more non-transitory computer-readable media.

[0193] In FIG. 3, blocks 302-310 and 314 represent the same operations as blocks 102-110 and 116 of FIG. 1. The operation of block 312 represents an integrated dry development operation, where the integrated dry development operation may include thermal and plasma dry development, or the integrated dry development operation may include dry development and post-development processing, and all operations are performed within a single processing chamber. The operation 312 may be executed instead of operations 112 and 114 of FIG. 1. By doing so, productivity can be improved and defects, overlays, and CDs can be more effectively controlled. Aggregating all dry development and post-development operations into one processing chamber promotes the reduction of metal gas emissions (such as tin gas emissions) without the need to add an additional step of post-development baking, which was conventionally performed in a separate processing chamber.

[0194] The combination of dry development and passivation or the combination of thermal dry development and plasma dry development in a single chamber is counterintuitive, especially with respect to pressure, due to the diametrically opposed processing conditions required for each operation. Conventionally, they have been carried out in different chambers with different processing tools to practically manage the pressure requirements. Heat treatment requires high pressure to obtain high etching rates. Higher partial pressures lead to better selectivity. Conversely, for plasma processing, low pressure is required to achieve anisotropic etching. When carried out in a single processing chamber, a pressure drop of several orders of magnitude must be achieved rapidly, within about 1 to about 10 seconds. The use of a throttle valve, a dedicated pump, multiple pumps, or flow control of the processing gas can result in a rapid pressure drop on the order of 10 seconds or less. In some embodiments, the pressure drop is made in 8 seconds, 7 seconds, 6 seconds, 5 seconds, 4 seconds, 3 seconds, or 2 seconds. The apparatus enables the uniform maintenance of one or more processing parameters, where the one or more processing parameters include pumping, gas supply, or pumping and gas supply.

[0195] Furthermore, the all-in-one process enables in-situ passivation of the wafer surface, residue cleaning, and smoothing of pattern edge roughness within a single chamber.

[0196] When the metal-containing photoresist is a metal oxide (such as tin oxide), metal gas evolution (such as tin gas evolution) can be controlled without the need for a post dry etching bake.

[0197] "Tin oxide" as used herein is considered to include anything stoichiometrically possible for Sn with integer values of x and y as well as non-integer values of x and y. For example, "tin oxide" includes compounds having the chemical formula SnO x O y and is considered to include everything possible. For example, "tin oxide" includes compounds having the chemical formula SnO n where 1 ≦ n ≦ 2 and n can be an integer value or a non-integer value. "Tin oxide" includes metastoichiometric compounds (SnO 1.8may include, etc. "Tin oxide" includes both tin dioxide (SnO2 or stannic oxide) and tin monoxide (SnO or stannous oxide). "Tin oxide" includes both natural and synthetic variations and includes all crystal and molecular structures. "Tin oxide" also includes amorphous tin oxide.

[0198] Examples of methods for performing the integrated operations of block 312 will be described in more detail in FIGS. 4A, 4B, 4C, 4D, and 4E. The embodiments described in FIGS. 4A, 4B, 4C, 4D, and 4E are intended to be merely illustrative and are not intended to be limiting to the scope of block 312 of process 300. FIG. 4A may depict one aspect of block 312 where dry development and passivation are performed in the same processing chamber. FIG. 4B may depict one aspect of block 312 where thermal dry development and plasma dry development are performed in the same processing chamber. FIG. 4C may depict one aspect of block 312 where dry development and curing are performed in the same processing chamber. FIG. 4D may depict one aspect of block 312 where thermal dry development, plasma dry development, and passivation are performed in the same processing chamber. FIG. 4E may depict one aspect of block 312 where thermal dry development, plasma dry development, passivation, and curing are performed in the same processing chamber.

[0199] FIG. 4A is a flowchart of a process example 410 for performing dry development and passivation operations in the same processing chamber according to a particular disclosed embodiment. For some photoresists, under some processing conditions, only thermal dry development processing is required. That is, plasma dry development may not be necessary.

[0200] The operation of block 412 may be a dry development process. As described herein, a dry development process may be utilized to process a photoresist film. Non-limiting processes may include the use of halides such as hydrogen halides (e.g., HBr, HCl, etc.), hydrogen and halogen gases (e.g., H2 and Cl2, H2 and Br2, etc.), boron trichloride, organic halides, acyl halides, carbonyl halides, thionyl halides, or mixtures thereof. The present disclosure is not limited to any particular theory or mechanism of operation, but the approach is understood to utilize the chemical reactivity of an EUV photoresist film with a cleaning agent (e.g., HCl, HI, HBr, and / or BCl3) to form volatile products using vapor or plasma. Such volatile products may be removed by any method (e.g., by treatment with an aqueous acid as described herein). The EUV photoresist film may be removed at an etching rate of up to 1 nm / second. Such rapid removal of the EUV photoresist film by these chemical actions is applicable to chamber cleaning, backside cleaning, bevel edge cleaning, and PR development. The film may be removed using vapors at various temperatures (e.g., HCl or HBr at a temperature higher than -20°C, or BCl3 at a temperature higher than 50°C), but plasma may be used to further accelerate or enhance the reactivity.

[0201] The dry development process may include a heat treatment, a plasma treatment, or a combination of a heat treatment and a plasma treatment. The heat treatment may expose the photoresist film to a process gas that may include one or more halides in a treatment without plasma. The plasma treatment may expose the photoresist film to a plasma of an inert gas, a halogen-containing gas, or a combination of an inert gas and a halogen-containing gas. Thermal dry development and plasma dry development may be performed in the same processing chamber at block 412. In negative tone development, the dry development process selectively removes less-exposed regions of the photoresist film relative to more-exposed regions of the photoresist film.

[0202] In some embodiments, the dry development is only thermal dry development. Between blocks 412 and 414, the flow path 413 may represent a change in processing conditions for transitioning from dry development at block 412 to passivation at block 414. For example, the flow path 413 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, enabling both high-pressure processing and low-pressure processing to be performed in the same chamber. The pressure change may be managed by a throttle valve, a dedicated pump, multiple pumps, flow control of the processing gas, or a combination of these techniques. When two or more pumps are utilized, one of the pumps may be a roughing pump and one of the pumps may be a turbo pump. An optional purge with an inert gas may be performed before, after, or during the pressure drop operation.

[0203] After dry development at block 412, the operation at block 414 represents a passivation step (such as flash plasma treatment). Dry development at block 412 and passivation at block 414 may be performed in the same processing chamber. In some embodiments, dry development at block 412 may be performed at a first pressure and passivation at block 414 may be performed at a second pressure. For example, the second pressure may be less than or equal to the first pressure. In some embodiments, the first pressure is in the range between about 5 mTorr and about 760 Torr, and the second pressure is in the range between about 5 mTorr and about 200 mTorr. In some embodiments, transitioning the pressure within the processing chamber from the first pressure to the second pressure may be done within 10 seconds.

[0204] Passivation is useful when the photoresist has boron or chlorine substituents on the surface that can destabilize the photoresist. As used herein, "passivation" means a surface treatment that results in the stabilization of the photoresist by forming a thin layer of a stable film over the photoresist or by reducing volatile moieties on the photoresist. In some embodiments, when passivation is performed with an oxygen-containing plasma, the thin layer of the stable film is an oxide, but in other embodiments, when passivation is performed with a hydrogen-containing plasma or a nitrogen-containing plasma, the volatile moieties may be removed. Also, surface smoothing may be achieved during the operation of block 414. The plasma treatment may include a transformer-coupled plasma (TCP), an inductively coupled plasma (ICP), or a capacitively coupled plasma (CCP), and may utilize devices and techniques well known to those skilled in the art. For example, the treatment may be performed at a pressure of >0.5 mTorr (e.g., 1 mTorr to 100 mTorr, etc.) and at a power level of <1000 W (e.g., <500 W). The temperature may be 30°C to 300°C (e.g., 30°C to 120°C). The flow rate may be 100 to 5000 standard cubic centimeters per minute (sccm) (e.g., about 500 sccm to) for a period of 1 to 3000 seconds (e.g., 10 seconds to 600 seconds).

[0205] In some embodiments, passivation is a treatment using an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. In some embodiments, passivation is O2, O3, CO, CO2, H2, C x H y, including plasma treatment using H2O, H2O2, SO2, NO, NO2, N2O, NH3, or a mixture thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14. The gas may be introduced into the processing chamber at a flow rate of about 100 to about 10000 sccm. The passivation may be performed at a pressure of about 5 mTorr to about 500 mTorr. The passivation may be performed with a plasma power of about 50 W to about 300 W. The passivation may be performed with a process time of about 3 seconds to about 30 seconds. In some embodiments, the passivation is a flash treatment, where the flash treatment is performed relatively quickly for about 0.5 seconds to about 4 seconds, or about 0.5 seconds to about 10 seconds.

[0206] In some embodiments, the passivation includes an O2 flash treatment in block 412 that supplies a flash gas of oxygen (O2) at 1000 sccm to 2000 sccm to the processing chamber. In certain embodiments, a high-frequency power of 100 W to 3,000 W is supplied at 13.56 MHz to convert the flash gas into plasma. A pressure of 20 mTorr to 100 mTorr is provided. Since the time during which the power is supplied is relatively short (about 0.5 seconds to about 10 seconds or about 0.5 seconds to about 10 seconds), it can be called an "O2 flash" operation. An optional purge with an inert gas may be performed after dry development and before passivation.

[0207] Operation 416 is a pattern transfer process similar to that described for operation 116 in FIG. 1 above.

[0208] Operation 418 is an optional cleaning process that may be performed to remove metal oxides and other contaminants. The cleaning process is performed after opening the processing chamber. In the cleaning process of the back and bevel edges, steam and / or plasma can be restricted to specific regions of the wafer to ensure that only the material on the back and bevel edges is removed without causing any film degradation on the front of the wafer. The photoresist film to be removed generally consists of Sn, O, and C, but the same cleaning approach can be extended to other metal oxide resist and material films. Furthermore, this approach can also be used for film stripping and photoresist modification.

[0209] For wet cleaning, the solution includes compounds such as tetramethylammonium hydroxide (TMAH), complexing amines such as ethylenediamine or diethylenetriamine, semi-water-soluble fluoride strippers, or diluted hydrofluoric acid strippers. Metal oxides can be removed using acids, and citric acid, acetic acid, octanoic acid, or other organic or inorganic acids can be used. Furthermore, hydrogen peroxide-containing acids such as a very thin (i.e., less than 0 / 1%) sulfuric acid-hydrogen peroxide mixture may be used. Any combination of the above-described wet cleaning agents may be used.

[0210] Figure 4B shows a process 420 for integrated thermal dry development and plasma dry development in a single processing chamber, according to certain disclosed embodiments. The operation of block 422 is thermal dry development. Non-limiting processes may involve the use of halides such as hydrogen halides (e.g., HBr, HCl, etc.), hydrogen and halogen gases (e.g., H2 and Cl2, H2 and Br2, etc.), boron trichloride, organic halides, acyl halides, carbonyl halides, thionyl halides, or mixtures thereof. The present disclosure is not limited to any particular theory or mechanism of operation, but the approach is understood to utilize the chemical reactivity of the EUV photoresist film with a cleaning agent (e.g., HCl, HI, HBr, and / or BCl3) to form volatile products. Such volatile products can be removed by any means (e.g., by treatment with an aqueous acid as described herein). The EUV photoresist film can be removed at an etching rate of up to 1 nm / second. The rapid removal of the EUV photoresist film by these chemical actions is applicable to chamber cleaning, backside cleaning, bevel edge cleaning, and PR development. The film can be removed using vapors at various temperatures (e.g., HCl or HBr at a temperature higher than -20°C, or BCl3 at a temperature higher than 50°C).

[0211] In the thermal dry development process, the substrate is exposed to a dry developer (e.g., a Lewis acid) in a vacuum chamber (e.g., an oven). A suitable chamber may include a vacuum line, a dry developer gas (e.g., HBr, HCl) line, and a heater for temperature control. In some embodiments, the interior of the chamber may be coated with a corrosion-resistant film (such as an organic polymer or an inorganic coating). One such coating is polytetrafluoroethylene ((PTFE), e.g., Teflon (trademark)).

[0212] The heat treatment may expose the photoresist film to a processing gas that may contain one or more halides in a process without plasma. In the thermal dry development process, the thermal dry development may be performed at a pressure of about 5 mTorr to about 760 Torr (such as about 300 mTorr). The temperature may be between about -60°C and about 120°C or between about -20°C and about 60°C (such as about -10°C). The flow rate of the processing gas in the thermal dry development process may be between about 10 sccm and about 10,000 sccm, between about 100 sccm and about 3,000 sccm (such as about 500 sccm of HBr or HCl). The thermal dry development process may expose the substrate to the processing gas for a time period of about 10 seconds to about 1 minute, depending on the photoresist film and their composition and properties. In some embodiments, the pressure is 400 to 500 mTorr for a duration of 10 to 20 seconds.

[0213] Between blocks 422 and 424, the flow path 423 may represent a change in processing conditions for transitioning from thermal dry development at block 422 to plasma dry development at block 424. For example, the flow path 423 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, enabling both high-pressure processing and low-pressure processing to be performed in the same chamber. The pressure change may be managed by a throttle valve, a dedicated pump, multiple pumps, flow control of the processing gas, or a combination of these techniques. When two or more pumps are utilized, one of the pumps may be a roughing pump and one of the pumps may be a turbo pump. An optional purge with an inert gas may be performed before, after, or during the pressure drop operation.

[0214] After thermal dry development in block 422, the operation in block 424 represents plasma dry development. The thermal dry development in block 422 and the plasma dry development in block 424 may be performed within the same processing chamber. In some embodiments, the thermal dry development in block 422 may be performed at a first pressure, and the plasma dry development in block 424 may be performed at a second pressure. For example, the second pressure may be less than or equal to the first pressure. In some examples, the first pressure is in the range between about 5 mTorr and about 760 Torr, and the second pressure is in the range between about 5 mTorr and about 200 mTorr. In some examples, the transition of the pressure within the processing chamber from the first pressure to the second pressure may be made within 10 seconds.

[0215] After thermal dry development in block 422, the operation in block 424 represents a plasma dry development process, where both operations are performed within the same processing chamber. Plasma dry development may perform a descumming and / or smoothing operation. Plasma processing includes transformer coupled plasma (TCP), inductively coupled plasma (ICP), or capacitively coupled plasma (CCP), and utilizes devices and techniques well known to those skilled in the art. Plasma dry development may be performed at a pressure greater than about 0.5 mTorr (a pressure between about 1 mTorr and about 200 mTorr or between about 5 mTorr and about 100 mTorr). Plasma dry development may apply a plasma power less than about 1000 W (a plasma power between about 1 W and about 1000 W or between about 1 W and about 500 W). Plasma dry development may be performed at a temperature between about -60 °C and about 120 °C (such as between about -20 °C and about 60 °C). The flow rate may be between 100 and 1000 standard cubic centimeters per minute (sccm) (e.g., about 500 sccm or more) for between 1 and 3000 seconds (e.g., between 10 seconds and 600 seconds).

[0216] In some embodiments, plasma dry development utilizes an inert carrier gas such as argon (Ar) or helium (He). In some embodiments, plasma dry development utilizes at least one halogen-containing gas. For example, the halogen-containing gas may include HBr, HCl, HF, HI, Br2, Cl2, F2, I2, BCl3, or a mixture thereof. The halogen-containing gas may be supplied in an inert carrier gas. In some cases, the halogen-containing gas may be utilized to remove scum during plasma dry development. In some embodiments, plasma dry development utilizes at least one carbon-containing gas. For example, the carbon-containing gas may include methane (CH4). In some embodiments, plasma dry development utilizes at least one hydrogen-containing gas. For example, the hydrogen-containing gas may include hydrogen gas (H2). In some embodiments, plasma dry development utilizes at least one nitrogen-containing gas. For example, the nitrogen-containing gas may include nitrogen gas (N2).

[0217] Under certain dry development processing conditions, a particular combination of reactants may be advantageous for plasma dry development. The combinations may include, but are not limited to, HBr and N2, HBr and H2, HBr and Cl2, HBr and HCl, HBr and BCl3, BCl3 and Cl2, BCl3 and HBr, BCl3 and CH4, CH4 and Cl2, CH4, Cl2, and N2, CH4 and HCl, or CH4 and HBr. In some examples, the above-described combinations for plasma dry development at block 424 may follow the thermal dry development of step 422 that utilizes a hydrogen halide (such as HBr).

[0218] When the flow of the halide reactant is hydrogen gas and halide gas, remote plasma / UV radiation is used to generate radicals from H2 and Cl2 and / or Br2, and the radicals of hydrogen and halide are flowed into the reaction chamber to contact the EUV photoresist on the substrate layer of the wafer. Appropriate plasma power can range from 100 W to 500 W without bias. Although these conditions are suitable for some processing reactors, it should be understood that a wider range of processing conditions may be utilized depending on the performance of the processing reactor. Although not shown in FIG. 4B, it is understood that post-development processing (such as passivation and / or curing) may be performed in the same processing chamber as thermal dry development and plasma dry development.

[0219] Operation 426 is a pattern transfer process similar to that described for operation 116 of FIG. 1 above.

[0220] Returning to FIG. 4B, after pattern transfer, an optional cleaning process 428 may be performed to remove metal oxides and other contaminants. The cleaning process is performed after opening the chamber. In the cleaning process of the back and bevel edges, the steam and / or plasma can be restricted to specific regions of the wafer to ensure that only the materials on the back and bevel edges are removed without causing any degradation of the film on the front of the wafer. The EUV photoresist film to be removed is generally composed of Sn, O, and C, but the same cleaning approach can be extended to other metal oxide resist and material films. Furthermore, this approach can also be used for film stripping and photoresist modification.

[0221] For wet cleaning, the solution includes a compound such as tetramethylammonium hydroxide (TMAH), a complexing amine such as ethylenediamine or diethylenetriamine, a semi-water-soluble fluoride etchant, or a diluted hydrofluoric acid etchant. Metal oxides can be removed using an acid, such as citric acid, acetic acid, octanoic acid, or other organic or inorganic acids. Additionally, a hydrogen peroxide-containing acid, such as a very thin (i.e., less than 0 / 1%) sulfuric acid-hydrogen peroxide mixture, may be used. Any combination of the above-described wet cleaning agents may be used.

[0222] Figure 4C shows a process 430 for integrated dry development and curing in a single processing chamber, according to a particular disclosed embodiment. The operation of block 432 is thermal dry development. The operation at block 432 is similar to the operation described at block 422 in Figure 4B.

[0223] Between blocks 432 and 434, a flow path 433 may represent a change in process conditions for transitioning from thermal dry development at block 432 to plasma dry development and curing at block 434. Specifically, the flow path 433 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, enabling both high-pressure and low-pressure processes to be performed in the same chamber. The pressure change may be managed by a throttle valve, a dedicated pump, a plurality of pumps, flow control of the process gas, or a combination of these techniques. If more than one pump is utilized, one of the pumps may be a roughing pump and one of the pumps may be a turbo pump. An optional purge with an inert gas may be performed before, after, or during the pressure drop operation.

[0224] After thermal dry development in block 432, the operation in block 434 represents plasma dry development and / or curing. In some cases, the operation in block 434 is only the curing process. In some other cases, the operation in block 434 is both plasma dry development and the curing process. The thermal dry development in block 432 and the plasma dry development and / or curing in block 434 may be performed in the same processing chamber. In some embodiments, the thermal dry development in block 432 may be performed at a first pressure, and the plasma dry development and curing in block 434 may be performed at a second pressure. For example, the second pressure may be less than or equal to the first pressure. In some examples, the first pressure ranges between about 5 mTorr and about 760 Torr, and the second pressure ranges between about 5 mTorr and about 200 mTorr. In some examples, the transition of the pressure in the processing chamber from the first pressure to the second pressure may be made within 10 seconds.

[0225] The mode of plasma dry development in block 434 is the same as that described in block 424 of FIG. 4B. The mode of curing in block 434 is described below. Post-development processing such as curing may be performed in the same processing chamber as the thermal dry development in block 432.

[0226] For certain applications, it is desirable to cure the photoresist. As used herein, "curing" means treating the surface and interior of the photoresist to concentrate the material by processes such as cross-linking and / or cleavage of the metal-carbon bonds in the photoresist. This can function to increase the density of the photoresist material. In some embodiments, curing may be achieved by treatment with a plasma of an inert gas. In one example, curing by treatment with plasma may include plasma ignition to generate reactive species (e.g., ions and / or radicals) of argon, nitrogen, xenon, or helium. In some embodiments, curing may be achieved by flash treatment (such as O2 flash treatment), which can perform both passivation and curing. In certain embodiments, the pressure may be from about 5 mTorr to about 500 mTorr, and the plasma power (e.g., TCP power) may be from about 50 W to about 300 W. The gas flow rate may be from about 100 sccm to about 1000 sccm for a process time of from about 5 mTorr to about 500 mTorr.

[0227] In some alternative embodiments, curing may be achieved by exposure to UV light. For example, exposure to UV light for curing may include exposure from one or more UV lamps at a power of from about 10 W to about 1000 W and a pressure of from about 5 mTorr to about 760 Torr. In some embodiments, curing may be achieved by a combination of exposure to a plasma of an inert gas and exposure to UV light.

[0228] In some embodiments, curing may be performed during or after plasma dry development. In some embodiments, curing may be performed without plasma dry development.

[0229] Operation 436 is a pattern transfer process similar to that described for operation 116 of FIG. 1 above.

[0230] Operation 438 is an optional cleaning process. The manner of the cleaning process at block 438 is the same as that described at block 428 in FIG. 4B.

[0231] FIG. 4D shows a process 440 for integrated thermal dry development, plasma dry development, and passivation in a single processing chamber according to a particular disclosed embodiment. The operation of block 442 is thermal dry development. The operation at block 442 is the same as the operation described at block 422 in FIG. 4B.

[0232] Between blocks 442 and 444, flow path 443 may represent a change in processing conditions for transitioning from thermal dry development at block 442 to plasma dry development and passivation at block 444. In particular, flow path 443 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, enabling both high-pressure processing and low-pressure processing to be performed in the same chamber. The pressure change may be managed by a throttle valve, a dedicated pump, multiple pumps, flow control of the processing gas, or a combination of these techniques. If more than one pump is utilized, one of the pumps may be a roughing pump and one of the pumps may be a turbo pump. An optional purge with an inert gas may be performed before, after, or during the pressure drop operation.

[0233] After thermal dry development in block 442, the operations in block 444 represent plasma dry development and passivation. The thermal dry development in block 442 and the plasma dry development and passivation in block 444 may be performed within the same processing chamber. In some embodiments, the thermal dry development in block 442 may be performed at a first pressure, and the plasma dry development and passivation in block 444 may be performed at a second pressure. For example, the second pressure may be less than or equal to the first pressure. In some examples, the first pressure is in the range between about 5 mTorr and about 760 Torr, and the second pressure is in the range between about 5 mTorr and about 200 mTorr. In some examples, transitioning the pressure within the processing chamber from the first pressure to the second pressure may be done within 10 seconds.

[0234] The manner of plasma dry development in block 444 is similar to that described for block 424 in FIG. 4B. The manner of passivation in block 444 is similar to that described for block 414 in FIG. 4A. In some embodiments, the passivation is a plasma flash treatment such as an O2 plasma flash treatment. Post-development processing such as passivation may be performed within the same processing chamber as the thermal dry development in block 442. In some embodiments, the passivation may be performed during or after the plasma dry development.

[0235] Operation 446 is a pattern transfer process similar to that described for operation 116 in FIG. 1 above.

[0236] Operation 448 is an optional cleaning process. The manner of the cleaning process in block 448 is similar to that described for block 428 in FIG. 4B.

[0237] FIG. 4E shows an alternative process 450 for dry development, passivation, and curing all integrated into a single processing chamber according to a particular disclosed embodiment. The operation in block 452 represents the thermal dry development described above for block ......................................................

[0238] Between blocks 452 and 454, flow path 453 represents a pressure change procedure performed within the processing chamber. As described above for flow path 453, the required pressure drop may be achieved within the processing chamber, enabling both high-pressure and low-pressure processing to be performed in the same chamber. The pressure change may be managed by a throttle valve, a dedicated pump, multiple pumps, flow control of the processing gas, or a combination of these techniques. When two or more pumps are utilized, one of the pumps may be a roughing pump and one of the pumps may be a turbo pump.

[0239] After thermal dry development at block 452, the operations at block 454 represent plasma dry development, passivation, and curing processes that can all be performed within one (the same) processing chamber.

[0240] Plasma dry development and passivation are the same as those described above with reference to FIGS. 4A, 4B, 4C, and 4D. The mode of curing was described above with reference to FIG. 4C.

[0241] Returning to FIG. 4E, an optional purge with an inert gas may be performed during operation 453, between operations 454 and 456, and between plasma dry development and passivation, and / or between plasma dry development and curing.

[0242] Operation 456 is a pattern transfer process similar to that described for operation 116 in FIG. 1 above.

[0243] After operation 456, an optional cleaning process 458 similar to the operation described for block 428 in FIG. 4B above may be performed.

[0244] FIGS. 5A - 5E are schematic cross-sectional views showing various processing stages including thermal dry development, plasma dry development, and passivation according to a particular disclosed embodiment. The processing stages may be performed in a single processing chamber.

[0245] In FIG. 5A, a photoresist 510 (such as a metal-containing photoresist) is provided on a semiconductor substrate 501. The photoresist 510 may be photopatterned such that the photoresist 510 includes an exposed region 503 (or a more exposed region) and an unexposed region 505 (or a less exposed region). As shown in FIG. 5A, metal / metal oxide particles or clusters 507 may occupy the unexposed region 505. In some embodiments, the photopatterned photoresist 510 may be provided to a processing chamber after EUV exposure in an EUV scanner.

[0246] In FIG. 5B, the photoresist 510 is developed using a thermal dry development process in a processing chamber. As the thermal dry development proceeds, the metal / metal oxide clusters 507 become more concentrated. The metal / metal oxide clusters 507 are generally difficult to remove. Thermal dry development may selectively remove the unexposed region 505 rather than the exposed region 503. Bulk removal of the unexposed region 505 may be performed under thermal dry development. Thermal dry development may be selective for the removal of organic materials. After bulk removal of the unexposed region 505, the metal / metal oxide clusters 507 may remain as a scum on the surface of the semiconductor substrate 501. In some embodiments, thermal dry development may be performed by exposure to a halide (such as hydrogen halide). As an example, the hydrogen halide may include HBr. In some embodiments, thermal dry development may be performed at a first pressure in a processing chamber, where the first pressure may be between about 5 mTorr and about 760 Torr. In some embodiments, thermal dry development may be performed at a temperature between about -20°C and about 60°C, and the flow rate of the processing gas may be between about 100 sccm and about 3000 sccm.

[0247] In FIG. 5C, the photoresist 510 is developed using plasma dry development in a processing chamber. As the plasma dry development proceeds, the clusters 507 of metal / metal oxide are removed. Further, the plasma dry development can remove or substantially remove the remainder of the non-exposed region 505. In some embodiments, the plasma dry development can utilize a plasma of an inert gas species (such as He or Ar). In some embodiments, the plasma dry development can utilize a plasma of a halogen-containing species. For example, the halogen-containing gas can include HBr, HCl, HF, HI, Br2, Cl2, F2, I2, BCl3, or a mixture thereof. The halogen-containing gas can be supplied in an inert carrier gas. In some embodiments, the plasma dry development can use a combination of a plasma of an inert gas species and a plasma of a halogen-containing gas. In some embodiments, the plasma dry development includes cyclic plasma dry development. In one example, the cyclic plasma dry development can alternately expose to an inert gas plasma and a halogen-containing gas plasma. In some embodiments, the plasma dry development includes continuous plasma dry development. The continuous plasma dry development can be performed at variable power, at constant power and pulse bias, or at variable power and pulse bias. In some embodiments, the plasma dry development is utilized to remove scum from the surface of the semiconductor substrate 501. In some embodiments, a specific combination of reactants can be used in the plasma dry development. The combinations can include, but are not limited to, HBr and N2, HBr and H2, HBr and Cl2, HBr and HCl, HBr and BCl3, BCl3 and Cl2, BCl3 and HBr, BCl3 and CH4, CH4 and Cl2, CH4, Cl2, and N2, CH4 and HCl, or CH4 and HBr. In some embodiments, the plasma dry development can be performed at a second pressure in the processing chamber, where the second pressure can be between about 5 mTorr and about 200 mTorr.In some embodiments, plasma dry development may be performed at a temperature between about -20°C and about 60°C, the flow rate of the processing gas may be between about 100 sccm and about 3000 sccm, the TCP power may be between about 1 W and about 500 W, and the bias voltage may be between about 1 V and about 300 V.

[0248] In FIG. 5D, the photoresist 510 after plasma dry development is shown. The metal / metal oxide clusters 507 are removed, and the unexposed regions 505 of the photoresist 510 are removed. In some embodiments, a critical dimension (CD) loss 509 occurs as a result of plasma dry development. However, due to the directionality of plasma dry development and other conditions associated with plasma dry development, the metal / metal oxide clusters 507 can be removed with minimal CD loss 509. Additionally, plasma dry development may be utilized to improve line width roughness (LWR) performance.

[0249] In FIG. 5E, the passivated photoresist 510 is shown. Passivation may be performed in the same processing chamber as thermal dry development and plasma dry development. Passivation may be performed at the same pressure as plasma dry development. In some embodiments, passivation may form a passivation layer 511 on the exposed surface of the photoresist 510. For example, the passivation layer 511 may include oxides and / or nitrides and / or carbon. In some embodiments, passivation is a treatment using an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. For example, passivation is O2, O3, CO, CO2, H2, C x H y, H2O, H2O2, SO2, NO, NO2, N2O, NH3, or a plasma treatment using a mixture thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14. In one example, passivation includes an O2 flash treatment, where the photoresist 510 is exposed to O2 plasma at a relatively fast timing (such as about 0.5 seconds to about 4 seconds). Passivation can provide in-situ surface stabilization to prevent gas evolution from the photoresist 510. Passivation may additionally or alternatively perform curing of the photoresist 510. Passivation may additionally or alternatively provide surface smoothing of the photoresist 510.

[0250] The above description is merely illustrative in nature and is not intended to limit the present disclosure, its applications, or its uses. The broad teachings of the present disclosure can be implemented in various forms. Accordingly, while the present disclosure includes specific examples, other variations will become apparent upon study of the drawings, the specification, and the following claims, and the true scope of the present disclosure is not limited to those examples. It should be understood that one or more steps included in the method may be performed in a different order (or simultaneously) without modifying the principles of the present disclosure. Further, each embodiment is described as having certain features, but any one or more of the features described with respect to any embodiment of the present disclosure can be implemented in and / or combined with any of the other embodiments, even if the combination is not explicitly described. In other words, the above embodiments are not mutually exclusive, and it is within the scope of the present disclosure to replace one or more embodiments with each other.

[0251] Apparatus The apparatus of the present disclosure is configured for dry development of photoresist and, in some cases, also for post-development processing of a photoresist mask. The apparatus may be configured for other processing operations such as deposition, bevel and backside cleaning, post-application bake, EUV scan, post-exposure bake, development, etching, and other operations. In some embodiments, the apparatus is configured to perform a plurality of dry operations. In some embodiments, the apparatus is configured to perform a combination of wet and dry operations. The apparatus may comprise a single wafer chamber or multiple stations within the same processing chamber. In multiple stations within the same processing chamber, various processing operations such as those described in the present disclosure may be performed at different stations within the same processing chamber. In some embodiments, the processing chamber for post-development processing of the present disclosure may be performed in the same chamber as development, in the same chamber as pattern transfer etching, or in the same chamber as both development and pattern transfer etching.

[0252] An apparatus configured for dry development and, in some cases, configured for dry development and post-development processing includes a processing chamber with a substrate support. The apparatus may include at least one reaction gas source in fluid communication with the processing chamber. The apparatus may include one or more gas lines for the supply of one or more gas species. In some embodiments, the one or more reaction gas species may include organic gas species, organometallic gas species, metal-containing gas species, or combinations thereof. In some embodiments, the one or more reaction gas species may include oxygen-containing gases, carbon-containing gases, hydrogen-containing gases, nitrogen-containing gases, halogen-containing gases, or combinations thereof. The one or more reaction gas species may be supplied to the processing chamber via one or more gas lines for developing a photoresist and / or for processing a photoresist mask after development. The apparatus may include one or more heating elements for temperature control. Such heating elements may be provided within the processing chamber and / or within the substrate support. Alternatively, such heating elements may be provided outside the processing chamber. In some examples, the apparatus may include a plasma source for generating plasma during development and / or during processing of the photoresist mask after development. In some examples, one or more reactive species may selectively deposit a protective film on the photoresist mask after development. The apparatus may further include one or more sensors for sensing the number of particles, the number of wafers, the thickness, or other parameters for triggering an endpoint of the post-development processing.

[0253] FIG. 6 is a schematic diagram showing an example of a processing station for maintaining an environment suitable for performing a photoresist developing operation and a photoresist processing operation according to some embodiments. For simplicity, processing station 600 is illustrated as a stand-alone processing station having a processing chamber body 602 for maintaining a low-pressure environment. However, it can be seen that a plurality of processing stations 600 may be included in a common processing tool environment. Further, in some embodiments, one or more hardware parameters of processing station 600 (such as parameters described in detail below) may be programmatically adjusted by one or more computer controllers.

[0254] A plurality of processing stations 600 may be provided within a common low-pressure processing tool environment. For example, FIG. 7 illustrates an example of a multi-station processing tool 700. In some embodiments, one or more hardware parameters of processing tool 700 (such as parameters described in detail below) may be programmatically adjusted by one or more computer controllers 750.

[0255] The processing station may be configured as a module within a cluster tool. FIG. 9 is a diagram showing a semiconductor processing cluster tool architecture including a vacuum integrated deposition module and a patterning module suitable for the implementation of the embodiments described herein. Such a cluster processing tool architecture has been described above with reference to FIGS. 6 and 7 and can further include a resist deposition, a resist exposure (EUV scanner), a resist development, a resist repair, and an etching module, as will be further described below.

[0256] Returning to FIG. 6, the processing station 600 is in fluid communication with a reactant supply system 601 for supplying a processing gas to the showerhead 606. The reactant supply system 601 optionally includes a mixing vessel 604 for mixing and / or conditioning the processing gas for supply to the showerhead 606. One or more mixing vessel inlet valves 620 may control the introduction of the processing gas into the mixing vessel 604. When plasma exposure is utilized, the plasma may be supplied to the showerhead 606 or generated at the processing station 600. As described above, in at least some embodiments, non-plasma thermal exposure is preferred.

[0257] FIG. 6 includes an optional vaporization point 603 for vaporizing a liquid reactant supplied to the mixing vessel 604. In some embodiments, upstream of the vaporization point 603, a liquid flow controller (LFC) may be provided to control the mass flow rate of the liquid for vaporization and supply to the processing station 600. For example, the LFC may include a thermal mass flow meter (MFM) disposed downstream of the LFC. The plunger valve of the LFC may then be adjusted in response to a feedback control signal provided by a proportional integral derivative (PID) controller in electrical communication with the MFM.

[0258] The showerhead 606 distributes the processing gas to the substrate 612. In the embodiment shown in FIG. 6, the substrate 612 is disposed below the showerhead 606 and is illustrated on the pedestal 608. The showerhead 606 may have any suitable shape and may have any suitable number and arrangement of ports for distributing the processing gas to the substrate 612.

[0259] In some embodiments, the pedestal 608 may be moved up and down to expose the substrate 612 in the space 607 between the substrate 612 and the showerhead 606. It can be seen that in some embodiments, the height of the pedestal may be programmatically adjusted by a suitable computer controller. In some embodiments, the showerhead 606 may have a plurality of plenum spaces with a plurality of temperature control sections.

[0260] In some embodiments, the pedestal 608 may be temperature-controlled using a heater 610. In some embodiments, the pedestal 608 may be heated to a temperature higher than -20°C and up to 300°C (e.g., heated up to 50°C to 280°C (such as about 100°C to 240°C, etc.)) during development or post-development processing as described in the disclosed embodiments. In some embodiments, the heater 610 of the pedestal 608 may include a plurality of independently controllable temperature control zones.

[0261] Furthermore, in some embodiments, the pressure control of the processing station 600 may be provided by a butterfly valve 618. As shown in the embodiment of FIG. 6, the butterfly valve 618 throttles the vacuum provided by a downstream vacuum pump (not shown). However, in some embodiments, the pressure control of the processing station 600 may be adjusted by changing the flow rate of one or more gases introduced into the processing station 600.

[0262] In some embodiments, the position of the showerhead 606 may be adjusted relative to the pedestal 608 to change the space between the substrate 612 and the showerhead 606. Furthermore, it can be seen that the vertical positions of the pedestal 608 and / or the showerhead 606 may be changed by any suitable mechanism within the scope of the present disclosure. In some embodiments, the pedestal 608 may include a rotation axis for rotating the orientation of the substrate 612. It can be seen that in some embodiments, one or more of these examples of adjustments may be programmatically executed by one or more suitable computer controllers.

[0263] When plasma can be utilized, for example, during descumming, developing, processing, deposition, or planarization operations, the showerhead 606 and the pedestal 608 are electrically communicated with a radio frequency (RF) power source 614 and a matching circuit network 616 to supply power to the plasma. In some embodiments, the plasma energy may be controlled by controlling one or more of the processing station pressure, gas concentration, RF source power, RF source frequency, and plasma power pulse timing. For example, the RF power source 614 and the matching circuit network 616 may be operated at any suitable power to form a plasma having radical species of a desired composition. An example of suitable power is power up to about 1000 W.

[0264] In some embodiments, instructions for a computer controller (not shown) may be provided via input / output control (IOC) sequencing instructions. In one example, instructions for setting the conditions of a processing stage may be included in the corresponding recipe stage of a processing recipe. In some examples, the processing recipe stages may be arranged sequentially, such that all instructions for a processing stage are executed simultaneously with that processing stage. In some embodiments, instructions for setting one or more reactor parameters may be included in the recipe stage. For example, the recipe stage may include instructions for setting the flow rate of an etching gas (such as hydrogen halide) and time delay instructions for the recipe stage. In some embodiments, the controller may comprise any of the features described hereinafter with respect to the controller 750 of FIG. 7.

[0265] The processing chamber may further comprise a UV exposure module (not shown).

[0266] In some embodiments, the processing chamber may further comprise a photoresist thickness sensor module (not shown). The photoresist thickness sensor module may be a spectrometer system including a lamp source, an optical cable, and an optical reflectometer operating within a spectral range of about 200 to about 900 nm. The reflectometer may be useful for monitoring the thickness of the photoresist during dry development to measure the wafer reflectivity over time in situ.

[0267] As described above, one or more processing stations may be included in the multi-station processing tool. FIG. 7 is a schematic diagram showing an example of a multi-station processing tool 700 including an inlet load lock 702 and an outlet load lock 704, and one or both of the load locks may include a remote plasma source. A robot 706 under atmospheric pressure is configured to move a wafer from a cassette loaded through a pod 708 into the inlet load lock 702 through an atmospheric port 710. The wafer is placed on a pedestal 712 in the inlet load lock 702 by the robot 706, the atmospheric port 710 is closed, and the load lock is pumped out. If the inlet load lock 702 includes a remote plasma source, the wafer may be subjected to remote plasma processing to process the substrate surface in the load lock before being introduced into the processing chamber 714. Further, the wafer may be heated in the inlet load lock 702, for example, to remove moisture and adsorbed gas. Next, a chamber transfer port 716 to the processing chamber 714 is opened, and another robot (not shown) places the wafer into the reactor for processing and positions it on the pedestal of the first station shown in the reactor. Although the embodiment shown in FIG. 7 includes a load lock, it can be seen that in some embodiments, the wafer may be directly placed into the processing station.

[0268] The process chamber 714 of the figure, in the embodiment shown in FIG. 7, comprises four process stations numbered from 1 to 4. Each station has a heated pedestal (shown as 718 for station 1) and a gas line inlet. It can be seen that in some embodiments, each process station may have different purposes or multiple purposes. For example, in some embodiments, one process station may be switchable between a development mode and an etching process mode. Additionally or alternatively, in some embodiments, the process chamber 714 may comprise one or more matched pairs of development stations and etching process stations. Although the process chamber 714 of the figure comprises four stations, it can be seen that a process chamber according to the present disclosure may have any suitable number of stations. For example, in some embodiments, the process chamber may have 5 or more stations, and in other embodiments, the process chamber may have 3 or fewer stations.

[0269] FIG. 7 shows an embodiment of a wafer handling system 790 for moving wafers within the process chamber 714. In some embodiments, the wafer handling system 790 can move wafers between various process stations and / or between a process station and a load lock. It can be seen that any suitable wafer handling system may be used. Non-limiting examples include a wafer carousel and a wafer handler robot. Also, FIG. 7 shows an embodiment of a controller 750 (e.g., a system controller) used to control the process conditions and the state of the hardware of the processing tool 700. The controller 750 may comprise one or more memory devices 756, one or more mass storage devices 754, and one or more processors 752. The processor 752 may comprise a CPU or a computer, analog and / or digital input / output connections, a stepper motor controller board, etc.

[0270] In some embodiments, the controller 750 controls all operations of the processing tool 700. The controller 750 executes system control software 758 that is stored in the mass storage device 754, loaded into the memory device 756, and executed by the processor 752. Alternatively, the control logic may be hard-coded in the controller 750. For these purposes, application specific integrated circuits, programmable logic devices (e.g., field programmable gate arrays or FPGAs), etc. may be used. Hereinafter, when "software" or "code" is utilized, functionally equivalent hard-coded logic may be used instead. The system control software 758 may include instructions for controlling timing, gas mixing, gas flow rate, pressure of the chamber and / or station, temperature of the chamber and / or station, wafer temperature, target power level, RF power level, position of the substrate pedestal, chuck, and / or susceptor, and other parameters of the specific process executed by the processing tool 700. The system control software 758 may be configured in any suitable manner. For example, various processing tool component subroutines or control objects may be written to control the operations of the processing tool components used to execute the processes of various processing tools. The system control software 758 may be coded in any suitable computer-readable program language.

[0271] In some embodiments, the system control software 758 may include input / output control (IOC) sequence instructions for controlling the various parameters described above. Other computer software and / or programs stored in the mass storage device 754 and / or memory device 756 associated with the controller 750 may be used in some embodiments. Examples of programs or program sections for this purpose include a substrate positioning program, a process gas control program, a pressure control program, a heater control program, and a plasma control program.

[0272] The substrate positioning program may include program code for a processing tool component used to load a substrate onto the pedestal 718 and to control the spacing between the substrate and other components of the processing tool 700.

[0273] The process gas control program may include code for controlling the process gas composition and flow rate, and optionally for flowing gas into one or more process stations prior to deposition to stabilize the pressure within the process station. The pressure control program may include code for controlling the pressure within the process station, for example, by adjusting the throttle valve of the exhaust system of the process station, the gas flow rate to the process station, and the like.

[0274] The heater control program may include code for controlling the current to a heating unit used to heat the substrate. Alternatively, the heater control program may control the supply of a heat transfer gas (such as helium) to the substrate.

[0275] The plasma control program may include code for setting the RF power level applied to a processing electrode within one or more processing stations, according to the embodiments of the present specification.

[0276] The pressure control program may include code for maintaining the pressure within the reaction chamber, according to the embodiments of the present specification.

[0277] In some embodiments, there may be a user interface associated with the controller 750. The user interface may include a display screen (a graphical software display of the apparatus and / or processing conditions), and user input devices such as a pointing device, keyboard, touch screen, microphone, and the like.

[0278] In some embodiments, the parameters adjusted by the controller 750 may relate to processing conditions. Non-limiting examples include the composition and flow rate of the processing gas, temperature, pressure, plasma conditions (such as RF bias power level), and the like. These parameters may be provided to the user in the form of a recipe and may be input using a user interface.

[0279] Signals for monitoring the process may be provided from various process tool sensors to the analog and / or digital input connections of the controller 750. Signals for controlling the process may be output at the analog and digital output connections of the process tool 700. Non-limiting examples of process tool sensors that may be monitored include mass flow controllers, pressure sensors (such as pressure gauges), thermocouples, and the like. Appropriately programmed feedback algorithms and control algorithms may be used with the data from these sensors to maintain the processing conditions.

[0280] The controller 750 may provide program instructions for performing the deposition process described above. The program instructions may control various process parameters such as DC power level, RF bias power level, pressure, temperature, and the like. The instructions may control the parameters to operate the development and / or etching processes according to the various embodiments described herein.

[0281] The controller 750 typically includes one or more memory devices and one or more processors configured to execute instructions such that the apparatus executes the method according to the disclosed embodiments. A machine-readable medium containing instructions for controlling the processing operations according to the disclosed embodiments may be connected to the controller 750.

[0282] In some embodiments, the controller 750 is part of a system, which may be part of the examples described above. Such a system may include a semiconductor processing apparatus, such as one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (e.g., wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling the operation of the system before, during, and after processing of a semiconductor wafer or substrate. The electronics may be referred to as a “controller” and may control various components or sub-parts of the system. The controller 750 may be programmed to control any of the processes disclosed herein, depending on the processing conditions and / or the type of system, including the supply of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid supply settings, position and motion settings, and wafer transfer into and out of a load lock connected or coupled to a tool and other transfer tools and / or a particular system.

[0283] Generally, the controller 750 may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuits may include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions may be communicated to the controller 750 in the form of various individual settings (or program files) and may be operation parameters for performing a specific process on or for a semiconductor wafer or instructions that define operation parameters for the system. The operation parameters may, in some embodiments, be part of a recipe defined by a process engineer to achieve one or more processing steps during the processing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of the wafer.

[0284] In some embodiments, the controller 750 may be integrated with the system, connected to the system, networked with the system in some other way, or be part of a computer coupled to the system in combinations thereof, and may also be connected to such a computer. For example, the controller 750 may be within the “cloud” or may be all or part of a fab host computer system that enables remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of the manufacturing operation, examine the history of past manufacturing operations, or examine trends or performance metrics from multiple manufacturing operations, to change the parameters of the current process, set process steps according to the current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide a process recipe to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, and the parameters and / or settings are communicated from the remote computer to the system. In some examples, the controller 750 receives instructions in the form of data, and the instructions specify parameters for each of the process steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool that the controller 750 is configured to interface with or control. Thus, as described above, the controller 750 may be distributed, such as by comprising one or more separate controllers networked together to operate towards a common purpose (such as the processes and controls described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber that communicate with one or more remotely located (such as at the platform level or as part of a remote computer) integrated circuits that cooperate to control the processing in the chamber.

[0285] Although not limited, examples of systems can include a plasma etching chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etching chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an ALD chamber or module, an atomic layer etching (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, an EUV lithography chamber (scanner) or module, a developing chamber or module, and any other semiconductor processing system that may be related to or utilized in the processing and / or manufacturing of semiconductor wafers.

[0286] As described above, depending on one or more processing steps performed by the tool, the controller 750 may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or a tool used for transporting the wafer container to or from a tool location and / or load port within a semiconductor manufacturing facility.

[0287] In certain embodiments, an ICP reactor that may be suitable for etching operations suitable for implementation of some embodiments is described herein. Although an ICP reactor is described herein, it should be understood that in some embodiments, a capacitively coupled plasma reactor may be used.

[0288] FIG. 8 is a schematic cross-sectional view showing an inductively coupled plasma apparatus 800 suitable for implementing specific embodiments or aspects of embodiments, such as dry development, post-development processing (e.g., passivation and curing), and / or etching. In other embodiments, other tools or tool types having the function of performing the dry development, post-development processing, and / or etching processes described herein may be used for implementation.

[0289] The inductively coupled plasma apparatus 800 includes an overall processing chamber 824 structurally defined by a chamber wall 801 and a window 811. The chamber wall 801 may be made of stainless steel, aluminum, or plastic. The window 811 may be made of quartz or other dielectric materials. An optional internal plasma grid 850 divides the overall processing chamber into an upper sub-chamber 802 and a lower sub-chamber 803. In most embodiments, by removing the plasma grid 850, the chamber spaces formed in the sub-chambers 802 and 803 can be utilized. A chuck 817 is disposed near the bottom inner surface within the lower sub-chamber 803. The chuck 817 is configured to receive and hold a semiconductor wafer 819 on which an etching process and a deposition process are performed. The chuck 817 can be an electrostatic chuck for supporting the wafer 819 in the presence of the wafer. In some embodiments, an edge ring (not shown) surrounds the chuck 817 and has an upper surface that is substantially coplanar with the upper surface of the wafer 819 when the wafer is present on the chuck 817. The chuck 817 also includes electrostatic electrodes for chucking and de-chucking the wafer 819. A filter and a DC clamp power supply (not shown) may be provided therefor. Other control systems for lifting the wafer 819 from the chuck 817 may also be provided. The chuck 817 can be charged using an RF power supply 823. The RF power supply 823 is connected to a matching circuit 821 through a connection 827. The matching circuit 821 is connected to the chuck 817 through a connection 825. Thus, the RF power supply 823 is connected to the chuck 817. In various embodiments, the bias power of the electrostatic chuck may be set to about 50V or to different bias powers according to the processes performed in accordance with the disclosed embodiments. For example, the bias power may be from about 20V to about 100V, or from about 30V to about 150V.

[0290] Elements for plasma generation include a coil 833 disposed above the window 811. In some embodiments, the coil is not utilized in the disclosed embodiments. The coil 833 is manufactured from a conductive material and includes at least one complete winding. The example of the coil 833 shown in FIG. 8 includes three windings. The cross-section of the coil 833 is indicated by symbols, where the "X" coil rotates and extends from the front to the back of the paper surface, and the "●" coil rotates and extends from the back to the front of the paper surface. Elements for plasma generation also include an RF power source 841 configured to supply RF power to the coil 833. Generally, the RF power source 841 is connected to a matching circuit 839 through a connection 845. The matching circuit 839 is connected to the coil 833 through a connection 843. In this way, the RF power source 841 is connected to the coil 833. An optional Faraday shield 849 is disposed between the coil 833 and the window 811. The Faraday shield 849 may be maintained in a spaced relationship with respect to the coil 833. In some embodiments, the Faraday shield 849 is disposed directly above the window 811. In some embodiments, the Faraday shield 849 is between the window 811 and the chuck 817. In some embodiments, the Faraday shield 849 is not maintained in a spaced relationship with respect to the coil 833. For example, the Faraday shield 849 may be directly below the window 811 without a gap. The coil 833, the Faraday shield 849, and the window 811 are each configured to be substantially horizontal with respect to each other. The Faraday shield 849 can prevent metal or other species from depositing on the window 811 of the processing chamber 824.

[0291] The processing gas may be flowed into the processing chamber through one or more main gas inlets 860 disposed within the upper subchamber 802 and / or through one or more side gas inlets 870. Similarly, although not shown, similar gas inlets may be used to supply the processing gas to the capacitively coupled plasma processing chamber. A vacuum pump (e.g., a one- or two-stage mechanical dry pump and / or a turbomolecular pump) 840 may be used to draw the processing gas out of the processing chamber 824 and to maintain the pressure within the processing chamber 824. For example, the vacuum pump may be used to evacuate the lower subchamber 803 during a purge operation. A valve-controlled conduit may be used to fluidly connect the vacuum pump to the processing chamber 824 to selectively control the application of the vacuum environment provided by the vacuum pump. This may be done using a closed-loop controlled flow restrictor such as a throttle valve (not shown) or a pendulum valve (not shown) during the operation of the plasma processing. Similarly, a vacuum pump and a valve-controlled fluid connection to the capacitively coupled plasma processing chamber may be used. The wide range of pressures regulated within the processing chamber for integrated dry development and etching may be achieved by a variable speed vacuum system, a throttle valve, or by adjusting the flow rate of the processing gas, or by using two pressure regulating systems.

[0292] During operation of the apparatus 800, one or more process gases may be supplied through the gas inlets 860 and / or 870. In certain embodiments, the process gas may be supplied only through the main gas inlet 860 or only through the side gas inlet 870. In some cases, the gas inlets shown in the figures may be replaced, for example, with more complex gas inlets, one or more showerheads. The Faraday shield 849 and / or the optional grid 850 may include internal channels and holes that allow for the supply of the process gas to the processing chamber 824. One or both of the Faraday shield 849 and the optional grid 850 may function as a showerhead for the supply of the process gas. In some embodiments, a liquid vaporization / supply system may be disposed upstream of the processing chamber 824 such that a liquid reactant or precursor is vaporized and the vaporized reactant or precursor is introduced into the processing chamber 824 via the gas inlets 860 and / or 870.

[0293] RF power is supplied from the RF power source 841 to the coil 833, causing an RF current to flow through the coil 833. The RF current flowing through the coil 833 generates an electromagnetic field around the coil 833. The electromagnetic field generates an induced current within the upper subchamber 802. The physical and chemical interactions between the various ions and radicals generated and the wafer 819 etch the features of the wafer 819 and selectively deposit a layer on the wafer 819.

[0294] When the plasma grid 850 is utilized such that both the upper subchamber 802 and the lower subchamber 803 are present, the induced current acts on the gas present in the upper subchamber 802 to generate an electron-ion plasma within the upper subchamber 802. The optional internal plasma grid 850 limits the amount of hot electrons within the lower subchamber 803. In some embodiments, the apparatus 800 is designed and operated such that the plasma present in the lower subchamber 803 becomes an ion-ion plasma.

[0295] The upper electron-ion plasma and the lower ion-ion plasma both contain positive and negative ions, but the ion-ion plasma has a higher ratio of negative ions to positive ions. Volatile etching by-products and / or deposition by-products may be removed from the lower sub-chamber 803 through port 822. The chuck 817 disclosed herein may be operated at a high temperature in the range of about 10°C to about 250°C. The temperature depends on the processing operation and the individual recipe.

[0296] When installed in a clean room or manufacturing facility, the apparatus 800 may be connected to a facility (not shown). The facility includes piping that provides process gas, vacuum, temperature control, and environmental particle control. These facilities are connected to the apparatus 800 when installed in the manufacturing facility of interest. Further, the apparatus 800 may be connected to a transfer chamber that enables the transfer of semiconductor wafers in and out of the apparatus 800 by robotics using typical automation.

[0297] In some embodiments, a controller 830 (which may include one or more physical or logical controllers) controls some or all of the operation of the processing chamber 824. The controller 830 may include one or more memory devices and one or more processors. In some embodiments, the apparatus 800 includes a switching system for controlling flow rate and duration when the disclosed embodiments are executed. In some embodiments, the apparatus 800 may have a switching time of up to about 500 ms or up to about 750 ms. The switching time may depend on the flow chemistry, the selected recipe, the reactor architecture, and other factors.

[0298] In some embodiments, the controller 830 is part of a system, and the system may be part of the examples described above. Various aspects of the controller 830 have been described above.

[0299] EUVL patterning may be performed using any suitable tool (often referred to as a scanner). The EUVL patterning tool may be a stand-alone apparatus into which a substrate is loaded and unloaded for the deposition and etching described herein. Alternatively, as described below, the EUVL patterning tool may be a module on a large multi-component tool.

[0300] FIG. 9 shows a semiconductor processing cluster tool architecture 900 comprising a vacuum integrated deposition module, a patterning module, and a processing module, connected to a vacuum transfer module, suitable for implementation of the processes described herein. The arrangement of transfer modules that "transfer" wafers between multiple storage facilities and processing modules is sometimes referred to as a "cluster tool architecture" system. The deposition module, patterning module, and processing module are vacuum integrated according to the requirements of a particular process. Other modules, such as for etching, may be provided in the cluster.

[0301] A vacuum transfer module (VTM) 938 is connected to four processing modules 920a-920d, which may be individually optimized to perform various processing operations. For example, processing modules 920a-920d may be implemented to perform deposition, evaporation, ELD, dry development, cleaning, etching, processing, stripping, and / or other semiconductor processes. For example, module 920a may be an ALD reactor operable to perform thermal atomic layer deposition in a non-plasma as described herein. Module 920b may be a PECVD tool. It should be understood that the drawings are not necessarily drawn to scale.

[0302] Airlocks 942 and 946 (also known as load locks or transfer modules) are connected to VTM 938 and patterning module 940. This tool architecture enables a workpiece (such as a semiconductor substrate or wafer) to be transferred under vacuum so that it does not react before exposure. The integration of the deposition module and the lithography tool is facilitated by the fact that EUVL also requires very low pressures, assuming strong light absorption of incident photons by ambient gases (such as H2O, O2, etc.).

[0303] As described above, this integrated architecture is only one possible example of a tool for the implementation of the described processes. The processes may be implemented by a more conventional stand-alone EUVL scanner and a deposition reactor integrated as a module in a cluster architecture with other tools such as etching, stripping, etc., as described with reference to FIG. 9, except that there is no stand-alone or, for example, integrated patterning module.

[0304] Airlock 942 may be an "unloading" load lock with reference to removing the substrate from VTM 938 that supplies deposition module 920a to patterning module 940, and airlock 946 may be a "loading" load lock with reference to returning the substrate from patterning module 940 to VTM 938. The loading airlock 946 may also provide an interface with the outside of the tool for access and unloading of the substrate. Each processing module has a facet that connects the module to VTM 938. For example, deposition processing module 920a has facet 936. Within each facet, sensors (such as sensors 1-18 in the figure) are used to detect the passage of wafer 926 when wafer 926 is moved between respective stations. Patterning module 940 and airlocks 942 and 946 may similarly be provided with additional facets and sensors not shown.

[0305] The main VTM robot 922 transfers the wafer 926 between modules including airlocks 942 and 946. In one embodiment, the robot 922 has one arm, and in another embodiment, the robot 922 has two arms, and each arm has an end effector 924 for gripping a wafer (such as wafer 926) for transfer. The front-end robot 944 is used to transfer the wafer 926 from the outfeed airlock 942 to the patterning module 940 and from the patterning module 940 to the infeed airlock 946. The front-end robot 944 may transport the wafer 926 between the infeed load lock and the outside of the tool for access and outfeed of the substrate. The infeed airlock module 946 can be adjusted to the environment between atmosphere and vacuum, so that the wafer 926 can move between the two pressure environments without being damaged.

[0306] Note that EUVL tools typically operate at a higher vacuum than deposition tools. In this case, it is preferable to increase the vacuum environment of the substrate during transfer from the deposition tool to the EUVL tool to enable degassing of the substrate before it enters the patterning tool. The outfeed airlock 942 provides this function by holding the wafer to be transferred at a lower pressure (below the pressure inside the patterning module 940) for a period of time and exhausting all off-gases so that the optical system of the patterning module 940 is not contaminated by off-gases from the substrate. A suitable pressure for the outfeed off-gas airlock is 1E-8 Torr or less.

[0307] In some embodiments, a controller 950 (which may include one or more physical or logical controllers) controls some or all of the operation of the cluster tool and / or its separate modules. Note that the controller may be located locally to the cluster structure, or may be located outside, i.e., remotely from, the cluster structure within the manufacturing floor and connected to the cluster structure via a network. Controller 950 may comprise one or more memory devices and one or more processors. The processor may comprise a central processing unit (CPU) or computer, analog and / or digital input / output connections, a stepper motor controller board, and other similar components. Instructions for performing appropriate control operations are executed by the processor. These instructions may be stored in a memory device associated with the controller, or may be provided via a network. In certain embodiments, the system controller executes system control software.

[0308] The system control software may comprise instructions for controlling the timing and / or degree of application of any aspect of the tool or module operation. The system control software may be configured in any suitable manner. For example, various processing tool component subroutines or control objects may be written to control the operation of the processing tool components necessary to execute the processing of the various processing tools. The system control software may be coded in any suitable computer-readable programming language. In some embodiments, the system control software comprises input / output control (IOC) sequencing instructions for controlling the various parameters described above. For example, each stage of a semiconductor manufacturing process may comprise one or more instructions for execution by a controller. Instructions for setting processing conditions for condensation, deposition, evaporation, patterning, and / or etching stages may be included, for example, in the corresponding recipe stage.

[0309] In various embodiments, an apparatus for post-development processing is provided. The apparatus may comprise a processing chamber for patterning, processing, deposition, and etching, and a controller including instructions for post-development processing of a patterned photoresist mask. The instructions may include code for processing a patterned metal-containing photoresist mask after development within the processing chamber. Such processing may include heat treatment, plasma treatment, chemical treatment, or selective deposition of a protective layer onto the patterned metal-containing photoresist mask.

[0310] Note that a computer controlling the movement of the wafer may be located locally to the cluster architecture or may be located outside, i.e., remotely from, the cluster architecture within the manufacturing floor and connected to the cluster architecture via a network. A controller as described above with respect to any of FIGS. 6, 7, or 8 may be implemented with the tool of FIG. 9.

[0311] Further Examples The apparatus and processes described herein may be used, for example, with lithographic patterning tools or processes for the fabrication or manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, etc. Although not necessarily so, typically such apparatus and processes are utilized or executed together in a common manufacturing facility. Lithographic patterning of thin films typically includes some or all of the following steps, each of which may be implemented with a plurality of possible tools. (1) A step of applying a photoresist onto a workpiece (i.e., a substrate) using a spin-on or spray-on tool; (2) A step of curing the photoresist using a hot plate or furnace or UV curing tool; (3) A step of exposing the photoresist to visible light or UV or X-rays using a tool such as a wafer stepper; (4) A step of developing the resist to pattern it by selectively removing the resist using a tool such as a wet bench; (5) A step of transferring the resist pattern to the underlying film or workpiece using a dry etching tool or a plasma-assisted etching tool; and (6) A step of removing the resist using a tool such as an RF plasma or microwave plasma resist stripper.

[0312] Conclusion For purposes of enhancing understanding, this embodiment has been described in some detail, but it is clear that some changes and modifications may be made within the scope of the appended claims. Note that there are many other ways to implement the processes, systems, and apparatus of the present invention. Accordingly, this embodiment is to be regarded as illustrative and not restrictive, and the embodiment is not limited to the details shown herein.

Claims

1. A method for performing both dry development and passivation of a metal-containing photoresist within a single processing chamber, comprising: providing a patterned metal-containing photoresist on a semiconductor substrate within the processing chamber; thermally dry-developing the patterned metal-containing photoresist with a processing gas at a first pressure to form a thermally dry-developed patterned metal-containing photoresist; passivating the thermally dry-developed patterned metal-containing photoresist at a second pressure that is different from or the same as the first pressure within the same processing chamber as the thermal dry development of the patterned metal-containing photoresist to form a patterned substrate; A method comprising the above steps.

2. The method of claim 1, wherein the second pressure is lower than the first pressure.

3. The method of claim 1, wherein passivating comprises exposing to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

4. The method according to claim 1, wherein the passivation is carried out by O ２ O ３ CO, CO ２ H ２ C ｘ H ｙ H ２ OH, H ２ O ２ SO ２ NO, NO ２ N ２ NO, NH ３ or a flash treatment using a combination thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14.

5. The method of claim 4, wherein the flash treatment is performed over a duration of from about 0.5 to about 10 seconds.

6. The method of claim 1, wherein the throughput of the semiconductor substrate is increased by at least about 50%.

7. The method of claim 1, wherein the metal-containing photoresist comprises an organometal containing a photo-patterned EUV-sensitive organometallic oxide, a photo-patterned EUV-sensitive metal oxide, or a thin film EUV resist.

8. The method of claim 7, wherein the photo-patterned EUV-sensitive metal oxide comprises tin oxide.

9. The method of claim 8, wherein the release of tin gas from the tin oxide is mitigated.

10. The method of claim 1, wherein thermally dry-developing comprises a treatment using a halogen-containing gas.

11. The method of claim 1, further comprising plasma dry-developing the thermally dry-developed patterned metal-containing photoresist, wherein thermally dry-developing, plasma dry-developing, and passivating are all performed within the same processing chamber.

12. The method according to claim 11, wherein the thermal dry development and the plasma dry development are alternately repeated.

13. The method according to claim 11, wherein the plasma dry development is cyclic dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

14. The method according to claim 13, wherein the plasma dry development is continuous plasma dry development, and the continuous plasma dry development is performed at variable power, constant power and pulse bias, or variable power and pulse bias.

15. The method according to claim 11, wherein the plasma dry development includes a process using a plasma of at least one halogen-containing gas in an inert carrier gas.

16. The method according to claim 15, wherein the halogen-containing gas is HBr, Br ２ , HCl, Cl ２ , HI, I ２ , or BCl ３ .

17. The method according to claim 1, wherein the first pressure is about 5 mTorr to 760 Torr, and the second pressure is about 5 mTorr to 200 mTorr.

18. The method according to claim 1, wherein the second pressure is the same as the first pressure.

19. The method according to claim 11, further comprising shifting the pressure in the same processing chamber from the first pressure to the second pressure within 10 seconds, returning the pressure in the same processing chamber from the second pressure to the first pressure within 20 seconds after plasma dry development and passivation, maintaining one or more processing parameters uniformly. A method comprising the above.

20. The method according to claim 1, further comprising curing the metal-containing photoresist after passivation in the same processing chamber as the processing chamber used for the thermal dry development.

21. The method according to claim 11, further comprising curing the metal-containing photoresist after passivation in the same processing chamber as the processing chamber used for the thermal dry development, plasma dry development, and passivation.

22. The method according to claim 20 or 21, wherein the curing is performed by a process using a plasma of an inert gas, a process using a plasma of an oxidizing gas, a heat treatment, UV light exposure, or a combination thereof.

23. An apparatus for performing both dry development and passivation of a metal-containing photoresist within a single processing chamber, one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to the pressure regulators, a plasma processing system, one or more gas inlets to the processing chamber and associated flow control hardware, a controller having at least one processor and a memory, comprising, the at least one processor and the memory are communicatively connected to each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to perform thermal dry development in one of the processing chambers and perform passivation in the same processing chamber as the thermal dry development.

24. The apparatus according to claim 23, wherein the thermal dry development is performed at a first pressure and the passivation is performed at a second pressure below the first pressure.

25. The apparatus according to claim 23, further comprising a photoresist thickness sensor module.

26. The apparatus according to claim 25, wherein the photoresist thickness sensor module is a spectral reflectometer.

27. The apparatus according to claim 23, further comprising computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to perform plasma dry development, and both the plasma dry development and the passivation are performed within the same processing chamber.

28. The apparatus according to claim 27, wherein the plasma dry development is cyclic dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

29. The apparatus according to claim 28, wherein the plasma dry development is continuous plasma dry development, and the continuous plasma dry development is performed at variable power, constant power and pulse bias, or variable power and pulse bias.

30. The apparatus according to claim 23, wherein the passivation is a treatment using an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

31. The apparatus according to claim 23, wherein the passivation is O ２ O ３ CO, CO ２ H ２ C ｘ H ｙ H ２ O, H ２ O ２ SO ２ NO, NO ２ N ２ O, NH ３ or a flash treatment using a combination thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14.

32. The apparatus according to claim 24, wherein the second pressure is lower than the first pressure.

33. The apparatus according to claim 32, further comprising shifting the pressure in the same processing chamber from the first pressure to the second pressure within 10 seconds, returning the pressure in the same processing chamber from the second pressure to the first pressure within 20 seconds after plasma dry development and passivation, computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to maintain one or more processing parameters uniformly.

34. An apparatus for performing dry development, passivation, and curing of a metal-containing photoresist all in one processing chamber, comprising one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to the pressure regulator, one or more gas inlets to the processing chamber and associated flow control hardware, a plasma processing system, a controller having at least one processor and a memory, wherein the at least one processor and the memory are communicably connected to each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to perform dry development in one of the processing chambers and perform passivation and curing in the same processing chamber as the dry development.

35. The apparatus according to claim 34, wherein the dry development includes thermal dry development and plasma dry development.

36. The apparatus according to claim 34, wherein the dry development is performed at a first pressure, and the passivation and the curing are performed at a second pressure.

37. The apparatus according to claim 36, wherein the second pressure is less than or equal to the first pressure.

38. The apparatus according to claim 34, further comprising a photoresist thickness sensor module.

39. The apparatus according to claim 38, wherein the photoresist thickness sensor module is a spectral reflectometer.

40. The apparatus according to claim 34, wherein the curing is performed by a treatment using a plasma of an inert gas, a treatment using a plasma of an oxidizing gas, a heat treatment, UV light exposure, or a combination thereof.

41. The apparatus according to claim 34, wherein the passivation is a treatment using an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

42. The apparatus according to claim 34, wherein the passivation is performed by a flash treatment using O ２ O ３ CO, CO ２ H ２ C ｘ H ｙ H ２ OH, H ２ O ２ SO ２ NO, NO ２ N ２ OH, NH ３ or a combination thereof, and x is an integer from 1 to 6, and y is an integer from 2 to 14.

43. The apparatus according to claim 35, wherein the plasma dry development is cyclic dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

44. The apparatus according to claim 43, wherein the plasma dry development is continuous plasma dry development, and the continuous plasma dry development is performed with variable power, constant power and pulse bias, or variable power and pulse bias.

45. The apparatus according to claim 34, further comprising a UV exposure module.

46. The apparatus according to claim 36, wherein the second pressure is lower than the first pressure.

47. The apparatus according to claim 46, further comprising shifting the pressure in the same processing chamber from the first pressure to the second pressure within 10 seconds, returning the pressure in the same processing chamber from the second pressure to the first pressure within 20 seconds after plasma dry development and passivation, computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to maintain one or more processing parameters uniformly.

48. A method for performing all of thermal dry development and plasma dry development in a single processing chamber, comprising: providing a metal-containing photoresist on a semiconductor substrate in a processing chamber; performing thermal dry development of the metal-containing photoresist in the processing chamber; performing plasma dry development of the metal-containing photoresist in the processing chamber.

49. The method according to claim 48, wherein said heat dry development includes exposure to a first processing gas, and said plasma dry development includes exposure to a plasma of a second processing gas different from said first processing gas.

50. The method according to claim 49, wherein said first processing gas includes a halogen-containing gas, and said second processing gas includes an inert gas, a halogen-containing gas, or a combination thereof.

51. The method according to claim 50, wherein said first processing gas includes hydrogen halide.

52. The method according to claim 48, wherein said heat dry development is carried out at a first pressure, and said plasma dry development is carried out at a second pressure different from said first pressure.

53. The method according to claim 48, wherein said heat dry development and said plasma dry development are carried out at a temperature of about -20°C to about 50°C in said processing chamber.

54. The method according to claim 48, wherein said heat dry development and said plasma dry development are alternately repeated.

55. The method according to claim 48, further comprising performing a post-treatment for dry development in said processing chamber.

56. The method according to claim 55, wherein said post-treatment for dry development includes passivating said metal-containing photoresist in said processing chamber.

57. The method according to claim 56, wherein said passivating includes exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

58. The method according to claim 55, wherein said post-treatment for dry development includes curing said metal-containing photoresist in said processing chamber.

59. The method according to claim 58, wherein said curing includes treatment using a plasma of an inert gas, treatment using a plasma of an oxidizing gas, heat treatment, UV light exposure, or a combination thereof.

60. An apparatus for performing heat dry development and plasma dry development of a metal-containing photoresist in a single processing chamber, comprising: one or more processing chambers; one or more pressure adjustment devices; one or more pumps fluidly connected to said pressure adjustment devices; a plasma processing system; one or more gas inlets to the processing chamber and associated flow control hardware, a controller having at least one processor and memory, comprising, the at least one processor and the memory are communicatively connected to each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to perform thermal dry development in one of the processing chambers and plasma dry development in the same processing chamber as the thermal dry development, an apparatus.

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