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

Abstract

The process condition management facilitates 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. Thermal dry development and plasma dry development may be performed in the same chamber. The operations of thermal dry development, plasma dry development, and passivation (O2 flash processing), or thermal dry development, plasma dry development, passivation, and curing are possible without wafer transfer.

Description

cross reference

[0001] A PCT Request Form is being filed contemporaneously herewith as part of this application. Each application to which this application claims benefit or priority as identified in the contemporaneously filed PCT Request Form is incorporated herein by reference in its entirety for all purposes. [Background technology]

[0002] The fabrication of semiconductor devices, such as integrated circuits, is a multi-step process that involves photolithography. Generally, the process involves depositing material on a wafer and patterning the material lithographically to form the structural features (e.g., transistors and circuits) of the semiconductor device. Typical photolithography process steps include preparing a substrate, applying photoresist, such as by spin coating, exposing the photoresist in 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, such as by etching or deposition of material, to form features on the areas of the substrate where the photoresist was removed.

[0003] The evolution of semiconductor design has created a need and been driven by the ability to form ever smaller features on semiconductor substrate materials. One challenge in fabricating devices with such small features is the ability to reliably and reproducibly generate photolithography masks with sufficient resolution. Current photolithography processes typically utilize 193 nm ultraviolet (UV) light to expose photoresist. A unique problem arises because the light has a wavelength significantly longer than the desired size of the features to be formed on the semiconductor substrate. Achieving feature sizes smaller than the wavelength of the light requires the use of complex resolution enhancement techniques (e.g., multi-patterning). Therefore, there has been significant interest in, and research efforts toward, photolithography techniques that utilize short-wavelength light (e.g., extreme ultraviolet radiation (EUV)) with wavelengths between 10 nm and 15 nm (e.g., 13.5 nm).

[0004] However, EUV photolithography processes can present challenges such as low power, light loss during patterning, and metal cross-contamination due to metal outgassing. Therefore, there remains a need for improved EUV photoresist processes that more efficiently produce materials with desired properties.

[0005] The background art provided herein is intended to provide a general background to the present disclosure, and the work of the inventors named herein, to the extent described in this background art, along with aspects of the description that would not normally be considered prior art at the time of filing, are not admitted expressly or impliedly as prior art to the present disclosure. Summary of the Invention

[0006] The present disclosure relates to methods and apparatus for integrating dry development processing into the same processing chamber. In some embodiments, the present disclosure relates to methods and apparatus for integrating dry development and post-dry development processing into the same processing chamber. This integration of processing metal-containing photoresist surfaces improves throughput and reduces wafer handling, increasing semiconductor manufacturing efficiency through higher wafer productivity and better lithography control. The integrated processing also improves device yield / defect performance. The post-dry development processing includes plasma passivation. Additionally or alternatively, the post-dry development processing may include hardening. The post-dry development processing of plasma passivation and / or hardening in a flash process may all be performed in a single processing chamber in conjunction with dry development, eliminating the need for a post-dry development bake that would otherwise be performed in a separate chamber or tool. The integrated method also achieves surface smoothing and mitigates contaminant outgassing through passivation.

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

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

[0009] In some embodiments, the passivating is performed using O, O, CO, CO, H, Cx H y , H2O, H2O2, SO2, NO, NO2, N2O, NH3, or mixtures thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14.

[0010] In some embodiments, the flashing process is carried out for a duration of from about 0.5 to about 10 seconds.

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

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

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

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

[0015] In some embodiments, the thermal dry developing comprises 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, wherein the thermal dry developing, plasma dry developing, and passivating are all performed in the same processing chamber.

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

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

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

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

[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 between about 5 mTorr and 760 Torr, and the second pressure is between about 5 mTorr and 200 mTorr.

[0023] In some embodiments, the first pressure is less 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 uniform.

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

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

[0027] In some embodiments, the curing is carried out 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.

[0028] In a second aspect, the present disclosure includes an apparatus for performing dry development and passivation of a metal-containing photoresist all in 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 chambers and associated flow control hardware, and a controller having at least one processor and memory, wherein the at least one processor and memory are communicatively coupled to each other, and the at least one processor is at least operatively coupled 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 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 that is equal to or less than 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 the at least one processor to at least control associated flow control hardware to perform plasma dry development, wherein the plasma dry development and passivation are all performed within the same processing chamber.

[0032] In some embodiments, 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, where the continuous plasma dry development is performed at variable power, at constant power and pulsed bias, or at variable power and pulsed bias.

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

[0035] In some embodiments, passivation is achieved by the addition of O, O, CO, CO, H, 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 less than the second pressure.

[0037] In some embodiments, the apparatus further comprises computer-executable instructions for controlling the at least one processor to at least control 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 developing and passivation, and to maintain uniformity of one or more processing parameters.

[0038] In a third aspect, the present disclosure includes an apparatus for performing dry development, passivation, and curing of a metal-containing photoresist all 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 chambers and associated flow control hardware, a plasma processing system, and a controller having at least one processor and memory, wherein the at least one processor and memory are communicatively coupled to each other, and the at least one processor is at least operatively coupled 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, the curing is carried out 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 comprises exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

[0043] In some embodiments, passivation is achieved by the addition of O, O, CO, CO, H, 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, the plasma dry development includes continuous plasma dry development, where the continuous plasma dry development is performed at variable power, at constant power and pulsed bias, or at variable power and pulsed bias.

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

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

[0048] In some embodiments, the apparatus further comprises computer-executable instructions for controlling the at least one processor to at least control 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 developing and passivation, and to maintain uniformity of one or more processing parameters.

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

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

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

[0052] In some embodiments, the thermal dry developing and plasma dry developing are carried out at a temperature of about -20°C to about 50°C in the processing chamber.

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

[0054] In some embodiments, the method further comprises performing a dry development post-treatment in the processing chamber. In some embodiments, the dry development post-treatment includes passivating the metal-containing photoresist in 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 dry development post-treatment may include hardening the metal-containing photoresist in the processing chamber. Hardening may include treatment with a plasma of an inert gas, treatment with a plasma of an oxidizing gas, a thermal treatment, UV light exposure, or a combination thereof.

[0055] In a fifth aspect, the present disclosure includes an apparatus for performing thermal dry development and plasma dry development of a metal-containing photoresist all in 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 pressure regulators, a plasma processing system, one or more gas inlets to the processing chambers and associated flow control hardware, and a controller having at least one processor and memory, wherein the at least one processor and memory are communicatively coupled to each other, and the at least one processor is at least operatively coupled 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 to perform plasma dry development in the same processing chamber as the thermal dry development.

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

[0057] [Figure 1] 1 is a flow chart illustrating a process for depositing, developing, and treating photoresist.

[0058] [Figure 2A] Schematic cross-sectional views showing various processing stages including photoresist development and treatment. [Figure 2B] Schematic cross-sectional views showing various processing stages including photoresist development and treatment. [Figure 2C] Schematic cross-sectional views showing various processing stages including photoresist development and treatment.

[0059] [Figure 3] 1 is a flow chart illustrating an example method of an overall process including photoresist development in a single processing chamber in accordance with certain disclosed embodiments.

[0060] [Figure 4A] 4 is a flow chart illustrating an example method for performing dry development and passivation operations in the same processing chamber in accordance with certain disclosed embodiments.

[0061] [Figure 4B] 1 is a flow chart illustrating an example method for performing thermal dry development and plasma dry development operations in the same processing chamber in accordance with certain disclosed embodiments.

[0062] [Figure 4C] 1 is a flow chart illustrating an example method for performing dry developing and curing operations in the same processing chamber, in accordance with certain disclosed embodiments.

[0063] [Figure 4D] 4 is a flow chart illustrating an example method for performing thermal dry development, plasma dry development, and passivation operations in the same processing chamber in accordance with certain disclosed embodiments.

[0064] [Figure 4E] 1 is a flow chart illustrating an example method for performing dry development, passivation, and curing operations in the same processing chamber in accordance with certain disclosed embodiments.

[0065] [Figure 5A] 1A-1C are schematic cross-sectional views illustrating various processing stages including thermal dry development, plasma dry development, and passivation in accordance with certain disclosed embodiments. [Figure 5B] 1A-1C are schematic cross-sectional views illustrating various processing stages including thermal dry development, plasma dry development, and passivation in accordance with certain disclosed embodiments. [Figure 5C] 1A-1C are schematic cross-sectional views illustrating various processing stages including thermal dry development, plasma dry development, and passivation in accordance with certain disclosed embodiments. [Figure 5D] 1A-1C are schematic cross-sectional views illustrating various processing stages including thermal dry development, plasma dry development, and passivation in accordance with certain disclosed embodiments. [Figure 5E] 1A-1C are schematic cross-sectional views illustrating various processing stages including thermal dry development, plasma dry development, and passivation in accordance with certain disclosed embodiments.

[0066] [Figure 6] FIG. 1 is a schematic diagram illustrating an example of a processing station for maintaining a suitable environment for performing photoresist development operations and other photoresist processing operations in accordance with certain disclosed embodiments.

[0067] [Figure 7] 1 is a schematic diagram illustrating an example of a multi-station processing tool suitable for performing photoresist development operations and other photoresist processing operations in accordance with certain disclosed embodiments.

[0068] [Figure 8] 1 is a schematic cross-sectional view illustrating an example of an inductively coupled plasma apparatus for carrying out certain embodiments and operations described herein in accordance with certain disclosed embodiments.

[0069] [Figure 9]FIG. 1 illustrates a semiconductor processing cluster tool architecture with a vacuum-integrated deposition module and patterning module coupled to a vacuum transfer module, suitable for performing the processes described herein, in accordance with certain disclosed embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0070] In the following description, numerous specific details are set forth to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. Additionally, detailed descriptions of well-known process operations are omitted to avoid unnecessarily obscuring the disclosed embodiments. While the disclosed embodiments are described in connection with specific embodiments, it should be understood that they 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 with a processing chamber. Flow control hardware can 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 "forming a gas mixture" generally refers to either or both mixing multiple gases prior to introducing the multiple gases into the processing chamber or mixing multiple gases within the processing chamber.

[0073] The term "inert gas" generally refers to a gas-phase material that does not react with other chemicals in 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 refers to a gas containing positive ions, free radicals, and free electrons. The term "in situ plasma" generally refers to a plasma formed at a processing station within a processing chamber. The term "remote plasma" generally refers to a plasma formed at a location remote from a processing station within a processing chamber.

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

[0076] The term "precursor" generally refers to 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 terms "processing chamber" or "process chamber" generally refer to a container in which chemical and / or physical processes are performed on a substrate. The pressure, substrate temperature, and atmospheric composition within the processing chamber may be controllable to perform chemical and / or physical processes.

[0078] The term "processing tool" generally refers to a machine that includes a processing chamber and hardware configured to enable a process to be performed in the processing chamber.

[0079] The term "processing station" generally refers to the location within a processing chamber where a substrate is positioned during processing.

[0080] The term "reactant" refers to a chemical species that reacts with a precursor adsorbed on the substrate surface to form a film layer during an ALD process. The reaction between the reactant and precursor can be facilitated 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 fabrication that includes semiconductor material somewhere within its structure. It is understood that the semiconductor material in a 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. The following detailed description assumes that the disclosed embodiments are implemented on a semiconductor wafer (such as a 200 mm, 300 mm, or 450 mm semiconductor wafer), although the disclosed embodiments are not so limited. Workpieces may have a variety of shapes, sizes, and materials. In addition to semiconductor wafers, other workpieces that may 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 (e.g., a wafer, substrate, or other workpiece). Workpieces can have a variety of shapes, sizes, and materials. The terms “semiconductor wafer,” “wafer,” “substrate,” “wafer substrate,” and “partially fabricated integrated circuit” are used interchangeably herein. Those skilled in the art will recognize that the term “partially fabricated integrated circuit” can refer to a silicon wafer during any of the many stages of integrated circuit manufacturing. Wafers or substrates used in the semiconductor device industry typically have diameters of 200 mm, 300 mm, or 450 mm. Unless otherwise specified, process details (e.g., flow rates, power levels, etc.) described herein are suitable for processing 300 mm diameter substrates or for handling chambers configured to process 300 mm diameter substrates and may be scaled to suit substrates or chambers of other sizes. In addition to semiconductor wafers, other workpieces that can be used with the embodiments disclosed herein include various items, such as printed circuit boards. The processes and equipment can be used in the manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, and the like.

[0083] As used herein, the term "photoresist" and its derivatives refer to a photosensitive material used in processes (such as photolithography, photoetching, or photoengraving) to form patterned coatings on surfaces. Photoresist materials change their solubility in a developer when exposed to light of a specific wavelength. Photoresist layers can be composed of positive-acting (exposed areas become soluble) or negative-acting (exposed areas become insoluble) photoresist materials.

[0084] For purposes of this disclosure, "metal" as used in this context will be understood to mean electrical conductors having a maximum resistivity of 500 micro-Ω cm, such as metals and conductive metal salts (particularly conductive metal nitrides, e.g., TiN).

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

[0086] "Tin oxide" is used herein to refer to Sn, including integer values ​​of x and y as well as non-integer values ​​of x and y. x O y For example, "tin oxide" has the formula SnO n where 1≦n≦2, and n can be an integer or a non-integer value. "Tin oxide" refers to the substoichiometric compounds (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 crystalline and molecular structures. "Tin oxide" also includes amorphous tin oxide.

[0087] As used herein, the phrase "at least one of A, B, and C" should be interpreted to mean the logical (A or B or C) using the non-exclusive logical "or," and not 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 contemplate slight variations above and / or below the stated value, where the variation does not significantly affect the desired function of the parameter outside the stated value. In some cases, "about" includes + / - 10% of any stated value. As used herein, the term modifies any stated value, range of values, or one or more endpoints of a range.

[0089] As used herein, the terms "top," "bottom," "upper," "lower," "above," and "below" are used to indicate relative relationships between structures. Use of these terms does not indicate or require that a particular structure be located in a particular position on 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 developing photoresists, such as metal-containing photoresists. Such metal-containing and / or metal oxide-containing photoresists can undergo one or both of thermal dry development and / or plasma dry development. Such metal-containing and / or metal oxide-containing photoresists can be treated after development and before pattern transfer to alter the chemical, physical, and / or optical properties of the photoresist. Treating the photoresist improves photoresist performance. For example, photoresist treatment can reduce dose-to-size (DtS), reduce line width roughness (LWR), increase line CD, improve etch resistance, increase throughput, reduce outgassing of tin or other elements, and / or reduce defects / opens. Throughput can be increased by at least about 40%, 50%, 60%, 70%, 80%, or 90%.

[0091] Patterning of thin films in semiconductor processing is often a critical step during semiconductor manufacturing. Patterning involves lithography. In traditional photolithography (such as 193 nm photolithography), patterns are printed onto a light-sensitive photoresist film by exposing the photoresist to photons in selective areas defined by a photomask, causing chemical reactions in the exposed photoresist, creating chemical contrasts that can be used in a development process to remove specific portions of the photoresist and form the pattern. The patterned and developed photoresist film can then be used as an etch mask to transfer the pattern to underlying films composed of metals, oxides, etc.

[0092] Advanced technology nodes (defined by the International Technology Roadmap for Semiconductors) include 22 nm, 16 nm, and beyond. For example, at the 16 nm node, via or line widths in damascene structures are typically about 30 nm or less. The scaling of features in advanced semiconductor integrated circuits (ICs) and other devices is driving improvements in lithographic resolution.

[0093] Extreme ultraviolet (EUV) lithography can extend lithography technology by moving to shorter imaging source wavelengths than can be achieved with conventional photolithography methods. EUV sources with wavelengths of approximately 10-20 nm or 11-14 nm (e.g., 13.5 nm wavelength) are available for modern lithography tools (also called scanners). EUV radiation is strongly absorbed by a wide range of solid and fluid materials, including quartz and water vapor, and is therefore applied in a vacuum.

[0094] EUV lithography utilizes a patterned EUV resist to form a mask for use in etching an underlying layer. The EUV resist may be a polymeric chemically amplified resist (CAR) produced by a liquid-based spin-on technique. An alternative to CAR is a directly photopatternable metal oxide-containing film (such as those manufactured by Inpria, Inc., Corvallis, Oregon), as described, for example, in U.S. Patent Publication Nos. US2017 / 0102612, US2016 / 0216606, and US2016 / 0116839, which are incorporated herein by reference for their disclosure at least regarding photopatternable metal oxide-containing films. Such films may be formed by spin-on techniques or dry-deposited. Metal oxide-containing films can be patterned directly (i.e., without utilizing a separate photoresist) by EUV exposure in a vacuum atmosphere to provide patterning resolution of less than 30 nm, as described, for example, in U.S. Pat. No. 9,996,004, issued June 12, 2018, entitled "EUV PHOTOPATTERNING OF VAPOR-DEPOSITED METAL OXIDE-CONTAINING HARD MASKS," and / or International Application No. PCT / US19 / 31618, filed May 9, 2019, and published as International Publication No. WO2019 / 217749, the disclosures of which, at least, relate to the composition, deposition, and patterning of directly photopatternable metal oxide films to form EUV resist masks, which are incorporated herein by reference. Generally, patterning involves exposing the EUV resist to EUV radiation to form a photopattern in the resist, followed by development to remove portions of the resist according to the photopattern to form a mask.

[0095] Directly photopatternable EUV or DUV resists may be composed of or include metals and / or metal oxides mixed within an organic component. The metals / metal oxides may promote EUV or DUV photon absorption, generate secondary electrons, and / or exhibit high etch selectivity relative to underlying film stacks and device layers. These resists can be developed using a wet (solvent) approach, which requires moving the wafer on a track where it 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] In general, resists can be utilized as positive or negative tone resists by controlling the resist chemistry and / or developer solubility or reactivity. It would be beneficial to have an EUV or DUV resist that can function as either a negative or positive tone resist.

[0097] While the following describes techniques related to EUV processing, such techniques may also be applicable to other next-generation lithography technologies. A variety of radiation sources may be used, including EUV (typically around 13.5 nm), DUV (deep UV, typically in the 248 nm or 193 nm range with excimer laser sources), X-ray (including EUV in the low energy range of the X-ray range), and e-beam (including a wide energy range).

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

[0099] At block 102 of process 100, a layer of photoresist is deposited. This can be either a dry deposition process (such as an evaporation process) or a wet deposition process (such as a spin-on deposition process). 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 vapor form 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., a tin-containing precursor, such as any precursor described herein) 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 vapor form using a dry technique (e.g., chemical vapor deposition). While this disclosure often refers to the metal-containing precursor as a tin-containing precursor, other metal atoms may be used.

[0101] The layers and films described herein are 7 cm 2The imaging layer may include an element (e.g., a metal atom or a non-metal atom) having a high optical absorption cross section, such as 1 / mol or less. Such an element may be provided by depositing one or more precursors to provide the 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 can include one or more ligands (e.g., EUV-labile ligands) that can be removed, cleaved, or crosslinked by radiation (e.g., EUV or DUV radiation).

[0103] The precursor can provide a patternable film that is sensitive to radiation (or a patterned radiation-sensitive film or photopatternable film). Such radiation can include EUV radiation, DUV radiation, or UV radiation, delivered by irradiating through a patterned mask to result in patterned radiation. The film itself can be modified by exposure to such radiation to make the film radiation-sensitive or photosensitive. In certain embodiments, the precursor is an organometallic compound and includes at least one metal center.

[0104] The precursor may have any useful number and type of ligands. In some embodiments, the ligands may be characterized by their ability to react in the presence of a counter-reactant or in the presence of patterned radiation. For example, the precursor may include a ligand that reacts with a counter-reactant, thereby introducing a bond (e.g., an -O- bond) between the metal centers. In another example, the precursor may include 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 2In 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 SnF, SnH, SnBr, SnCl, SnI, tetramethyltin (SnMe), tetraethyltin (SnEt), trimethyltin chloride (SnMeCl), dimethyltin dichloride (SnMeCl), methyltin trichloride (SnMeCl), tetraallyltin, tetravinyltin, hexaphenylditin(IV) (PhSn-SnPh, where Ph is phenyl), dibutyldiphenyltin (SnBuPh), and the like. 2), 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-diazastannolidin-2-ylidene), or bis[bis(trimethylsilyl)amino]tin (Sn[N(SiMe3)2]2).

[0107] Examples of deposition techniques (e.g., for films) include any of the techniques described herein, such as 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, e-beam evaporation including e-beam co-evaporation, or combinations thereof (e.g., combining ALD and CVD components, discontinuous ALD-like processes in which precursors and counter reactants are separated in time or space, etc.).

[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 May 9, 2019, and published as International Publication No. WO2019 / 217749. The thin films may include optional materials in addition to the precursors and counter reactants to alter the chemical or physical properties of the film, such as to modify the film's sensitivity to EUV or increase its etch resistance. Such optional materials may be introduced, such as by doping during deposition onto the substrate, during deposition onto the substrate, and / or during vapor phase formation after deposition onto the substrate. In some embodiments, a mild remote H plasma may be introduced, for example, to replace some Sn-L bonds with Sn-H, thereby enhancing the reactivity of the resist under EUV. In other embodiments, CO2 may be introduced to replace some Sn-O bonds with Sn-CO3 bonds, the latter bonds may be more resistant to wet development.

[0109] Various atoms present in the precursor and / or counter reactant can be provided in a capping layer, which is then disposed over any useful layer or structure. The capping layer can be of any useful thickness (e.g., any thickness described herein, such as from about 0.1 nm to about 5 nm).

[0110] Additionally, two or more different precursors may be utilized within each layer (e.g., a membrane or capping layer). For example, two or more of any metal-containing precursors herein may be utilized to form an alloy. Further exemplary EUV-sensitive materials and processing methods and apparatus are described in U.S. Pat. No. 9,996,004, International Patent Publication No. WO2020 / 102085, and International Patent Publication No. WO2019 / 217749, each of which is incorporated herein by reference in its entirety.

[0111] In some embodiments, a photoresist film may be deposited on an underlayer. In some embodiments, the underlayer may be deposited on a hard mask, such as an ashable hard mask (AHM). The underlayer is configured to enhance adhesion between a subsequently formed EUV resist and the substrate. The underlayer is also configured to reduce the EUV dose for effective EUV exposure of the EUV resist. The underlayer may include a deposited film of hydrogenated carbon 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 underlayer including a hydrogenated carbon film doped with iodine may improve secondary electron generation in the EUV resist upon exposure to EUV radiation. The underlayer may have a thickness of about 25 nm or less (e.g., between about 2 nm and about 20 nm). In some examples, the underlayer may be deposited using a vapor deposition technique (such as PECVD or ALD).

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

[0113] At block 106 of process 100, a post-apply bake (PAB) or post-apply treatment can optionally be performed. Such treatment can improve the etch resistance of unexposed materials to aqueous or non-aqueous solutions. In one example, such treatment can enhance the difference (or contrast) in chemical composition between unexposed and exposed regions, and therefore a PAB operation is performed. In another example, such treatment can reduce the difference (or contrast) in chemical composition between unexposed and exposed regions, and therefore a PAB operation is not performed. In yet another example, the use of PAB removes residual moisture from the film to form a hardened resist film. PAB can include a combination of thermal 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 step is performed at a temperature greater than about 100°C, or between about 100°C and about 200°C, or between about 100°C and about 250°C. In another embodiment, the PAB process is carried out 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] At block 108 of process 100, the film is exposed to EUV radiation to develop a pattern. Generally, EUV exposure alters the chemical composition of the film, creating an etch selectivity contrast that can be utilized to remove portions of the film. Such contrast can provide a positive-tone resist. However, it is understood that EUV exposure can instead induce a contrast such that unexposed (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 have altered physical or chemical properties relative to the less exposed areas, which are created through photopatterning. The difference in properties between the more exposed and 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 in a vacuum atmosphere (e.g., about 13.5 nm in a vacuum atmosphere).

[0115] At block 110 of process 100, a post-exposure bake (PEB) is performed on the exposed film to further remove residual moisture, promote chemical concentration within the film, or enhance the contrast of the etch selectivity of the exposed film, or post-treat the film in any useful manner. In one example, such treatment may reduce the difference (or contrast) in chemical composition between the unexposed and exposed regions, and therefore a PEB operation is not performed. In another example, the exposed film may be thermally treated (e.g., at 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 stripper or positive-tone developer (e.g., a halide-based aqueous acid such as HCl, HBr, HI, or a combination thereof). In another example, the exposed film may be thermally treated (e.g., at low temperature) to further crosslink ligands within the EUV-unexposed portions of the resist, thereby providing EUV-exposed portions that can be selectively removed upon exposure to a stripper (e.g., a positive-tone developer). In yet another example, the PEB is omitted.

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

[0117] The dry development process may include a thermal (non-plasma) dry development process, a plasma dry development process, or a combination of a thermal dry development process and a plasma dry development process. In some embodiments, the dry development gas may include a halide-containing chemical (such as a hydrogen halide). Thus, the developer may include a hydrogen halide (e.g., HBr, HCl, etc.), a hydrogen and halogen gas (e.g., H2 and Cl2, H2 and Br2, etc.), boron trichloride, an organic halide, an acyl halide, a carbonyl halide, a thionyl halide, or a mixture thereof. The organic halide may be a C x H y F z , C x H y Cl z , C x H y Br z , and C x H y I z(where x, y, and z are values ​​greater than or equal to 0). Acyl halides may include, but are not limited to, CH3COF, CH3COCl, CH3COBr, and CH3COI. Carbonyl halides may include, but are not limited to, COF2, COCl2, COBr2, and COI2. Thionyl halides may include, but are 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 thermal treatment, a plasma treatment, or a combination of a thermal 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 a plasma is applied, the RF level may be adjusted to an RF power level of about 1000 W or less. The choice of development method along with optimization of development parameters can affect development selectivity, harshness, descumming, and other characteristics of development.

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

[0119] At block 114 of process 100, the photoresist undergoes a treatment prior to pattern transfer. The treatment may be a thermal treatment, a plasma treatment, a chemical treatment, a selective deposition treatment, or a combination of these treatments. The thermal treatment may expose the photoresist to an elevated 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 densify the photoresist and reduce LWR. In some embodiments, the plasma treatment may include passivation. The passivation may include a flash treatment including exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. In some embodiments, the plasma treatment may include curing. The curing may include exposure to a plasma of an inert gas and / or exposure to UV light. Chemical treatments may expose the photoresist to reactive species such as halide-based species (e.g., tungsten hexafluoride) or carbon-containing precursors (e.g., carbon monoxide, organometallic precursors) to improve etch resistance, reduce outgassing, and increase line CD. Selective deposition treatments may expose the photoresist to chemical precursors to selectively deposit a protective coating on the photoresist to reduce DtS, improve etch resistance, reduce outgassing, and increase line CD. Any one or more of the above treatments may be applied to the photoresist after development to improve the photoresist's performance during pattern transfer.

[0120] At block 116 of process 100, one or more substrate layers are etched using a photoresist mask for pattern transfer. Such substrate layers may be underneath the photoresist mask and removable by lithographic etching. The pattern transfer etch may etch material to a desired depth to form a plurality of patterned features. In some embodiments, the one or more substrate layers may be amorphous carbon (aC), 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). Any defects or CD variations in the photoresist mask will be reproduced in the patterned material during pattern transfer etching. Furthermore, poor etch resistance adversely affects the pattern transfer to the underlying substrate layer during etching. Post-development processing of the photoresist mask mitigates the above-mentioned issues to ensure successful pattern transfer during pattern transfer etching.

[0121] After pattern transfer, a post-etch inspection may be performed, and if necessary, rework may be performed by going back and repeating step 102.

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

[0123] In some embodiments, the substrate is a hard mask, which is used in lithographic etching of the underlying semiconductor material. Hard masks can be made of materials such as amorphous carbon (aC), tin oxide (e.g., SnO),x ), 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), 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., HfO), zirconium oxide (e.g., ZrO), and aluminum oxide (e.g., AlO). Suitable substrate materials include various carbon-based films (e.g., ashable hard masks (AHMs)), 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 any other film (typically a sacrificial film) applied to facilitate the patterning process. For example, the substrate is preferably SnO x (such as SnO2). In various embodiments, the layer may be 1 nm to 100 nm thick, or 2 nm to 10 nm thick.

[0124] In some embodiments, the substrate layer 204 comprises an ashable 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 organometallic-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 a PEB process. The photopatterned metal-containing EUV resist film 306 includes non-EUV exposed regions 206a and EUV exposed regions 206b.

[0125] As shown in FIG. 2B, the non-EUV-exposed regions 206 a of the photo-patterned metal-containing EUV resist film 206 are removed in a development process. Development may use a wet developer or a dry developer. If a dry developer is utilized, the dry development may proceed with or without igniting a plasma. In some embodiments, the dry developer may include a halide-containing chemical. A photoresist mask of the photo-patterned metal-containing EUV resist film 206 is formed by removal of the non-EUV-exposed regions 206 a after development. While FIGS. 2A-2C illustrate negative tone development, 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 the photoresist mask 208 to form recess features in the wafer 200 defined by the photoresist mask 208. The wafer 200 is subjected to a pattern transfer etch such that an etchant selectively removes the substrate layer 204 relative to the chemically modified photoresist mask 208. The pattern transfer etch may be performed by dry etching or wet etching. For example, the dry etch may utilize a fluorine-based plasma etch process or an oxygen-based plasma etch process. The pattern transfer etch 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 the increased line CD after the pattern transfer etch.

[0127] Returning to FIG. 1 , various steps of process 100 are traditionally performed in separate chambers and involve 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 treatment, are traditionally performed in separate chambers. Dry development may be performed in a dry development chamber (e.g., a thermal dry development chamber). Post-development treatment (post-develop bake) may be performed in a bake chamber. Optionally, a subsequent post-development treatment (line cure) may be performed in a UV chamber. This may lead to a longer queue time between dry development and post-dry development treatment. In some instances, this may potentially cause contamination to the backside of the wafer due to outgassing. To improve process efficiency and throughput and to limit potential contamination sources, the number of steps and / or chambers for various operations may be reduced by the methods disclosed herein.

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

[0129] The present disclosure relates to all-in-one dry development of photoresists. The dry development process may be performed in the same processing chamber. The dry development process and post-dry development process may be performed in the same processing chamber. A metal-containing photoresist or a metal oxide-containing photoresist may be wet- or dry-deposited. The metal-containing photoresist or the metal oxide-containing photoresist has high absorption of EUV radiation so that the photoresist can be patterned by EUV exposure to form exposed and unexposed regions. After the dry development selectively removes the exposed or unexposed regions of the photopatterned metal-containing photoresist or the 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: Reduced defects, reduced LWR, reduced DtS, reduced outgassing (e.g., tin outgassing), improved etch resistance, and increased line CD, thereby improving the performance of metal-containing or metal oxide-containing photoresists during etching.

[0130] Reference will now be made in detail to specific embodiments of the present disclosure. Examples of specific embodiments are illustrated in the accompanying drawings. While the present disclosure has been described in connection with these specific embodiments, it should be understood that it is not intended to limit the 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 provide a thorough understanding of the present disclosure. The present disclosure may be practiced without some or all of these specific details. Additionally, detailed descriptions of well-known process operations have been omitted to avoid unnecessarily obscuring the present disclosure.

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

[0132] Such EUV-sensitive films contain materials that undergo changes upon exposure to EUV, such as the loss of bulky pendant ligands attached to metal atoms. If the unexposed areas contain dense MOM-rich material, EUV-induced cleavage can provide intermediates that are more easily removed by positive-tone developers.

[0133] EUV patterning results in areas of the film with altered physical or chemical properties compared to unexposed regions. These properties can be exploited in subsequent processing, such as to dissolve either the unexposed or exposed regions, or to selectively deposit material in either the exposed or unexposed regions. 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 processing is carried out (it being understood that the hydrophilicity of the exposed and unexposed regions is relative to one another). For example, material removal may be achieved by exploiting differences in the film's chemical composition, density, and cross-linking. Removal may be by wet or dry processing, as further described herein.

[0134] The thickness of the EUV-patternable film formed on the surface of a substrate can vary depending on the surface characteristics, the material being utilized, and the process 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 EUV patterning conditions. For example, the total absorption of the resist film can 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 fully exposed. In some embodiments, the film thickness is 10 nm to 20 nm. Without limiting the mechanism, function, or utility of the present disclosure, it is believed that the processes of the present disclosure are applicable to a variety of substrates. Furthermore, as discussed above, the deposited film can closely conform to surface features, providing advantages in forming a mask on a substrate (such as a substrate with underlying features) without "filling" or otherwise planarizing such features.

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

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

[0137] In an example of a sequential CVD process, two or more gas streams of precursors and optional counter reactant sources are introduced into a deposition chamber of a CVD apparatus via separate inlets, where the gases mix and react in the vapor phase to form a coagulated polymer material or film on a substrate (e.g., by forming metal-oxygen-metal bonds). The gas streams may be introduced using, for example, separate inlets or a dual plenum showerhead. The apparatus is configured to allow the precursor and optional counter reactant flows to mix within the chamber, allowing the precursor and optional counter reactant to react to form a polymerized organometallic material or film (e.g., a metal oxide coating or a coagulated polymer material, such as by forming metal-oxygen-metal bonds).

[0138] To deposit metal oxides, CVD processes are typically performed at reduced pressures, such as between 0.1 Torr and 10 Torr. In some embodiments, the process is performed at a pressure between 1 Torr and 2 Torr. The temperature of the substrate is preferably lower than the temperature of the reactant stream. For example, the substrate temperature can be between 0°C and 250°C, or between ambient temperature (e.g., 23°C) and 150°C.

[0139] To deposit cohesive polymeric materials, CVD processes are typically performed at reduced pressures, such as 10 mTorr to 10 Torr. In some embodiments, processes are performed at 0.5 to 2 Torr. The substrate temperature is preferably equal to or less than the temperature of the reactant stream. For example, the substrate temperature can be between 0°C and 250°C, or between ambient temperature (e.g., 23°C) and 150°C. In various processes, deposition of polymerized organometallic materials onto a 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 products of such vapor-phase reactions have high molecular weights as metal atoms are crosslinked by counter reactants before condensing or otherwise depositing on the substrate. In various embodiments, the steric hindrance of bulky alkyl groups further inhibits the formation of a densely packed network, producing highly porous, low-density films.

[0140] A potential advantage of using dry deposition techniques is the ease of tailoring the film composition as it grows. In CVD processes, this may be achieved by varying the relative flow rates of the first and second precursors during deposition. Deposition can occur at temperatures between 30°C and 200°C and pressures between 0.01 Torr and 100 Torr (more commonly, about 0.1 Torr and 10 Torr).

[0141] Films (e.g., metal oxide coatings or aggregated polymer materials, such as by forming metal-oxygen-metal bonds) may also be deposited by ALD processes. For example, precursors and optional counter reactants are introduced at separate times representing ALD cycles. The precursors react on the surface to form up to a monolayer of material at a time during each cycle. This allows for excellent control of film thickness uniformity across the surface. ALD processes are typically performed at reduced pressures, such as 0.1 Torr to 10 Torr. In some embodiments, the process is performed at 1 Torr to 2 Torr. The substrate temperature may be between 0°C and 250°C, or between ambient temperature (e.g., 23°C) and 150°C. The process may be a thermal process or, preferably, a 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 can contain the same metal but different ligands. In another embodiment, the precursors can contain different metal groups. In one non-limiting example, alternating flows of various volatile precursors can provide mixed-metal-containing layers, such as utilizing a metal alkoxide precursor having a first metal (e.g., Sn) with a silyl-based precursor having a different second metal (e.g., Te).

[0143] The processes described herein can be used to achieve surface modification. Precursor vapors may be passed over the wafer in several iterations. The wafer may be heated to provide thermal energy for the reaction to proceed. During several iterations, heating may be between about 50°C and about 250°C. In some cases, pulses of precursors may be utilized, separated by pumping and / or purging steps. For example, a first precursor may be pulsed between pulses of a second precursor to induce ALD or ALD-like growth. In other cases, both precursors may be flowed simultaneously. Examples of elements useful for surface modification include I, F, Sn, Bi, Sb, Te, and oxides or alloys of these compounds.

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

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

[0146] Such underlying topographical features may include areas where material has been removed (e.g., by etching) or where material has been added (e.g., by deposition) during processing prior to performing the methods of the present technology. Such pre-processing may involve the methods of the present technology or other processing methods in an iterative process in which two or more layers of features are formed on a substrate. Without limiting the mechanism, function, or utility of the present disclosure, it is believed that in some embodiments the methods of the present disclosure provide advantages such as conforming the films of the present technology to underlying features without "filling" or otherwise planarizing such features, and the ability to deposit films on a variety of 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 exposed and unexposed regions of the photoresist film. The "exposed regions" may be understood as relatively "exposed regions," and the "unexposed regions" may be understood as relatively "unexposed regions." The exposure causes changes in chemical composition and crosslinking within the photoresist film, creating a contrast in etch selectivity ratios that can be utilized for subsequent development.

[0148] EUV exposure of the film can provide EUV-exposed regions with activated reactive centers containing metal atoms (M), which are generated by EUV-induced cleavage events. Such reactive centers can include dangling metal bonds, M-H groups, cleaved M-ligand groups, dimerized M-M bonds, or M-O-M bridges.

[0149] The EUV exposure may have a wavelength in the range of about 10 nm to about 20 nm (e.g., a wavelength of 10 nm to 15 nm (e.g., 13.5 nm)) in a vacuum atmosphere. In particular, patterning can provide EUV-exposed and non-EUV-exposed regions to form a pattern. In some embodiments, such patterning can have a wavelength of about 1 to 50 mJ / cm, 1 to 40 mJ / cm. 2 , 1-30mJ / cm 2 , 1-20mJ / cm 2 , or 1 to 10 mJ / cm 2 Includes radiation doses of

[0150] The present disclosure includes patterning using not only EUV but also DUV or electron beam radiation. In such patterning, radiation is focused onto one or more regions of the imaging layer. Exposure can be performed such that the imaging layer film includes one or more regions that are not exposed to radiation. The resulting imaging layer can include multiple exposed and unexposed regions to create a pattern consistent with the creation of transistors or other features of a semiconductor device formed by adding or removing material from the substrate during subsequent processing of the substrate. EUV, DUV, and electron beam radiation methods and apparatus useful herein include methods and apparatus well known in the art.

[0151] In some EUV lithography techniques, an organic hard mask (e.g., a PECVD amorphous hydrogenated carbon ashable hard mask) is patterned using a photoresist process. During photoresist exposure, EUV radiation is absorbed by the resist and the underlying substrate, generating high-energy photoelectrons (e.g., about 100 eV) and then a cascade of lower-energy secondary electrons (e.g., about 10 eV) that diffuse laterally a few nanometers. These electrons enhance the progression of chemical reactions in the resist that enhance EUV dose sensitivity. However, a secondary electron pattern, which is random in nature, is superimposed on the optical image. This unwanted secondary electron exposure causes reduced resolution, observable line-edge roughness (LER), and linewidth variations in the patterned resist. These defects are then carried over to the patterned material 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 used to form a thin film of a metal-containing film, such as a photosensitive metal salt or metal-containing organic compound (organometallic compound), that has a strong absorption in 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 photodecomposes upon EUV exposure to form a metal mask, which is a pattern transfer layer, during subsequent etching (e.g., in a conductor etching tool).

[0153] After deposition, the EUV-patternable thin film is patterned by exposure to a beam of EUV light, in some instances under a relatively high vacuum. The metal-containing film can then be deposited in a chamber integrated with a lithography platform (e.g., a wafer stepper) and transferred under vacuum to prevent reaction prior to exposure for EUV exposure. Integration with a lithography tool is facilitated by the fact that EUVL also requires very low pressures, given the strong optical absorption of incident photons by ambient gases (e.g., H2O, O2). In other embodiments, photosensitive metal film deposition and EUV exposure can be performed in the same chamber.

[0154] Photolithography processing can include one or more bake steps to promote the chemical reactions necessary to create the chemical contrast between exposed and unexposed areas of the photoresist. In high-volume manufacturing (HVM), such bake steps can be performed on a track where wafers are baked on a hotplate at a preset temperature under ambient air or possibly N2 flow. More careful control of the bake atmosphere, as well as the introduction of additional reactive gas components into the atmosphere during these bake steps, can help further reduce the required dose and / or improve pattern fidelity.

[0155] According to various aspects of the present disclosure, one or more post-treatments for metal and / or metal oxide-based photoresists after deposition (e.g., post-apply bake (PAB) or another post-apply treatment), and / or after exposure (e.g., post-exposure bake (PEB) (optionally omitted) or another post-exposure treatment), and / or after development (e.g., post-develop bake (PDB) or another post-development treatment) can increase the difference in material properties between exposed and unexposed photoresists, thus reducing dose-to-size (DtS), improving PR profiles, and improving line edge roughness and line width roughness (LER / LWR) after subsequent dry development. Such treatments can include thermal treatments with temperature, gas atmosphere, and humidity control to improve dry development performance 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] For post-application processing (e.g., PAB), thermal treatment can be used in conjunction with temperature (e.g., controlled by heating or cooling), gas atmosphere (e.g., air, HO, CO, CO, O, O, CH, CHOH, N, H, NH, NO, NO, Ar, He, or mixtures thereof) or vacuum, and humidity control to alter the composition of unexposed metal and / or metal oxide photoresists after deposition and before exposure. The alteration can increase the EUV sensitivity of the material, so that lower dose-to-size and edge roughness can be achieved after exposure and dry development.

[0157] For post-exposure processing (e.g., PEB), thermal treatment can be used with temperature, gas atmosphere (e.g., air, HO, CO, CO, O, O, CH, CHOH, N, H, NH, NO, NO, Ar, He, or mixtures thereof) or vacuum, and humidity control to change the composition of both the unexposed and exposed photoresist. The change can increase the difference in composition / material properties between the unexposed and exposed photoresist and the difference in the etch rate of dry development etch gases between the unexposed and exposed photoresist. This can achieve a higher etch selectivity. The improved selectivity can result in a more square PR profile with improved surface roughness and / or less photoresist residue / scum. In certain embodiments, PEB can be performed in air, optionally with water vapor and CO. In other embodiments, PEB may be omitted.

[0158] For post-development treatments (e.g., post-develop bake, or PDB), thermal treatments can be used in conjunction with temperature, gas atmosphere (e.g., air, HO, CO, CO, O, O, CH, CHOH, N, H, NH, NO, NO, Ar, He, or mixtures thereof) or under vacuum (e.g., with UV), and humidity control to alter the composition of the unexposed photoresist. In certain embodiments, the conditions further include the use of plasma (e.g., containing O, O, HO, Ar, He, or mixtures thereof). The alteration can increase the hardness of the material, which can be useful when the film is used as a resist mask when etching an underlying substrate.

[0159] In these cases, in another embodiment, the thermal treatment may be replaced with a remote plasma treatment to increase the reactive species, thereby lowering the energy barrier for the reaction and increasing productivity. Remote plasma generates more reactive radicals, which may allow the reaction temperature / time of the treatment to be reduced, leading to increased productivity.

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

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

[0162] In certain embodiments, the PAB and / or PEB processes may be performed at a gas atmosphere flow rate ranging from 100 sccm to 10,000 sccm, a humidity of a few percent 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, the PEB is omitted.

[0163] Depending on the selectivity requirements / constraints of a semiconductor processing operation, thermal treatments such as those described herein can be used to reduce the required EUV dose, or, where higher selectivity is required and higher doses can be tolerated, much higher selectivity (up to 100x selectivity of exposed to unexposed areas) can be obtained.

[0164] Still other steps may include in-situ measurements that can assess physical and structural features (e.g., critical dimensions, film thickness, etc.) during photolithography processing. Modules for achieving in-situ measurements include, for example, scatterometers, polarimetry, downstream mass spectrometry, and / or plasma-enhanced downstream optical emission spectroscopy modules.

[0165] A substrate may be provided to the process chamber, where the substrate is a semiconductor substrate having a substrate layer and a developed photoresist mask covering the substrate layer. The substrate layer may be beneath the developed photoresist mask and may comprise any suitable material to facilitate the patterning process. The substrate layer may be etched with high selectivity relative to the developed photoresist mask. In some embodiments, the one or more substrate layers may be made of a material such as spin-on carbon (SoC), spin-on glass (SOG), amorphous carbon (aC), 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 onto the substrate layer. The metal-containing photoresist may be provided as a positive-tone resist or a negative-tone resist having EUV-exposed and non-EUV-exposed regions after EUV exposure. After deposition, the metal-containing photoresist may be photopatterned in an EUV lithography chamber (scanner). After exposure and optional PEB treatment, the metal-containing photoresist may undergo development to selectively remove portions of the metal-containing photoresist (e.g., non-EUV-exposed 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 organometallic film. For example, the metal-containing EUV photoresist may contain Sn, O, and C atoms.

[0167] The processing chamber may provide an enclosed space for processing the substrate after development. The chamber walls of the processing chamber may be fabricated from 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 inorganic coating). The processing chamber may include a substrate support (e.g., a pedestal or 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. As such, 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 minimizing substrate transfer and reducing exposure to air breaks between operations. The processing chamber may include one or more heating elements for exposing the substrate to high temperatures. 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 delivering gas into the processing chamber. For example, the one or more gas lines may include a showerhead for supplying reactive gases toward the substrate in 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 transformer coupled plasma (TCP) reactor, or a capacitively coupled plasma (CCP) reactor. In some cases, the processing chamber further includes one or more gas outlets for evacuating gas, which may or may not be coupled to a vacuum pump for maintaining a desired pressure in the processing chamber.

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

[0169] The substrate layer is etched to form recess features using the developed metal-containing photoresist mask. This process may be referred to as pattern transfer or pattern transfer etching. The etching may 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 portions of the substrate layer exposed by the developed metal-containing photoresist mask. The metal-containing photoresist mask may define a pattern in which the features are to be etched. The features are etched into the substrate layer according to the pattern defined by the metal-containing photoresist mask. After post-development processing, the metal-containing photoresist mask may have increased line CD and / or improved etch resistance during the pattern transfer etch. The etched features 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 are not transferred to the features formed after the pattern transfer etch.

[0170] Heat Treatment In some embodiments, the substrate may be thermally treated by heating the substrate to an elevated temperature. This may also be referred to as a post-development bake (PDB). The thermal treatment of the substrate may serve to reduce defects and roughness from the metal-containing photoresist mask prior to pattern transfer etching. In particular, the thermal treatment of the substrate may improve chemical contrast in the metal-containing photoresist mask by removing scum. The thermal treatment of the substrate may harden the residue / scum and also reduce outgassing.

[0171] After wet or dry development, residue or scum can remain on the substrate. Residue or scum can remain in areas of the photoresist mask that was removed by development. Residue or scum can include residual etch by-products adsorbed on the surface of the substrate. For example, halogen vapors used in certain developers can react with moisture or oxygen to form residual etch by-products that are difficult to remove. Wet processing techniques often utilize moisture and / or oxygen, which can more easily lead to the formation of scum and residue. In some cases, residues can be formed from metal oxides (e.g., SnO) that can contribute to a loss of chemical contrast during pattern transfer and contaminate downstream processing tools. x ) may contain high metal concentrations or particles or clusters.

[0172] After wet or dry development, roughness can occur on the sidewalls of etched features in the developed pattern of the photoresist mask. Part of this can be due to stochastic or non-optimal Gaussian distribution of light, resulting in partially or fully exposed material in areas where the photoresist should remain unexposed, or vice versa. Additionally, scum formation on the sidewalls of etched features in the photoresist mask can exacerbate the roughness.

[0173] During the thermal treatment, the substrate may be heated to an elevated 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 the elevated temperature using one or more temperature-controllable elements in the process 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 the elevated 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 thermal treatment is performed using one or more inert gases. For example, the thermal treatment may be performed using a flow of nitrogen (N), helium (He), neon (Ne), argon (Ar), or xenon (Xe). In some embodiments, the thermal treatment is performed in air.

[0174] Higher temperatures in post-development thermal treatments can lead to increased descumming, reduced defects, and reduced roughness. However, higher temperatures can also lead to a decrease in line CD. It has been observed that higher temperatures during thermal annealing cause lateral shrinkage of the photoresist and a decrease in its height. A decreased line CD leads to a higher dose-to-size ratio. Post-development thermal treatments can present a trade-off between reduced defects and roughness and a higher dose-to-size ratio. This limits the thermal treatment to a desired temperature range and duration to optimize the benefits of reduced defects and roughness while minimizing the increase in dose-to-size ratio.

[0175] Plasma treatment In some embodiments, the substrate may be exposed to plasma for post-development treatment. The plasma treatment may function to densify and reduce roughness of the metal-containing photoresist mask prior to pattern transfer etching. In some cases, the plasma treatment may further improve 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 passivation and / or hardening effects.

[0176] The exposure to plasma may proceed by generating a plasma in a remote plasma generator or in a processing chamber where the substrate is being processed. One or more gases may be flowed into a plasma generation region, which may be a remote plasma generator or a processing chamber, and a plasma is ignited. The plasma generation chamber may be an inductively coupled plasma (ICP), transformer coupled plasma (TCP), or capacitively coupled plasma (CCP) reactor. Plasma energy is provided to activate the 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 (O), carbon dioxide (CO), carbon monoxide (CO), ozone (O), and sulfur dioxide (SO). Additionally or alternatively, the one or more gases may include halogen-containing species such as boron trichloride (BCl), silicon tetrachloride (SiCl), tin tetrachloride (SnCl), tungsten hexafluoride (WF), and difluoromethane (CHF). Additionally or alternatively, the one or more gases may include inert gas species such as nitrogen (N), helium (He), neon (Ne), argon (Ar), and xenon (Xe). Other gases 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 process conditions of the plasma treatment may be adjusted to achieve a desired result. Such process 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 flow rate of one or more gases. During operation, the plasma 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 a low plasma power and high ion energy. The directionality of the plasma may be controlled by a 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 for a duration of about 0.5 seconds to about 120 seconds, about 1 second to about 60 seconds, or about 2 seconds to about 40 seconds. The plasma treatment may adjust the plasma duty cycle during operation to achieve a desired result, where the RF power source may provide the plasma at any suitable duty cycle (e.g., about 1% to about 99%, or about 10% to 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, useful plasma processing systems may include radio frequency power amplifiers that can be continuously or pulsed.

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

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

[0182] In certain embodiments, the plasma treatment may be a continuous plasma dry development process. In this process, an inert gas, including but not limited to helium, argon, or a combination thereof, is co-flowed into the process chamber with about 1 to about 10 percent of a halogen-containing gas (e.g., HBr), and then a plasma is ignited at a voltage bias of about 40 volts to about 500 volts to descum. The flow rate of the halogen-containing gas may be about 200 to about 800 sccm. The plasma can be adjusted to remove scum from the photoresist surface by 1) ramping the TCP power from high to low, 2) maintaining a constant TCP power regardless of the pulsing bias, or 3) pulsing the bias and TCP simultaneously. The entire process 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. Indeed, certain reactive gas species may react with the metal-containing photoresist mask but 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 transformation 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 an 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 described in more detail below.

[0184] The reactive gas species may react with the metal-containing photoresist mask to increase line CD and decrease dose-to-size. The reactive gas species may react with the metal-containing photoresist mask to reduce 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). Furthermore, the reactive gas species may reduce outgassing, such as outgassing 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 etch resistance of the photoresist mask during subsequent etching operations. As an example, the reactive gas species may increase line CD and at least substantially maintain the high line CD of the photoresist mask after pattern transfer etching.

[0185] The reactive gas species may react more with the metal-containing photoresist than with the underlying substrate layer. In certain embodiments, the chemical treatment with the reactive gas species utilizes the chemistry of the EUV photoresist mask. The EUV photoresist mask may be comprised of an organometallic oxide film (e.g., an organotin oxide film) having Sn, O, and C atoms. The organotin oxide film may be comprised 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 reactive gas species may react with one or more elements of the organotin oxide film by oxidation, reduction, insertion, extraction, or other chemical reaction mechanism to induce a chemical change in the EUV photoresist mask. In some examples, the reactive gas species may include carbon monoxide (CO), where tin species may catalytically react with carbon monoxide. Without being limited by any theory, the compound SnOC x reacts with CO to form the new compound SnOC x (CO) y The chemical reaction induces changes in the EUV photoresist mask by widening the line CD. In some embodiments, the etch resistance of the new compound in the EUV photoresist mask is improved.

[0186] Reactive gas species other than CO may be used to induce chemical reactions in the EUV photoresist mask. Examples of useful reactive gas species may include, but are not limited to, air, water vapor (HO), hydrogen peroxide (HO), carbon dioxide (CO), oxygen (O), ozone (O), methane (CH), methanol (CHOH), ethanol (CHCHOH), nitrogen (N), hydrogen (H), ammonia (NH), nitrous oxide (NO), nitric oxide (NO), nitrogen dioxide (NO), acetylacetone (CHO), formic acid (CHO), acetic acid (CHCOOH), hydrogen cyanide (HCN), boron trichloride (BC1), silicon tetrachloride (SiCl), chlorine (Cl), boron (Br), hydrogen chloride (HCl), borohydride (HBr), hydrogen iodide (HI), hydrogen fluoride (HF), fluoromethane (CHF), difluoromethane (CHF), and combinations thereof. In some cases, the reactive 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 a combination thereof. Other reactive gas species may include metal precursors, such as tungsten hexafluoride (WF), tin tetrachloride (SnCl), molybdenum hexafluoride (MoF), molybdenum dioxide dichloride (MoOCl), and molybdenum pentachloride (MoCl). Other reactive gas species include tetrakis(dimethylamido)tin (Sn(N(CH))), tetrakis(dimethylamido)hafnium (Hf(N(CH)), dimethylaluminum ((CH)Al), trimethylaluminum ((CH)Al), titanium isopropoxide (Ti(OCH(CH)), tungsten carbonyl (W(CO). x )), molybdenum carbonyl (Mo(CO) x ), ruthenium carbonyl (Ru(CO) x ), iron carbonyl (Fe(CO) x), and combinations thereof. Thus, in some cases, the reactive gas species may include a metal halide or organometallic precursor (such as a metal carbonyl precursor). While conventional polymer-based photoresist materials may not react with metal halides or certain organometallic precursors, the metal-containing or metal oxide-containing photoresist materials of the present disclosure may be more prone to react with metal halides and organometallic precursors. Without being limited by any theory, when there is an M-OH bond in an organometallic photoresist, a MO-M' bridge may be formed, where M' is derived from the metal precursor (e.g., a metal halide or organometallic precursor).

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

[0188] In some embodiments, reactive gas species may be supplied to the processing chamber from a gas source fluidly connected to the processing chamber. The gas source (e.g., a gas storage tank) may be fluidly connected to the processing chamber via a gas supply line. The gas reactants may be premixed before entering the processing chamber or may be mixed upon entering the processing chamber. In some embodiments, 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 a 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 a metal-containing photoresist mask to induce a chemical change. The gas reactant may be a carbon-containing precursor that reacts with a metal chamber component to form an organometallic precursor. This reaction may be thermally driven to produce an organometallic precursor. For example, carbon monoxide supplied to the processing chamber may react with iron-containing chamber lines to form iron carbonyl (Fe(CO)), which readily reacts with an EUV photoresist mask. x ), which can increase the line CD of the EUV photoresist mask. Without being limited by any theory, iron carbonyl causes the deposition of iron oxide on the EUV photoresist mask. In another example, carbon monoxide or carbon dioxide supplied to the processing chamber reacts with tungsten-containing chamber lines (e.g., hot wires) to form tungsten carbonyl (W(CO)), which readily reacts with the EUV photoresist mask. x ) can be formed.

[0189] 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 a thermal treatment and a plasma treatment. While thermal or plasma treatment alone may present tradeoffs, such tradeoffs may be offset by further applying a chemical treatment to the metal-containing photoresist mask. Specifically, a chemical treatment may be combined with a thermal treatment such that one or more reactive gas species are flowed into the metal-containing photoresist mask at a high temperature. While a high temperature may reduce line CD, one or more reactive gas species may increase line CD in the metal-containing photoresist mask. In fact, the increase in line CD due to one or more reactive gas species may exceed the decrease in line CD due to a high temperature. This reduces defects and roughness in the metal-containing photoresist mask while reducing dose-to-size. In some embodiments, a chemical treatment may be combined with a plasma treatment such that radicals and / or ions of the reactive gas species are flowed into the metal-containing photoresist mask. The radicals and / or ions may increase the reactivity of the reactive gas species with the metal-containing photoresist mask. The metal-containing photoresist mask may be exposed to one or more reactive gas species in a plasma, which may change the chemical composition of the metal-containing photoresist mask and increase line CD and density. This may be done without necessarily worsening defects or roughness in the metal-containing photoresist mask. The plasma may be applied at a power that avoids damage to the substrate.

[0190] Inducing a surface or bulk reaction in a metal-containing photoresist mask can occur by applying energy to the reaction. Some energy from thermal and / or plasma exposure can be sufficient to induce a surface or bulk reaction. Therefore, process conditions (such as temperature and plasma power) can be adjusted to achieve a desired result. In some embodiments, the substrate temperature can 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 treatment with one or more reactive gas species. In some embodiments, the plasma power can be less than about 6 kW, between about 50W and about 4000W, between about 50W and about 1000W, or between about 100W and about 500W during chemical treatment with one or more reactive gas species.

[0191] Other process conditions (such as plasma frequency, exposure time, bias voltage, pressure, and flow rate) may be adjusted to facilitate chemical processing with one or more reactive 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 reactive gas species may be carried out for a duration of 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. A first reactive gas species may be flowed into the process chamber at a flow rate of 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 reactant 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 for a duration between about 20 seconds and about 5 minutes at a substrate temperature of about 240°C. The carbon monoxide may react with the EUV photoresist mask to change its chemical composition. In another example, tungsten hexafluoride may react with the EUV photoresist mask in place of carbon monoxide to change its chemical composition. The EUV photoresist mask may exhibit increased etch resistance during subsequent pattern transfer etching.

[0192] A particular embodiment of the disclosed method is shown in FIG. 3. The operations of process 300 may be performed in a different order and / or in different, fewer, or additional operations. One or more operations of process 300 may be performed using any of the apparatus described in 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 in FIG. 1 . The operation in 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, all performed in a single processing chamber. Operation 312 may be performed in place of operations 112 and 114 in FIG. 1 . Doing so may improve productivity and more effectively control defects, overlay, and CD. Consolidating all dry development and post-development operations into one processing chamber facilitates the reduction of metal outgassing (such as tin outgassing) without the need to add an additional step of a post-dry development bake, which is conventionally performed in a separate processing chamber.

[0194] Combining dry development and passivation or thermal dry development and plasma dry development in a single chamber is counterintuitive due to the opposing process conditions required by each operation, particularly with regard to pressure. They are traditionally performed in separate chambers with different processing tools to practically manage pressure requirements. Thermal processes require high pressure to achieve high etch rates. High partial pressures lead to better selectivity. Conversely, for plasma processes, low pressures are required to achieve anisotropic etching. When performed in a single processing chamber, pressure drops of several orders of magnitude must be achieved quickly, in about 1 to about 10 seconds. The use of throttle valves, dedicated pumps, multiple pumps, or process gas flow control can rapidly achieve pressure drops on the order of 10 seconds or less. In some embodiments, the pressure drop is achieved in 8, 7, 6, 5, 4, 3, or 2 seconds. The apparatus allows for maintaining one or more process parameters uniform, where the one or more process parameters include pumping, gas supply, or pumping and gas supply.

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

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

[0197] "Tin oxide" is used herein to refer to Sn, including integer values ​​of x and y as well as non-integer values ​​of x and y. x O y For example, "tin oxide" has the formula SnO n where 1≦n≦2, and n can be an integer or a non-integer value. "Tin oxide" refers to the substoichiometric compounds (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 crystalline and molecular structures. "Tin oxide" also includes amorphous tin oxide.

[0198] Examples of methods for performing the integrated operations of block 312 are described in further detail in Figures 4A, 4B, 4C, 4D, and 4E. The embodiments described in Figures 4A, 4B, 4C, 4D, and 4E are intended to be exemplary only and are not intended to limit the scope of block 312 of process 300. Figure 4A may describe an embodiment of block 312 in which dry development and passivation are performed in the same processing chamber. Figure 4B may describe an embodiment of block 312 in which thermal dry development and plasma dry development are performed in the same processing chamber. Figure 4C may describe an embodiment of block 312 in which dry development and curing are performed in the same processing chamber. Figure 4D may describe an embodiment of block 312 in which thermal dry development, plasma dry development, and passivation are performed in the same processing chamber. FIG. 4E may describe one embodiment of block 312 in which thermal dry development, plasma dry development, passivation, and curing are performed in the same processing chamber.

[0199] 4A is a flow chart of an example process 410 for performing dry development and passivation operations in the same processing chamber, according to certain disclosed embodiments. For some photoresists, under some processing conditions, only a thermal dry development process 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, dry development processes may be utilized to treat photoresist films. Non-limiting processes may include the use of halides such as hydrogen halides (e.g., HBr, HCl, etc.), hydrogen and halogen gases (e.g., H and Cl, H and Br, etc.), boron trichloride, organic halides, acyl halides, carbonyl halides, thionyl halides, or mixtures thereof. While this disclosure is not limited to any particular theory or mechanism of operation, it is understood that the approach utilizes the chemical reactivity of the EUV photoresist film with cleaning agents (e.g., HCl, HI, HBr, and / or BCl) to form volatile products using steam or plasma. Such volatile products may be removed by any method (e.g., by treatment with aqueous acid, as described herein). The EUV photoresist film may be removed at an etch rate of up to 1 nm / sec. Rapid removal of EUV photoresist films using these chemistries is applicable to chamber cleaning, backside cleaning, bevel edge cleaning, and PR development. Films can be removed using vapors at various temperatures (e.g., HCl or HBr above -20°C, or BCl3 above 50°C), but plasma may also be used to further accelerate or enhance reactivity.

[0201] The dry development process may include a thermal treatment, a plasma treatment, or a combination of a thermal treatment and a plasma treatment. The thermal treatment may expose the photoresist film to a process gas that may include one or more halides in a plasma-free process. 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. The thermal dry development and plasma dry development may be performed in the same process chamber in block 412. In negative tone development, the dry development process selectively removes less exposed areas of the photoresist film relative to more exposed areas of the photoresist film.

[0202] In some embodiments, the dry development is solely thermal dry development. Between blocks 412 and 414, flow path 413 may represent a change in process conditions to transition from dry development at block 412 to passivation at block 414. For example, flow path 413 may represent a pressure change made within the process chamber, such as a rapid pressure drop. The pressure drop may be achieved within the process chamber, allowing 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, multiple pumps, process gas flow control, 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 the dry development at block 412, the operation at block 414 represents a passivation step (e.g., a flash plasma treatment). The dry development at block 412 and the passivation at block 414 may be performed in the same process chamber. In some embodiments, the dry development at block 412 may be performed at a first pressure, and the 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 examples, the first pressure is in a range between about 5 mTorr and about 760 Torr, and the second pressure is in a range between about 5 mTorr and about 200 mTorr. In some examples, the pressure transition in the process chamber from the first pressure to the second pressure may occur in less than 10 seconds.

[0204] Passivation is useful when the photoresist has surface boron or chlorine substituents that can destabilize the photoresist. As used herein, "passivation" refers to a surface treatment that stabilizes the photoresist by forming a thin layer of stable film over the photoresist or by reducing volatile moieties on the photoresist. In some embodiments, if passivation is performed with an oxygen-containing plasma, the thin layer of stable film is an oxide, while in other embodiments, if passivation is performed with a hydrogen-containing or nitrogen-containing plasma, the volatile moieties may be removed. Surface smoothing may also be achieved during the operation of block 414. Plasma treatment may utilize equipment and techniques known to those skilled in the art, including transformer-coupled plasma (TCP), inductively coupled plasma (ICP), or capacitively coupled plasma (CCP). For example, treatment may be performed at a pressure of >0.5 mTorr (e.g., 1 mTorr to 100 mTorr) and 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) for 1 to 3000 seconds (e.g., 10 seconds to 600 seconds).

[0205] In some embodiments, the passivation is a treatment with an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. In some embodiments, the passivation is a treatment with an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. x H yThe passivation process may include a plasma treatment using HO, HO, SO, NO, NO, NO, NH, NH, or a mixture thereof, where x is an integer from 1 to 6 and y is an integer from 2 to 14. The gases may be introduced into the process chamber at a flow rate of about 100 to about 10,000 sccm. The passivation may be performed at a pressure of about 5 mTorr to about 500 mTorr. The passivation may be performed at a plasma power of about 50 W to about 300 W. The passivation may be performed for a process time of about 3 seconds to about 30 seconds. In some embodiments, the passivation is a flash process, where the flash process is performed at a relatively high speed for about 0.5 seconds to about 4 seconds, or about 0.5 seconds to about 10 seconds.

[0206] In some embodiments, passivation includes an O flush process at block 412, which supplies 1000 sccm to 2000 sccm of oxygen (O) flush gas to the process chamber. In certain embodiments, 100 W to 3,000 W of radio frequency power is supplied at 13.56 MHz to convert the flush gas into a plasma. A pressure of 20 mTorr to 100 mTorr is provided. This process may be referred to as an "O flush" operation because the power is supplied for a relatively short period of time (about 0.5 seconds to about 10 seconds, or about 0.5 seconds to about 10 seconds). 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 of 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 occurs after opening the process chamber. For backside and bevel edge cleaning processes, the vapor and / or plasma may be limited to specific areas of the wafer to ensure that only material on the backside and bevel edge is removed without causing any degradation of the film on the front side of the wafer. The photoresist film that is removed is typically composed of Sn, O, and C, but the same cleaning approach can be extended to films of other metal oxide resists and materials. Additionally, this approach can be used for film stripping and photoresist modification.

[0209] For wet cleaning, solutions include compounds such as tetramethylammonium hydroxide (TMAH), complexed amines such as ethylenediamine or diethylenetriamine, semi-aqueous fluoride strippers, or dilute hydrofluoric acid strippers. Metal oxides can be removed using acids, such as citric acid, acetic acid, octanoic acid, or other organic or inorganic acids. Additionally, hydrogen peroxide-containing acids may be used, such as very dilute (i.e., less than 0 / 1%) sulfuric acid / hydrogen peroxide mixtures. Combinations of any of the above wet cleaning agents may also be used.

[0210] FIG. 4B illustrates a process 420 for integrated thermal dry development and plasma dry development in a single process chamber, according to certain disclosed embodiments. The operation in block 422 is thermal dry development. Non-limiting processes can include the use of halides, such as hydrogen halides (e.g., HBr, HCl, etc.), hydrogen and halogen gases (e.g., H and Cl, H and Br, etc.), boron trichloride, organic halides, acyl halides, carbonyl halides, thionyl halides, or mixtures thereof. While this disclosure is not limited to any particular theory or mechanism of operation, it is understood that the approach utilizes the chemical reactivity of the EUV photoresist film with cleaning agents (e.g., HCl, HI, HBr, and / or BCl) to form volatile products. Such volatile products can be removed by any method (e.g., by treatment with aqueous acid, as described herein). The EUV photoresist film can be removed at an etch rate of up to 1 nm / sec. Rapid removal of EUV photoresist films using these chemistries is applicable to chamber cleaning, backside cleaning, bevel edge cleaning, and PR development. Films can be removed using vapors at various temperatures (e.g., HCl or HBr above -20°C, or BCl3 above 50°C).

[0211] In a 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 inorganic coating). One such coating is polytetrafluoroethylene (PTFE, e.g., Teflon™).

[0212] The thermal treatment may involve exposing the photoresist film to a process gas, which may include one or more halides, in a plasma-free process. In a thermal dry development process, the thermal dry development may be performed at a pressure of about 5 mTorr to about 760 Torr (e.g., about 300 mTorr). The temperature may be between about -60°C and about 120°C, or between about -20°C and about 60°C (e.g., about -10°C). The flow rate of the process gas in the thermal dry development process may be between about 10 sccm and about 10,000 sccm, or between about 100 sccm and about 3,000 sccm (e.g., about 500 sccm of HBr or HCl). The thermal dry development process may expose the substrate to the process gas for a time period of about 10 seconds to about 1 minute, depending on the photoresist film and its 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, flow path 423 may represent a change in process conditions to transition from thermal dry development at block 422 to plasma dry development at block 424. For example, flow path 423 may represent a pressure change made within the process chamber, such as a rapid pressure drop. The pressure drop may be achieved within the process chamber, allowing 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, multiple pumps, process gas flow control, 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 the thermal dry developing at block 422, the operation at block 424 represents plasma dry developing. The thermal dry developing at block 422 and the plasma dry developing at block 424 may be performed in the same processing chamber. In some embodiments, the thermal dry developing at block 422 may be performed at a first pressure, and the plasma dry developing at 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 a range between about 5 mTorr and about 760 Torr, and the second pressure is in a range between about 5 mTorr and about 200 mTorr. In some examples, transitioning the pressure in the processing chamber from the first pressure to the second pressure may occur within 10 seconds.

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

[0216] In some embodiments, the plasma dry development utilizes an inert carrier gas such as argon (Ar) or helium (He). In some embodiments, the 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, the plasma dry development utilizes at least one carbon-containing gas. For example, the carbon-containing gas may include methane (CH4). In some embodiments, the plasma dry development utilizes at least one hydrogen-containing gas. For example, the hydrogen-containing gas may include hydrogen gas (H2). In some embodiments, the 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, certain combinations of reactants may be advantageous for plasma dry development. Combinations may include, but are not limited to, HBr and N, HBr and H, HBr and Cl, HBr and HCl, HBr and BCl, BCl and Cl, BCl and HBr, BCl and CH, CH and Cl, CH, Cl, and N, CH and HCl, or CH and HBr. In some embodiments, the above combinations for plasma dry development in block 424 may be followed by thermal dry development in step 422 utilizing a hydrogen halide (such as HBr).

[0218] When the halide reactant flow is hydrogen gas and halide gas, remote plasma / UV radiation is used to generate radicals from H2 and Cl2 and / or Br2, and the hydrogen and halide radicals are flowed into the reaction chamber to contact the EUV photoresist on the wafer substrate layer. Suitable plasma power, without bias, can range from 100 W to 500 W. While 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 capabilities of the processing reactor. Although not shown in Figure 4B, it should be understood that post-development processing (such as passivation and / or hardening) may be performed in the same processing chamber as the thermal dry development and plasma dry development.

[0219] Act 426 is a pattern transfer process similar to that described for act 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. For backside and bevel edge cleaning processes, the vapor and / or plasma may be limited to specific areas of the wafer to ensure that only material on the backside and bevel edge is removed without causing any degradation of the film on the front side of the wafer. The EUV photoresist film being removed is typically composed of Sn, O, and C, but the same cleaning approach can be extended to films of other metal oxide resists and materials. Additionally, this approach can be used for film stripping and photoresist modification.

[0221] For wet cleaning, solutions include compounds such as tetramethylammonium hydroxide (TMAH), complexed amines such as ethylenediamine or diethylenetriamine, semi-aqueous fluoride strippers, or dilute hydrofluoric acid strippers. Metal oxides can be removed using acids, such as citric acid, acetic acid, octanoic acid, or other organic or inorganic acids. Additionally, hydrogen peroxide-containing acids may be used, such as very dilute (i.e., less than 0 / 1%) sulfuric acid / hydrogen peroxide mixtures. Combinations of any of the above wet cleaning agents may also be used.

[0222] 4C illustrates a process 430 for integrated dry development and curing in a single process chamber, according to certain disclosed embodiments. The operation at block 432 is thermal dry development. The operation at block 432 is similar to the operation described at block 422 in FIG. 4B.

[0223] Between blocks 432 and 434, flow path 433 may represent a change in process conditions to transition from thermal dry development at block 432 to plasma dry development and curing at block 434. Specifically, flow path 433 may represent a pressure change made within the process chamber, such as a rapid pressure drop. The pressure drop may be achieved within the process chamber, allowing 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, multiple pumps, process gas flow control, 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.

[0224] After the thermal dry developing at block 432, the operation at block 434 represents plasma dry developing and / or curing. In some cases, the operation at block 434 is only a curing step. In some other cases, the operation at block 434 is both a plasma dry developing and a curing step. The thermal dry developing at block 432 and the plasma dry developing and / or curing at block 434 may be performed in the same processing chamber. In some embodiments, the thermal dry developing at block 432 may be performed at a first pressure, and the plasma dry developing and curing at 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 is in a range between about 5 mTorr and about 760 Torr, and the second pressure is in a range between about 5 mTorr and about 200 mTorr. In some examples, transitioning the pressure in the processing chamber from the first pressure to the second pressure may occur within 10 seconds.

[0225] Aspects of the plasma dry development in block 434 are similar to those described in block 424 of Figure 4B. Aspects of the curing in block 434 are 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] In certain applications, it may be desirable to harden the photoresist. As used herein, "hardening" refers to a treatment of the surface and interior of the photoresist that concentrates material by processes such as crosslinking and / or scission of metal-carbon bonds in the photoresist. This may serve to increase the density of the photoresist material. In some examples, hardening may be achieved by treatment with a plasma of an inert gas. In one example, hardening by plasma treatment may include igniting a plasma to generate reactive species (e.g., ions and / or radicals) of argon, nitrogen, xenon, or helium. In some examples, hardening may be achieved by a flash treatment (e.g., an O2 flash treatment), which can perform both passivation and hardening. In certain embodiments, the pressure may be about 5 mTorr to about 500 mTorr, and the plasma power (e.g., TCP power) may be about 50 W to about 300 W. The gas flow rate may be about 100 sccm to about 1000 sccm at a process time of 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 about 10 W to about 1000 W and a pressure of 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 occur during or after plasma dry developing. In some embodiments, curing may occur without plasma dry developing.

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

[0230] Operation 438 is an optional cleaning process. The cleaning process in block 438 is similar to that described in block 428 of Figure 4B.

[0231] 4D illustrates a process 440 for integrated thermal dry development, plasma dry development, and passivation in a single process chamber in accordance with certain disclosed embodiments. The operation at block 442 is thermal dry development. The operation at block 442 is similar to the operation described at block 422 in FIG. 4B.

[0232] Between blocks 442 and 444, flow path 443 may represent a change in process conditions to transition from thermal dry development at block 442 to plasma dry development and passivation at block 444. In particular, flow path 443 may represent a pressure change made within the process chamber, such as a rapid pressure drop. The pressure drop may be achieved within the process chamber, allowing 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, multiple pumps, process gas flow control, 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.

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

[0234] Aspects of the plasma dry development in block 444 are similar to those described in block 424 of FIG. 4B. Aspects of the passivation in block 444 are similar to those described in block 414 of FIG. 4A. In some embodiments, the passivation is a plasma flash treatment, such as an O plasma flash treatment. Post-development treatments, such as passivation, may be performed in the same processing chamber as the thermal dry development in block 442. In some embodiments, passivation may occur during or after the plasma dry development.

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

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

[0237] 4E illustrates an alternative process 450 for dry developing, passivating, and curing all integrated into a single process chamber in accordance with certain disclosed embodiments. The operation at block 452 represents the thermal dry developing described above for block 422 in FIG. 4B.

[0238] Between blocks 452 and 454, flow path 453 represents a pressure change procedure that occurs within the processing chamber. As described above for flow path 453, the required pressure drop may be achieved within the processing chamber, allowing 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, multiple 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.

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

[0240] The plasma dry development and passivation are the same as those described above with reference to Figures 4A, 4B, 4C, and 4D, and the curing aspect was described above with reference to Figure 4C.

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

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

[0243] Operation 456 may be followed by an optional cleaning operation 458 similar to the operation described for block 428 of FIG. 4B above.

[0244] 5A-5E are schematic cross-sectional views illustrating various processing steps, including thermal dry development, plasma dry development, and passivation, according to certain disclosed embodiments, which may be performed in a single processing chamber.

[0245] 5A, 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 exposed regions 503 (or more exposed regions) and unexposed regions 505 (or less exposed regions). As shown in FIG. 5A, metal / metal oxide particles or clusters 507 may occupy the unexposed regions 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 progresses, the metal / metal oxide clusters 507 become more concentrated. The metal / metal oxide clusters 507 are generally difficult to remove. The thermal dry development may selectively remove the unexposed regions 505 over the exposed regions 503. Bulk removal of the unexposed regions 505 may be performed under the thermal dry development. The thermal dry development may be selective to the removal of organic materials. After bulk removal of the unexposed regions 505, the metal / metal oxide clusters 507 may remain as scum on the surface of the semiconductor substrate 501. In some embodiments, the thermal dry development may be performed by exposure to a halide (such as a hydrogen halide). As an example, the hydrogen halide may include HBr. In some embodiments, the thermal dry development may be performed in a process chamber at a first pressure, where the first pressure may be between about 5 mTorr and about 760 Torr. In some embodiments, the thermal dry development may be performed at a temperature between about -20°C and about 60°C, and the flow rate of the process gas may be between about 100 sccm and about 3000 sccm.

[0247] In FIG. 5C , the photoresist 510 is developed using a plasma dry development process in a processing chamber. As the plasma dry development progresses, the metal / metal oxide clusters 507 are removed. Furthermore, the plasma dry development may remove or substantially remove the remainder of the unexposed regions 505. In some embodiments, the plasma dry development may utilize a plasma of an inert gas species (such as He or Ar). In some embodiments, the plasma dry development may utilize a plasma of a halogen-containing species. 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 delivered in an inert carrier gas. In some embodiments, the plasma dry development may utilize 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 may include cyclical plasma dry development. In one example, the cyclical plasma dry development may alternate exposure to an inert gas plasma and a halogen-containing gas plasma. In some embodiments, the plasma dry development may include sequential plasma dry development. The continuous plasma dry development may be performed at variable power, constant power and pulse bias, or 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, specific combinations of reactants may be used in the 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 plasma dry development may be performed at a second pressure in the process chamber, where the second pressure may be between about 5 mTorr and about 200 mTorr.In some embodiments, the plasma dry development may be performed at a temperature between about -20°C and about 60°C, the process gas flow rate 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] 5D shows the photoresist 510 after plasma dry development. The metal / metal oxide clusters 507 have been removed, and the unexposed areas 505 of the photoresist 510 have been removed. In some embodiments, critical dimension (CD) loss 509 occurs as a result of plasma dry development. However, the directionality of the plasma dry development and other conditions associated with plasma dry development allow the metal / metal oxide clusters 507 to 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 photoresist 510 is shown after passivation. Passivation may be performed in the same processing chamber as the thermal dry development and plasma dry development. Passivation may be performed under the same pressure as the 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 oxide and / or nitride and / or carbon. In some embodiments, the passivation is a treatment with an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. For example, the passivation may be performed with a fluorine-containing plasma such as O2, O3, CO, CO2, H2, C x H y, HO, HO, SO, NO, NO, NO, NH, NH, or mixtures 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 O flash process, where the photoresist 510 is exposed to O plasma for a relatively fast time (e.g., about 0.5 seconds to about 4 seconds). Passivation may provide in-situ surface passivation to prevent outgassing of the photoresist 510. Passivation may additionally or alternatively perform hardening of the photoresist 510. Passivation may additionally or alternatively provide surface smoothing of the photoresist 510.

[0250] The foregoing description is merely exemplary in nature and is not intended to limit the disclosure, its applications, or uses. The broad teachings of the present disclosure may be embodied in a variety of forms. Accordingly, while the present disclosure includes specific examples, the true scope of the disclosure is not limited to those examples, as other variations will become apparent from a study of the drawings, the specification, and the following claims. It should be understood that one or more steps within a method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure. Furthermore, although each embodiment is described as having particular features, any one or more of the features described with respect to any embodiment of the present disclosure can be implemented in any of the other embodiments and / or combined with any of the features of the other embodiments, even if the combination is not expressly described. In other words, the above-described embodiments are not mutually exclusive, and substituting one or more embodiments for one another is within the scope of the present disclosure.

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

[0252] An apparatus configured for dry development, and in some cases for dry development and post-development treatment, includes a process chamber with a substrate support. The apparatus may include at least one reactive gas source in fluid communication with the process chamber. The apparatus may include one or more gas lines for supplying one or more gas species. In some embodiments, the one or more reactive gas species may include an organic gas species, an organometallic gas species, a metal-containing gas species, or a combination thereof. In some embodiments, the one or more reactive 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 a combination thereof. The one or more reactive gas species may be supplied to the process chamber via one or more gas lines to develop the photoresist and / or treat the post-development photoresist mask. The apparatus may include one or more heating elements for temperature control. Such heating elements may be provided within the process chamber and / or within the substrate support. Alternatively, such heating elements may be provided outside the process chamber. In some embodiments, the apparatus may include a plasma source for generating plasma during development and / or post-development photoresist mask processing. In some embodiments, the one or more reactive species may selectively deposit a protective film on the post-development photoresist mask. The apparatus may further include one or more sensors for sensing particle count, wafer count, thickness, or other parameters for triggering an endpoint of the post-development process.

[0253] 6 is a schematic diagram illustrating an example of a processing station for maintaining an environment suitable for performing photoresist developing and processing operations, 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 will be appreciated that multiple processing stations 600 may be included in a common processing tool environment. Furthermore, it will be appreciated that in some embodiments, one or more hardware parameters of processing station 600 (such as those described in more detail below) may be programmatically adjusted by one or more computer controllers.

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

[0255] The processing stations may be configured as modules within a cluster tool. Figure 9 illustrates a semiconductor processing cluster tool architecture with vacuum-integrated deposition and patterning modules suitable for implementing embodiments described herein. Such a cluster processing tool architecture may include resist deposition, resist exposure (EUV scanner), resist development, resist modification, and etch modules, as described above with reference to Figures 6 and 7 and further below.

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

[0257] 6 includes an optional vaporization point 603 for vaporizing the liquid reactant provided to the mixing vessel 604. In some embodiments, a liquid flow controller (LFC) may be provided upstream of the vaporization point 603 to control the mass flow rate of the liquid for vaporization and delivery to the processing station 600. For example, the LFC may include a thermal mass flow meter (MFM) disposed downstream of the LFC. A 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 process gases to the substrate 612. In the embodiment shown in Figure 6, the substrate 612 is positioned below the showerhead 606 and is shown on a pedestal 608. The showerhead 606 may have any suitable shape and may have any suitable number and arrangement of ports for distributing process gases to the substrate 612.

[0259] In some embodiments, the pedestal 608 may be raised or lowered to expose the substrate 612 to the space 607 between the substrate 612 and the showerhead 606. It will be appreciated 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 multiple plenum spaces with multiple temperature controls.

[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 temperatures greater than −20° C. and up to 300° C. (e.g., 50° C. to 280° C., such as about 100° C. to 240° C.) during development or post-development processing, as described in the disclosed embodiments. In some embodiments, the heater 610 of the pedestal 608 may include multiple independently controllable temperature control sections.

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

[0262] In some embodiments, the position of the showerhead 606 may be adjusted relative to the pedestal 608 to vary the spacing between the substrate 612 and the showerhead 606. Furthermore, it is understood that the vertical position 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 is understood that in some embodiments, one or more of these exemplary adjustments may be programmatically performed by one or more suitable computer controllers.

[0263] When a plasma is to be utilized, for example, during descumming, developing, processing, deposition, or smoothing operations, the showerhead 606 and pedestal 608 are in electrical communication with a radio frequency (RF) power source 614 and matching network 616 to power the plasma. In some embodiments, the plasma energy may be controlled by controlling one or more of the process station pressure, gas concentration, RF source power, RF source frequency, and plasma power pulse timing. For example, the RF power source 614 and matching network 616 may be operated at any suitable power to form a plasma having a desired composition of radical species. An example of a suitable power is 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 conditions for a process step may be included in a corresponding recipe step of a process recipe. In some examples, process recipe steps may be sequenced sequentially, such that all instructions for a process step are executed simultaneously with that process step. In some embodiments, instructions for setting one or more reactor parameters may be included in a recipe step. For example, a recipe step may include instructions for setting a flow rate of an etching gas (such as a hydrogen halide) and a time delay instruction for the recipe step. In some embodiments, the controller may include any of the features described below with respect to controller 750 of FIG. 7.

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

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

[0267] As described above, one or more processing stations may be included in a multi-station processing tool. FIG. 7 is a schematic diagram illustrating one embodiment of a multi-station processing tool 700 with an entry load lock 702 and an exit load lock 704, one or both of which may be equipped with a remote plasma source. A robot 706 at atmospheric pressure is configured to move wafers from a cassette loaded through a pod 708 into the entry load lock 702 through an atmospheric port 710. The wafer is placed on a pedestal 712 in the entry load lock 702 by the robot 706, the atmospheric port 710 is closed, and the load lock is pumped down. If the entry load lock 702 is equipped with a remote plasma source, the wafer may undergo a remote plasma treatment to treat the substrate surface within the load lock before being introduced into the processing chamber 714. Additionally, the wafer may be heated within the entry load lock 702, for example, to remove moisture and adsorbed gases. The chamber transfer port 716 to the processing chamber 714 is then opened and another robot (not shown) places the wafer into the reactor and onto the pedestal of the first station shown within the reactor for processing. While the example shown in Figure 7 includes a load lock, it will be appreciated that in some embodiments, the wafer may be placed directly into the processing station.

[0268] The illustrated processing chamber 714 includes four processing stations, numbered 1 through 4, in the embodiment shown in FIG. 7 . Each station includes a heated pedestal (designated 718 for station 1) and a gas line inlet. It is understood that in some embodiments, each processing station may have a different purpose or multiple purposes. For example, in some embodiments, a processing station may be switchable between a development mode and an etching processing mode. Additionally or alternatively, in some embodiments, processing chamber 714 may include one or more matched pairs of development and etching processing stations. While the illustrated processing chamber 714 includes four stations, it is understood that processing chambers according to the present disclosure may include any suitable number of stations. For example, in some embodiments, a processing chamber may include five or more stations, while in other embodiments, a processing chamber may include three or fewer stations.

[0269] FIG. 7 illustrates one embodiment of a wafer handling system 790 for moving wafers within a processing chamber 714. In some embodiments, the wafer handling system 790 may move wafers between various processing stations and / or between processing stations and load locks. It is understood that any suitable wafer handling system may be used. Non-limiting examples include a wafer carousel and a wafer handler robot. FIG. 7 also illustrates one embodiment of a controller 750 (e.g., a system controller) used to control the processing conditions and hardware status of the processing tool 700. The controller 750 may include one or more memory devices 756, one or more mass storage devices 754, and one or more processors 752. The processor 752 may include a CPU or 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 stored on 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 into the controller 750. For these purposes, application-specific integrated circuits, programmable logic devices (e.g., field-programmable gate arrays, or FPGAs), or the like may be used. Hereinafter, where "software" or "code" is used, functionally equivalent hard-coded logic may be used instead. The system control software 758 may comprise instructions for controlling the timing, mixture of gases, gas flow rates, chamber and / or station pressure, chamber and / or station temperature, wafer temperature, target power levels, RF power levels, substrate pedestal, chuck, and / or susceptor position, and other parameters of a particular process being performed by the processing tool 700. The system control software 758 may be configured in any suitable manner. For example, various process tool component subroutines or control objects may be written to control the operation of the process tool components used to perform the processes of the various process tools. The system control software 758 may be coded in any suitable computer-readable programming language.

[0271] In some embodiments, the system control software 758 may comprise input / output control (IOC) sequence instructions for controlling the various parameters described above. Other computer software and / or programs stored on the mass storage device 754 and / or memory device 756 associated with the controller 750 may also 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 comprise program code for processing tool components used to load a substrate onto the pedestal 718 and control the spacing between the substrate and other parts of the processing tool 700 .

[0273] The process gas control program may include code for controlling process gas composition and flow rates, and optionally for flowing gases into one or more process stations prior to deposition to stabilize the pressure in the process stations. The pressure control program may include code for controlling the pressure in the process stations, for example, by adjusting throttle valves in the exhaust systems of the process stations, gas flow rates to the process stations, etc.

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

[0275] A plasma control program may include code for setting RF power levels applied to process electrodes in one or more process stations according to embodiments herein.

[0276] The pressure control program may comprise code for maintaining pressure within the reaction chamber according to embodiments herein.

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

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

[0279] Signals for monitoring the process may be provided by analog and / or digital input connections of the controller 750 from various process tool sensors. Signals for controlling the process may be output at 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, etc. Appropriately programmed feedback and control algorithms may be used with data from these sensors to maintain process conditions.

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

[0281] Controller 750 typically includes one or more memory devices and one or more processors configured to execute instructions that cause the device to perform methods according to the disclosed embodiments. A machine-readable medium containing instructions for controlling processing operations according to the disclosed embodiments may be coupled to controller 750.

[0282] In some embodiments, the controller 750 is part of a system, which may be part of the examples described above. Such systems may include semiconductor processing equipment, 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 semiconductor wafers or substrates. The electronics may be referred to as a “controller” and may control various components or subcomponents of the system. Depending on the processing conditions and / or type of system, the controller 750 may be programmed to control any of the processes disclosed herein, such as 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 movement in and out of the tool and other transfer tools and / or load locks connected or coupled to the specific system.

[0283] Generally, the controller 750 may be defined as electronic equipment 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 chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), 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) that define operational parameters for performing specific processes on or for semiconductor wafers or instructions for the system. The operational parameters, in some embodiments, may be part of a recipe defined by a process engineer to accomplish one or more process steps during processing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0284] In some embodiments, the controller 750 may be part of or connected to a computer that is integrated with, connected to, or otherwise networked with the system, or a combination thereof. For example, the controller 750 may be in the “cloud” or may be all or part of a fab host computer system that can enable remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, or examine trends or performance indicators from multiple manufacturing operations, to change parameters of a current process, set up processing steps according to a current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system over a network (which may include a local network or the Internet). The remote computer may include a user interface that allows entry or programming of parameters and / or settings, which are communicated to the system from the remote computer. In some examples, the controller 750 receives instructions in the form of data, where the instructions specify parameters for each of the processing 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 as well as the type of tool that controller 750 is configured to interface with or control. Thus, as described above, controller 750 may be distributed, such as by having one or more separate controllers that are networked and operate toward a common purpose (such as the process and control described herein). One example of a distributed controller for such purposes is one or more integrated circuits on the chamber that communicate with one or more remotely located integrated circuits (e.g., located at the platform level or remotely as part of a remote computer) that cooperate to control the process in the chamber.

[0285] Without limitation, example systems may include a plasma etch 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 etch 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 etch (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, an EUV lithography chamber (scanner) or module, a development chamber or module, and any other semiconductor processing system that may be associated with or utilized in the processing and / or manufacturing of semiconductor wafers.

[0286] As described above, depending on the processing step or steps being 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 tools used in material transport to carry containers of wafers to or from tool locations and / or load ports within a semiconductor fabrication factory.

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

[0288] 8 is a schematic cross-sectional view of an inductively coupled plasma apparatus 800 suitable for performing certain embodiments or aspects of embodiments, such as dry development, post-development treatments (e.g., passivation and hardening), and / or etching. In other embodiments, other tools or tool types capable of performing the dry development, post-development treatments, 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 fabricated from stainless steel, aluminum, or plastic. The window 811 may be fabricated from quartz or other dielectric materials. An optional internal plasma grid 850 divides the overall processing chamber into an upper subchamber 802 and a lower subchamber 803. In most embodiments, the plasma grid 850 can be removed to utilize the chamber space formed by the subchambers 802 and 803. A chuck 817 is disposed within the lower subchamber 803 near the bottom inner surface. The chuck 817 is configured to receive and hold a semiconductor wafer 819 on which etching and deposition processes are performed. The chuck 817 may be an electrostatic chuck for supporting the wafer 819 when present. In some embodiments, an edge ring (not shown) surrounds the chuck 817 and has an upper surface that is approximately coplanar with the upper surface of the wafer 819 when the wafer is on the chuck 817. The chuck 817 also includes an electrostatic electrode for chucking and dechucking the wafer 819. A filter and DC clamp power supply (not shown) may be provided for this purpose. Other control systems for lifting the wafer 819 from the chuck 817 may also be provided. The chuck 817 may be charged using an RF power supply 823. The RF power supply 823 is connected to a matching network 821 through connection 827. The matching network 821 is connected to the chuck 817 through 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 50 V or a different bias power depending on the process being performed in accordance with the disclosed embodiments. For example, the bias power may be about 20V to about 100V, or about 30V to about 150V.

[0290] The elements for plasma generation include a coil 833 disposed above the window 811. In some embodiments, a coil is not utilized in the disclosed embodiments. The coil 833 is fabricated from a conductive material and includes at least one complete turn. The example coil 833 shown in FIG. 8 includes three turns. A cross section of the coil 833 is symbolized, with the "X" coil extending from the front to the back of the page and the "●" coil extending from the back to the front of the page. The elements for plasma generation also include an RF power supply 841 configured to provide RF power to the coil 833. Generally, the RF power supply 841 is connected to a matching network 839 through connection 845. The matching network 839 is connected to the coil 833 through connection 843. Thus, the RF power supply 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 apart relationship relative to the coil 833. In some embodiments, the Faraday shield 849 is positioned 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 apart relationship relative to the coil 833. For example, the Faraday shield 849 may be directly below the window 811 with no gap. The coil 833, the Faraday shield 849, and the window 811 are each configured to be substantially horizontal with respect to one another. The Faraday shield 849 may prevent metals or other species from depositing on the window 811 of the process chamber 824.

[0291] Process gases may be flowed into the processing chamber through one or more main gas inlets 860 and / or one or more side gas inlets 870 located in the upper subchamber 802. Similarly, although not explicitly shown, similar gas inlets may be used to supply process gases to the capacitively coupled plasma processing chamber. A vacuum pump (e.g., a one- or two-stage mechanical dry pump and / or turbomolecular pump) 840 may be used to draw process gases from the processing chamber 824 and maintain 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 and selectively control the application of a vacuum environment provided by the vacuum pump. This may be done using a closed-loop controlled flow restriction device, such as a throttle valve (not shown) or a pendulum valve (not shown), during operating plasma processing. Similarly, a vacuum pump and a valve-controlled fluid connection to the capacitively coupled plasma processing chamber may be used. A wide range of pressures adjusted within the processing chamber for integrated dry development and etching may be achieved with a variable speed vacuum system, a throttle valve, or by adjusting the flow rate of the processing gases, or by using two pressure regulation 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, process gases 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 with more complex gas inlets, such as one or more showerheads. The Faraday shield 849 and / or the optional grid 850 may include internal channels and holes that allow the supply of process gases to the process chamber 824. One or both of the Faraday shield 849 and the optional grid 850 may function as showerheads for the supply of process gases. In some embodiments, a liquid vaporization / delivery system may be located upstream of the process chamber 824 so that liquid reactants or precursors are vaporized and the vaporized reactants or precursors are introduced into the process chamber 824 via the gas inlets 860 and / or 870.

[0293] Radio frequency power is supplied from RF power supply 841 to coil 833, causing an RF current to flow through coil 833. The RF current flowing through coil 833 generates an electromagnetic field around coil 833. The electromagnetic field generates an induced current within upper subchamber 802. Physical and chemical interactions of the various ions and radicals generated with wafer 819 etch features in wafer 819 and selectively deposit layers on wafer 819.

[0294] When a plasma grid 850 is utilized such that both an upper subchamber 802 and a lower subchamber 803 are present, induced currents act 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 is an ion-ion plasma.

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

[0296] When installed in a clean room or manufacturing facility, the tool 800 may be connected to equipment (not shown) that includes plumbing to provide process gases, vacuum, temperature control, and environmental particle control. These equipment will be connected to the tool 800 when installed in the target manufacturing facility. Additionally, the tool 800 may be connected to a transfer chamber that allows semiconductor wafers to be transferred in and out of the tool 800 using robotic techniques, 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 process 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 the flow rate and duration when the disclosed embodiments are performed. 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, which may be part of the example described above. Various aspects of the controller 830 are 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 substrates are loaded and unloaded for deposition and etching as described herein. Alternatively, as described below, the EUVL patterning tool may be a module on a larger, multi-component tool.

[0300] 9 illustrates a semiconductor processing cluster tool architecture 900 with vacuum-integrated deposition, patterning, and processing modules coupled with a vacuum transfer module suitable for performing 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, patterning, and processing modules are vacuum-integrated according to the requirements of a particular process. Other modules, such as for etching, may also be included in the cluster.

[0301] A vacuum transfer module (VTM) 938 interfaces with 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 plasma-free thermal atomic layer deposition 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) connect with the VTM 938 and the patterning module 940. This tool architecture allows workpieces (such as semiconductor substrates or wafers) to be transferred under vacuum to prevent reaction prior to exposure. The integration of the deposition module with the lithography tool is facilitated by the fact that EUVL also requires very low pressures, given the strong optical absorption of incident photons by ambient gases (H2O, O2, etc.).

[0303] As noted above, this integrated architecture is just one possible example of a tool for performing the described processes. The processes may also be performed by more conventional stand-alone EUVL scanners and deposition reactors, either stand-alone or integrated as modules into a cluster architecture with other tools, such as etch, strip, etc., as described with reference to FIG. 9, except that there is no integrated patterning module.

[0304] Airlock 942 may be an "outgoing" load lock, referring to the removal of substrates from VTM 938, which feeds deposition module 920a, to patterning module 940, and airlock 946 may be an "incoming" load lock, referring to the return of substrates from patterning module 940 to VTM 938. Incoming airlock 946 may also provide an interface to the outside of the tool for accessing and unloading substrates. 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 (e.g., sensors 1-18 in the figure) are used to detect the passage of wafer 926 as it is moved between its respective stations. Patterning module 940 and airlocks 942 and 946 may similarly include additional facets and sensors not shown.

[0305] A main VTM robot 922 transfers wafers 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, each arm having an end effector 924 that grasps a wafer (such as wafer 926) for transfer. A front-end robot 944 is used to transfer wafers 926 from the output airlock 942 to the patterning module 940 and from the patterning module 940 to the input airlock 946. The front-end robot 944 may also transfer wafers 926 between the input load lock and the exterior of the tool for substrate access and removal. The input airlock module 946 can accommodate environments between atmosphere and vacuum, allowing wafers 926 to move between the two pressure environments without being damaged.

[0306] It should be noted 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 allow the substrate to degas before entering the patterning tool. The unload airlock 942 provides this function by holding the wafer to be transferred at a lower pressure (below the pressure in the patterning module 940) for a period of time and evacuating all off-gassing so that the optics of the patterning module 940 are not contaminated by off-gassing from the substrate. A suitable pressure for the unload 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 of the cluster structure, i.e., at a remote location within the manufacturing floor, and connected to the cluster structure via a network. The controller 950 may include one or more memory devices and one or more processors. The processor may include a central processing unit (CPU) or computer, analog and / or digital input / output connections, stepper motor controller boards, and other similar components. Instructions for implementing appropriate control operations are executed by the processor. These instructions may be stored in a memory device associated with the controller or provided over 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 extent of application of any aspect of 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 perform the various processing tool processes. 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 step of a semiconductor manufacturing process may comprise one or more instructions for execution by the controller. Instructions for setting process conditions for condensation, deposition, evaporation, patterning, and / or etching steps may be included in the corresponding recipe step, for example.

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

[0310] It should be noted that the computer controlling the wafer movement may be located locally to the cluster architecture, or may be located external to the cluster architecture, i.e., at a remote location within the manufacturing floor, and connected to the cluster architecture via a network. A controller such as that described above with respect to any of Figures 6, 7, or 8 may be implemented with the tool of Figure 9.

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

[0312] Conclusion Although the present embodiments have been described in some detail for purposes of clarity, it will be apparent that certain changes and modifications may be made within the scope of the appended claims. It should be noted that there are many other ways of implementing the processes, systems, and apparatus of the present invention. Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the embodiments are not limited to the details set forth herein.

Claims

1. 1. A method for performing dry development and passivation of a metal-containing photoresist all in one processing chamber, comprising: providing a patterned metal-containing photoresist on a semiconductor substrate in a processing chamber; thermally dry developing the patterned metal-containing photoresist with a process 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 different from or equal to the first pressure in the same processing chamber as the thermally dry developing of the patterned metal-containing photoresist to form a patterned substrate; A method comprising:

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

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

4. 10. The method of claim 1, wherein the passivating step comprises: ２ , O ３ , CO, CO ２ , H ２ , C ｘ H ｙ , H ２ O, H ２ O ２ , S.O. ２ , NO, NO ２ , N ２ O, N.H. ３ or a combination thereof, wherein x is an integer from 1 to 6 and y is an integer from 2 to 14.

5. 5. The method of claim 4, wherein the flashing process is performed for a duration of from about 0.5 to about 10 seconds.

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

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

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

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

10. 10. The method of claim 1, wherein said thermal dry developing comprises treatment with a halogen-containing gas.

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

12. 12. The method of claim 11, wherein the thermal dry developing and the plasma dry developing are alternately repeated.

13. 12. The method of claim 11, wherein the plasma dry developing is cyclic dry developing, direct plasma dry developing, remote plasma dry developing, or continuous plasma dry developing.

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

15. 12. The method of claim 11, wherein said plasma dry developing comprises treatment with a plasma of at least one halogen-containing gas in an inert carrier gas.

16. 16. The method of claim 15, wherein the halogen-containing gas is HBr, Br ２ , HCl, Cl ２ , H.I., I. ２ , or BCl ３ A method comprising:

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

18. 10. The method of claim 1, wherein the second pressure is the same as the first pressure.

19. 12. The method of claim 11, further comprising: 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; maintaining one or more process parameters uniform; A method comprising:

20. 10. The method of claim 1, further comprising curing the metal-containing photoresist after passivation in the same processing chamber used for the thermal dry developing.

21. 12. The method of claim 11, further comprising curing the metal-containing photoresist after passivation in the same processing chamber used for the thermal dry developing, plasma dry developing, and passivating.

22. 22. The method of claim 20 or 21, wherein the 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.

23. 1. An apparatus for performing dry development and passivation 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 in fluid communication with the pressure regulator; 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; Equipped with the at least one processor and the memory are communicatively coupled to each other; the at least one processor is at least operatively 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 passivation in the same processing chamber as the thermal dry development.

24. 24. The apparatus of claim 23, wherein the thermal dry development is performed at a first pressure and the passivation is performed at a second pressure less than or equal to the first pressure.

25. 24. The apparatus of claim 23, further comprising a photoresist thickness sensor module.

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

27. 24. The apparatus of 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 developing, wherein the plasma dry developing and the passivation are all performed within the same processing chamber.

28. 28. The apparatus of claim 27, wherein the plasma dry development is cyclical dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

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

30. 24. The apparatus of claim 23, wherein the passivation is treatment with an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

31. 24. The apparatus of claim 23, wherein the passivation is ２ , O ３ , CO, CO ２ , H ２ , C ｘ H ｙ , H ２ O, H ２ O ２ , S.O. ２ , NO, NO ２ , N ２ O, N.H. ３ , or a combination thereof, wherein x is an integer from 1 to 6 and y is an integer from 2 to 14.

32. 25. The apparatus of claim 24, wherein the second pressure is less than the first pressure.

33. 33. The apparatus of claim 32, further comprising: 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; An apparatus comprising computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to maintain uniformity of one or more process parameters.

34. 1. 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 in fluid communication with 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; Equipped with the at least one processor and the memory are communicatively coupled to each other; the at least one processor is at least operatively 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.

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

36. 35. The apparatus of claim 34, wherein the dry developing is performed at a first pressure and the passivating and curing are performed at a second pressure.

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

38. 35. The apparatus of claim 34, further comprising a photoresist thickness sensor module.

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

40. 35. The apparatus of claim 34, wherein the 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.

41. 35. The apparatus of claim 34, wherein the passivation is treatment with an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

42. 35. The apparatus of claim 34, wherein the passivation is ２ , O ３ , CO, CO ２ , H ２ , C ｘ H ｙ , H ２ O, H ２ O ２ , S.O. ２ , NO, NO ２ , N ２ O, N.H. ３ , or a combination thereof, wherein x is an integer from 1 to 6 and y is an integer from 2 to 14.

43. 36. The apparatus of claim 35, wherein the plasma dry development is cyclical dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

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

45. 35. The apparatus of claim 34, further comprising a UV exposure module.

46. 37. The apparatus of claim 36, wherein the second pressure is less than the first pressure.

47. 47. The apparatus of claim 46, further comprising: 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; An apparatus comprising computer-executable instructions for controlling the at least one processor to at least control the associated flow control hardware to maintain uniformity of one or more process parameters.

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

49. 49. The method of claim 48, wherein the thermal dry developing comprises exposure to a first process gas and the plasma dry developing comprises exposure to a plasma of a second process gas different from the first process gas.

50. 50. The method of claim 49, wherein the first process gas comprises a halogen-containing gas and the second process gas comprises an inert gas, a halogen-containing gas, or a combination thereof.

51. 51. The method of claim 50, wherein the first process gas comprises a hydrogen halide.

52. 49. The method of claim 48, wherein the thermal dry developing is performed at a first pressure and the plasma dry developing is performed at a second pressure different from the first pressure.

53. 49. The method of claim 48, wherein the thermal dry developing and the plasma dry developing are carried out at a temperature of about -20°C to about 50°C in the processing chamber.

54. 49. The method of claim 48, wherein the thermal dry developing and the plasma dry developing are alternately repeated.

55. 49. The method of claim 48, further comprising performing a dry development post-processing in the processing chamber.

56. 56. The method of claim 55, wherein the dry development post-treatment comprises passivating the metal-containing photoresist in the processing chamber.

57. 57. The method of claim 56, wherein the passivating comprises exposure to an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma.

58. 56. The method of claim 55, wherein the dry development post-treatment comprises hardening the metal-containing photoresist in the processing chamber.

59. 60. The method of claim 58, wherein the curing comprises 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.

60. 1. An apparatus for performing thermal and plasma dry development of metal-containing photoresists all within a single processing chamber, comprising: one or more processing chambers; one or more pressure regulators; one or more pumps in fluid communication with the pressure regulator; 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; Equipped with the at least one processor and the memory are communicatively coupled to each other; the at least one processor is at least operatively 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 to perform plasma dry development in the same processing chamber as the thermal dry development.

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