All-in-one dry developer 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 submitted simultaneously with this specification as part of this application. Each application for which this application claims benefit or priority as specified in the simultaneously submitted PCT request form is hereby incorporated by reference in its entirety for all purposes.

Background Art

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

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

[0004] However, EUV photolithography can present challenges such as low power output, light loss during patterning, and metal cross-contamination due to the emission of metallic gases. Therefore, improved EUV photoresist processing is still needed to more efficiently produce materials with desired properties.

[0005] The background art provided herein is intended to provide a general overview of the background to this disclosure. The works of the inventors named herein, to the extent described herein, are not considered prior art to this disclosure, either explicitly or implicitly, along with any manner of description that would not ordinarily be considered prior art at the time of filing. [Overview of the Initiative]

[0006] This disclosure relates to a method and apparatus for integrating a dry development process into the same processing chamber. In some embodiments, this disclosure relates to a method and apparatus for integrating dry development and dry development post-processing into the same processing chamber. This integration of processing the surface of a metal-containing photoresist improves throughput and reduces wafer handling, thereby improving the efficiency of semiconductor manufacturing by higher wafer productivity and better lithography control. The integrated process also improves the yield / defect performance of the device. Dry development post-processing includes passivation with plasma. Additionally or alternatively, dry development post-processing may include curing. Dry development post-processing, which involves plasma passivation and / or curing in a flash process, may be performed together with dry development in a single processing chamber, eliminating the need for dry development post-bake, which previously had to be performed in a separate chamber or tool. The integrated method also achieves surface smoothing and mitigates the release of contaminant gases through passivation.

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

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

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

[0010] In some embodiments, the flashing process is performed for a duration ranging from approximately 0.5 to approximately 10 seconds.

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

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

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

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

[0015] In some embodiments, the heat-dry developing process includes exposure to a halogen-containing gas.

[0016] In some embodiments, the method further comprises plasma dry development of a patterned metal-containing photoresist that has been heat-dry developed, wherein the heat-dry development, plasma dry development, and passivation are all performed in the same processing chamber.

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

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

[0019] In some embodiments, plasma dry development includes continuous plasma dry development, which is performed with variable power, constant power and pulsed bias, or variable power and pulsed bias.

[0020] In some embodiments, plasma dry developing includes exposure of the plasma to at least one halogen-containing gas in an inert transport 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 approximately 5 mTorr to 760 mTorr, and the second pressure is approximately 5 mTorr to 200 mTorr.

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

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

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

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

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

[0028] In a second embodiment, the disclosure includes an apparatus for performing dry development and passivation of a metal-containing photoresist all within a single processing chamber. In some embodiments, the apparatus comprises one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to 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 communicated with each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to 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 less than or equal to the first pressure.

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

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

[0031] In some embodiments, the apparatus further includes computer-executable instructions for controlling at least one processor to control at least the associated flow control hardware for performing plasma dry development, and 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, which is performed with variable power, constant power and pulsed bias, or variable power and pulsed bias.

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

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

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

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

[0038] In a third embodiment, the 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 comprises one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to 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 communicated with each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to control the associated flow control hardware to perform dry development in one of the processing chambers and to perform passivation and curing in the same processing chamber as the dry development. In some embodiments, dry development includes both thermal dry development and plasma dry development. In some embodiments, dry development is performed at a first pressure, and 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 includes a photoresist thickness sensor module.

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

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

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

[0043] In some embodiments, passivation involves O2, O3, CO, CO2, H2, C x H y This includes a flash treatment using 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, which is performed with variable power, constant power and pulsed bias, or variable power and pulsed bias.

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

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

[0048] In some embodiments, the apparatus further includes computer-executable instructions for controlling at least one processor to control at least associated flow control hardware in order to transition the pressure in the same processing chamber from a first pressure to a second pressure within 10 seconds, 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 maintain one or more processing parameters uniformly.

[0049] In a fourth embodiment, the disclosure includes a method for performing both thermal dry development and plasma dry development in a single processing chamber. In some embodiments, the method comprises the steps of: providing a metal-containing photoresist on a semiconductor substrate in a processing chamber; thermal 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, thermal dry development includes exposure to a first treatment gas, and plasma dry development includes exposure to a plasma of a second treatment gas different from the first treatment gas. In some embodiments, the first treatment gas includes a halogen-containing gas, and the second treatment gas includes an inert gas, a halogen-containing gas, or a combination thereof. In some embodiments, the first treatment gas includes a hydrogen halide.

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

[0052] In some embodiments, hot dry developing and plasma dry developing are performed in a processing chamber at a temperature of approximately -20°C to approximately 50°C.

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

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

[0055] In a fifth embodiment, the disclosure includes an apparatus for performing both thermal dry development and plasma dry development of a metal-containing photoresist in a single processing chamber. In some embodiments, the apparatus comprises one or more processing chambers, one or more pressure regulators, one or more pumps fluidly connected to the pressure regulators, a plasma processing system, one or more gas inlets to the processing 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 communicated with each other, the at least one processor is at least operably connected to the associated flow control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to 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 embodiments and other embodiments will be described further below with reference to the drawings. [Brief explanation of the drawing]

[0057] [Figure 1] A flowchart illustrating the processes for depositing, developing, and processing photoresist.

[0058] [Figure 2A] A schematic cross-sectional view showing various processing stages, including the development and processing of photoresist. [Figure 2B] A schematic cross-sectional view showing various processing stages, including the development and processing of photoresist. [Figure 2C] A schematic cross-sectional view showing various processing stages, including the development and processing of photoresist.

[0059] [Figure 3] A flowchart illustrating an example of an overall process, including the development of a photoresist in a single processing chamber, according to a specific disclosed embodiment.

[0060] [Figure 4A] A flowchart illustrating an example method for performing dry developing and passivation operations within the same processing chamber according to a specific disclosed embodiment.

[0061] [Figure 4B] A flowchart illustrating an example method for performing thermal dry development and plasma dry development operations within the same processing chamber according to a specific disclosed embodiment.

[0062] [Figure 4C] A flowchart illustrating an example method for performing dry developing and curing operations within the same processing chamber according to a specific disclosed embodiment.

[0063] [Figure 4D] A flowchart illustrating an example method for performing thermal dry development, plasma dry development, and passivation operations within the same processing chamber according to a specific disclosed embodiment.

[0064] [Figure 4E] A flowchart illustrating an example method for performing dry developing, passivation, and curing operations within the same processing chamber according to a specific disclosed embodiment.

[0065] [Figure 5A] A schematic cross-sectional view showing various processing steps, including thermal dry development, plasma dry development, and passivation, according to a specific disclosed embodiment. [Figure 5B] A schematic cross-sectional view showing various processing steps, including thermal dry development, plasma dry development, and passivation, according to a specific disclosed embodiment. [Figure 5C] A schematic cross-sectional view showing various processing steps, including thermal dry development, plasma dry development, and passivation, according to a specific disclosed embodiment. [Figure 5D] A schematic cross-sectional view showing various processing steps, including thermal dry development, plasma dry development, and passivation, according to a specific disclosed embodiment. [Figure 5E] A schematic cross-sectional view showing various processing steps, including thermal dry development, plasma dry development, and passivation, according to a specific disclosed embodiment.

[0066] [Figure 6] A schematic diagram showing an example of a processing station for maintaining an environment suitable for performing photoresist development operations and other photoresist processing operations according to a specific disclosed embodiment.

[0067] [Figure 7] A schematic diagram showing an example of a multi-station processing tool suitable for performing photoresist development operations and other photoresist processing operations according to a specific disclosed embodiment.

[0068] [Figure 8] A schematic cross-sectional view showing an example of an inductively coupled plasma apparatus for carrying out specific embodiments and operations described herein, according to certain disclosed embodiments.

[0069] [Figure 9]A diagram showing a semiconductor processing cluster tool architecture, comprising a vacuum-integrated deposition module and patterning module connected to a vacuum transfer module, suitable for performing the processing described herein, according to a specific disclosed embodiment. [Modes for carrying out the invention]

[0070] The following description includes numerous specific details to facilitate a full understanding of the embodiments presented. The disclosed embodiments can be implemented without some or all of these specific details. Furthermore, detailed descriptions of well-known processing operations have been omitted to avoid unnecessarily obscuring the disclosed embodiments. While the disclosed embodiments are described in relation to specific embodiments, it should be understood that there is no intention to limit the disclosed embodiments.

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

[0072] The term "formation of a mixed gas" generally refers to either or both of the following: mixing multiple gases before introducing them into a processing chamber, or mixing multiple gases within the processing chamber.

[0073] The term "inert gas" generally refers to a gaseous material that does not react with other chemicals in the 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 plasma formed at a processing station within a processing chamber. The term "remote plasma" generally refers to plasma formed at a location away from the 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 high-frequency power supply, an impedance-matched network, and one or more electrodes.

[0076] The term "precursor" generally refers to a chemical species adsorbed onto the substrate surface during ALD processing. The precursor reacts with the reactants to convert the adsorbed precursor into a film layer.

[0077] The term "processing chamber" or "processing chamber" generally refers to a container in which chemical and / or physical treatments are performed on a substrate. The pressure, substrate temperature, and atmospheric composition within the processing chamber may be controllable for performing the chemical and / or physical treatments.

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

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

[0080] The term "reactant" refers to the chemical species that react with precursors adsorbed on the substrate surface to form a film layer during ALD processing. The reaction between the reactant and the precursor can be accelerated by thermal energy and / or plasma in various processes.

[0081] As used herein, the term “semiconductor substrate” refers to a substrate at any stage in the manufacture of a semiconductor device that contains semiconductor material somewhere within its structure. It is understood that the semiconductor material within the semiconductor substrate does not need to be exposed. A semiconductor wafer having multiple layers of other material (e.g., dielectric) covering the semiconductor material is an example of a semiconductor substrate. In the detailed description below, it is assumed that the disclosed embodiments are carried out on a semiconductor wafer (e.g., a 200 mm, 300 mm, or 450 mm semiconductor wafer). However, the disclosed embodiments are not limited thereto. Workpieces may have a variety of shapes, sizes, and materials. In addition to semiconductor wafers, other workpieces on which the disclosed embodiments can be utilized include a variety of articles, such as printed circuit boards.

[0082] The embodiments disclosed below describe the deposition of materials onto substrates (such as wafers, substrates, or other workpieces). Workpieces may have a variety of shapes, sizes, and materials. In this application, the terms “semiconductor wafer,” “wafer,” “substrate,” “wafer substrate,” and “integrated circuit in progress” are used interchangeably. Those skilled in the art will understand that the term “integrated circuit in progress” may refer to a silicon wafer in the middle of any of the many stages of integrated circuit manufacturing. Wafers or substrates used in the semiconductor device industry typically have a diameter of 200 mm, 300 mm, or 450 mm. Unless otherwise specified, the processing details described herein (e.g., flow rate, power level, etc.) are suitable for processing 300 mm diameter substrates or for handling chambers configured to process 300 mm diameter substrates, and may be increased or decreased to suit other sizes of substrates or chambers. In addition to semiconductor wafers, other workpieces that can be used with the embodiments disclosed herein include a variety of articles, such as printed circuit boards. The processing 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 photosensitive materials used in processes (such as photolithography, photoetching, or photoengraving) for forming a patterned coating on a surface. A photoresist material changes its solubility in a developer when exposed to light of a specific wavelength. The photoresist layer can be composed of a positive-type (the exposed area becomes soluble) or negative-type (the exposed area becomes insoluble) photoresist material.

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

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

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

[0087] As used herein, the expression “A, B, and at least one of C” should be interpreted as meaning the logic (A or B or C) using the non-exclusive logic “or,” and not as meaning “at least one of A, at least one of B, and at least one of C.”

[0088] As used herein, the term “approximately” is understood to consider values ​​that are slightly greater than and / or less than the stated value, and that the variation does not significantly affect the desired function of the parameter outside the stated value. In some cases, “approximately” includes + / - 10% of any stated value. As used herein, this term modifies any stated value, range of values, or endpoints of one or more ranges.

[0089] As used herein, the terms “top,” “bottom,” “upper side,” “lower side,” “above,” and “below” are used to indicate the relative relationship between structures. The use of these terms does not indicate or require that a particular structure must be placed in a particular location within the apparatus.

[0090] Introduction and context This disclosure generally relates to the field of semiconductor processing. In particular, this disclosure is directed toward the development of photoresists such as metal-containing photoresists. Such metal-containing photoresists and / or metal oxide-containing photoresists may undergo either or both of the following: thermal dry development and / or plasma dry development. Such metal-containing photoresists and / or metal oxide-containing photoresists may undergo treatments to alter the chemical, physical, and / or optical properties of the photoresist after development and before pattern transfer. Treatment of photoresists improves the performance of the photoresist. For example, photoresist treatment can reduce dose-to-size (DtS), reduce LWR, increase line CD, improve etching resistance, increase throughput, reduce gas emissions of tin or other elements, and / or reduce defects / disconnections. Throughput can be increased by at least about 40%, 50%, about 60%, about 70%, about 80%, or about 90%.

[0091] Thin film patterning in semiconductor processing is often a crucial step in semiconductor manufacturing. Patterning includes lithography. In conventional photolithography (such as 193nm photolithography), a pattern is printed onto a photosensitive photoresist film by exposing a photoresist to photons in a selective area defined by a photomask. This triggers a chemical reaction in the exposed photoresist, creating a chemical contrast that can be used in the development process to remove specific parts of the photoresist and form a pattern. The patterned and developed photoresist film can then be used as an etching mask to transfer the pattern to an underlying film composed of metals, oxides, etc.

[0092] Advanced technology nodes (as defined by the International Semiconductor Technology Roadmap) include 22nm, 16nm, and beyond. For example, at the 16nm node, the width of vias or lines in damascene structures is typically around 30nm or less. Feature scaling in advanced semiconductor integrated circuits (ICs) and other devices is driving improvements in lithography resolution.

[0093] Extreme ultraviolet (EUV) lithography can extend lithography techniques by moving to imaging source wavelengths shorter than those achievable with conventional photolithography methods. EUV light sources with wavelengths of approximately 10–20 nm or 11–14 nm (e.g., 13.5 nm) can be used with 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 used for etching the underlying layer. The EUV resist may be a polymer-based chemically amplified resist (CAR) produced by liquid-based spin-on technology. Alternatives to CAR are metal oxide-containing films that can be directly photopatterned (such as those from Inpria, Corvallis, Oregon), which are described, for example, in U.S. Patent Publications US2017 / 0102612, US2016 / 0216606, and US2016 / 0116839, and are incorporated herein by reference, at least with respect to their disclosures relating to photopatternable metal oxide-containing films. Such films may be formed by spin-on technology or by dry deposition. Metal oxide-containing films can be patterned directly by EUV exposure in a vacuum atmosphere (i.e., without the use of a separate photoresist) to provide a patterning resolution of less than 30 nm, as described, for example, in U.S. Patent No. 9,996,004, issued June 12, 2018, “EUV PHOTOPATTERNING OF VAPOR-DEPOSITED METAL OXIDE-CONTAINING HARDMASKS,” and / or in International Application No. PCT / US19 / 31618, filed May 9, 2019, and published as International Publication No. WO2019 / 217749. At least their disclosures relating to the composition, deposition, and patterning of directly photopatternable metal oxide films for forming EUV resist masks are incorporated herein by reference. Generally, patterning involves exposing an EUV resist with EUV radiation to form a photopattern on the resist, and then developing it to form a mask by removing a portion of the resist according to the photopattern.

[0095] Directly photopatternable EUV or DUV resists may consist of, or contain, metals and / or metal oxides mixed within an organic component. The metals / metal oxides may promote EUV or DUV photon adsorption, generate secondary electrons, and / or exhibit high etching selectivity for the underlying film stack and device layers. These resists are developable using a wet (solvent) approach, which requires moving the wafer to a track where it is exposed to the developing solvent, dried, and then baked. Such resists may be developed using a dry approach or a combination of wet and dry approaches, as described herein.

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

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

[0098] Figure 1 is a flowchart of the steps of a conventional method for depositing, developing, and processing a photoresist. While the patterning process flow often refers to the EUV photosensitive resist in Figure 1, it should be understood that the process flow is not limited to EUV resists. The EUV resist may be any resist that is photosensitive to EUV radiation. The operations of process 100 may be performed in different orders and / or in different, fewer, or further operations. In some embodiments, the operations of process 100 may be performed, at least in part, according to software stored on one or more non-temporary computer-readable media.

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

[0100] A photoresist film can be deposited onto a substrate. Such a film can be deposited using wet or dry deposition processes, 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 deposition). While this disclosure often indicates that the metal-containing precursor is a tin-containing precursor, other metal atoms may be used.

[0101] The layers and films described herein are 1 × 10 7 cm 2The material may contain elements having a high light absorption cross-section, such as less than or equal to / mol (e.g., metallic or nonmetallic atoms). Such elements can 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 may contain one or more ligands (e.g., EUV-unstable ligands) that can be removed, cleaved, or crosslinked by radiation (e.g., EUV or DUV radiation).

[0103] The precursor may provide a radiation-sensitive, patternable film (or a patternable radiation-sensitive film or a photopatternable film). Such radiation may include EUV, DUV, or UV radiation that becomes patterned radiation when delivered by irradiation through a patterned mask. The film itself may be modified by exposure to such radiation so that the film becomes radiation-sensitive or photosensitive. In certain embodiments, the precursor is an organometallic compound and comprises 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 patterned radiation. For example, the precursor may contain ligands that react with a counter-reactant, thereby introducing a bond (e.g., an O-bond) between metal centers. In another example, the precursor may contain ligands that desorb in the presence of patterned radiation.

[0105] The precursor is a highly patterned radiation absorption cross-section (e.g., 1 x 10⁻⁶). 7 cm 2It may contain metals, metalloids, or atoms having an EUV absorption cross-section of 1 / mol or more. In some embodiments, M is tin (Sn), bismuth (Bi), tellurium (Te), cesium (Cs), antimony (Sb), indium (In), molybdenum (Mo), hafnium (Hf), iodine (I), zirconium (Zr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), silver (Ag), platinum (Pt), and lead (Pb).

[0106] In certain embodiments, the precursors include tin. Non-limiting tin precursors include SnF2, SnH4, SnBr4, SnCl4, SnI4, tetramethyltin (SnMe4), tetraethyltin (SnEt4), trimethyltin chloride (SnMe3Cl), dimethyltin dichloride (SnMe2Cl2), methyltin trichloride (SnMeCl3), tetraalyltin, tetravinyltin, hexaphenyltin(IV) (Ph3Sn-SnPh3, where Ph is phenyl), and dibutyldiphenyltin (SnBu2Ph 2) Trimethyl(phenyl)tin (SnMe3Ph), trimethyl(phenylethynyl)tin, tricyclohexyl tin 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) This includes (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-diazastannolysin-2-ylidene), or bis[bis(trimethylsilyl)amino]tin(Sn[N(SiMe3)2]2).

[0107] Examples of deposition techniques (for films, for example) include ALD (e.g., thermal ALD and plasma-enhanced ALD), PVD such as spin-coat deposition and PVD-simultaneous sputtering, CVD (e.g., PE-CVD or LP-CVD), sputter deposition, electron beam deposition including electron beam-simultaneous deposition, or any combination thereof (such as a combination of ALD and CVD components, or discontinuous ALD processes where precursors and reactants are separated in time or space).

[0108] Further descriptions of precursors applicable to this disclosure and methods for depositing them as EUV photoresist films can be found in International Application PCT / US19 / 31618, “METHODS FOR MAKING EUV PATTERNABLE HARD MASKS,” filed on 9 May 2019 and published as International Publication WO2019 / 217749. The thin films may contain optional materials in addition to the precursors and reactants to alter the chemical or physical properties of the film, such as changing the film’s sensitivity to EUV or increasing its etching resistance. Such optional materials may be introduced by doping, for example, before deposition on the substrate, during deposition on the substrate, and / or during vapor phase formation after deposition on the substrate. In some embodiments, a mild, distant H2 plasma may be introduced, for example, to replace some Sn-L bonds with Sn-H, thereby increasing the reactivity of the resist under EUV. In other embodiments, CO2 may be introduced to replace some Sn-O bonds with Sn-CO3 bonds, the latter of which may have greater resistance to wet development.

[0109] Various atoms present in the precursor and / or reactant may be provided within the capping layer, which is then placed on any beneficial layer or structure. The capping layer can be of any beneficial thickness (e.g., any thickness described herein, such as about 0.1 nm to about 5 nm).

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

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

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

[0113] In block 106 of process 100, post-coating bake (PAB) or post-coating treatment may be optionally performed. Such treatment may improve the etching resistance of the unexposed material to aqueous or non-aqueous solutions. In one example, such treatment may enhance the difference (or contrast) in chemical composition between the unexposed and exposed regions, and therefore the PAB operation is performed. In another example, such treatment may reduce the difference (or contrast) in chemical composition between the unexposed and exposed regions, and therefore the PAB operation is not performed. In yet another example, the use of PAB removes residual moisture from the film in order to form a cured resist film. PAB may include a combination of heat treatment, chemical exposure, and / or wetting to increase the EUV sensitivity of the film, thereby reducing the EUV dose for developing a pattern in the film. In certain embodiments, the PAB process is performed at a temperature higher than about 100°C, or at a temperature of about 100°C to about 200°C, or at about 100°C to about 250°C. In other embodiments, the PAB process is carried out at a temperature of about 190°C to about 350°C in the absence of oxygen-containing gas. In another example, the post-coating 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 within the film.

[0114] In 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 a contrast in etching selectivity that can be used to remove parts of the film. Such contrast can provide a positive tone resist. However, it is understood that EUV exposure can instead produce a contrast such that unexposed areas (or less exposed areas) are selectively removed. Such contrast can provide a negative tone resist, as described herein. The more exposed areas of the photoresist, with altered physical or chemical properties relative to the less exposed areas, are generated through photopatterning. The difference in properties between the more exposed and less exposed areas can be utilized in subsequent processing. EUV exposure may include exposure with wavelengths in the range of about 10 nm to about 20 nm (e.g., about 13.5 nm in a vacuum atmosphere), for example.

[0115] In 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, increase the contrast of the etching selectivity ratio of the exposed film, or post-process the film in any useful way. In one example, such processing may reduce the difference (or contrast) in chemical composition between the unexposed and exposed regions, and therefore the PEB operation is not performed. In another example, the exposed film may be heat-treated (e.g., at low temperatures and / or optionally in the presence of various chemical species) to promote the reactivity of the resist in the EUV-exposed or unexposed regions upon exposure to a stripping agent or positive-tone developer (e.g., halogenated aqueous acids such as HCl, HBr, HI, or combinations thereof). In yet another example, the exposed film may be heat-treated (e.g., at low temperatures) to further crosslink ligands in the EUV-unexposed regions of the resist, thereby providing EUV-exposed regions that can be selectively removed upon exposure to a stripping agent (e.g., a positive-tone developer). In yet another example, PEB is omitted.

[0116] In block 112 of process 100, the photoresist pattern is developed by positive-tone development or negative-tone development. In various embodiments of development, unexposed areas are selectively removed (to provide a pattern within the negative-tone resist). These steps may be wet-processed using one or more developers or developer 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, with optional 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] Dry developing processes may include thermal (without plasma) dry developing, plasma dry developing, or a combination of thermal and plasma dry developing. In some embodiments, the dry developing gas may contain a halide-containing chemical (such as hydrogen halide). Therefore, the developer may contain hydrogen halide (e.g., HBr, HCl, etc.), hydrogen and halogen gases (e.g., H2 and Cl2, H2 and Br2, etc.), boron trichloride, organic halides, acyl halides, carbonyl halides, thionyl halides, or mixtures thereof. Organic halides include C x H y F z , C x H y Cl z , C x H y Br z , and, C x H y I zThe following may be included, but are not limited to, values ​​of 0 or greater (where x, y, and z are 0 or greater). 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 developing gas may be flowed with or without an inert / carrier gas such as He, Ne, Ar, Xe, and N2. In some embodiments, dry developing may include heat treatment, plasma treatment, or a combination of heat treatment and 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 approximately -60°C and approximately 300°C. In some embodiments where plasma is applied, the RF level may be adjusted to an RF power level of approximately 1000W or less. The selection of the development method, along with the optimization of the development parameters, may affect the selectivity, roughness, discovering, and other characteristics of the development.

[0118] After block 112, a post-development inspection may be performed. If necessary, the process can be repeated by going back and repeating step 102.

[0119] In block 114 of process 100, the photoresist undergoes a treatment before pattern transfer. The treatment may be a heat treatment, plasma treatment, chemical treatment, selective deposition treatment, or a combination thereof. Heat treatment may involve exposing the photoresist to a high temperature between about 200°C and about 300°C to reduce defects and LWR. Plasma treatment may involve exposing the photoresist to a plasma, such as a direct (in-situ) plasma or a remote plasma, to increase the density of the photoresist and reduce LWR. In some embodiments, the plasma treatment may include passivation. Passivation may include a flash treatment 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. Curing may include exposure to a plasma with an inert gas and / or exposure to UV light. Chemical treatment may involve exposing the photoresist to reactive chemical species such as halogen compound species (e.g., tungsten hexafluoride) or carbon-containing precursors (e.g., carbon monoxide, organometallic precursors) to enhance etching resistance, reduce gas emissions, and increase line CD. Selective deposition treatment may involve exposing the photoresist to chemical precursors for selective deposition of a protective coating onto the photoresist to reduce DtS, improve etching resistance, reduce gas emissions, and increase line CD. Any one or more of the above treatments may be applied to the photoresist after development to improve the performance of the photoresist during pattern transfer.

[0120] In block 116 of process 100, one or more substrate layers are etched using a photoresist mask for pattern transfer. Such substrate layers are located beneath the photoresist mask and may be removable by lithographic etching. Pattern transfer etching may etch the material to a desired depth to form multiple patterned features. In some embodiments, one or more substrate layers are amorphous carbon (aC), amorphous silicon (a-Si), tin oxide (e.g., S n O x), silicon oxide (e.g., SiO2), silicon oxynitride (e.g., SiO2) x N y ), silicon oxycarbide (for example, 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 The photoresist mask may contain 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 are reproduced in the patterned material during pattern transfer etching. Furthermore, poor etching resistance negatively affects the transfer of the pattern to the underlying substrate layer during etching. Post-development treatment of the photoresist mask mitigates the above problems and ensures the success of pattern transfer during pattern transfer etching.

[0121] After pattern transfer, post-etching inspection may be performed. If necessary, the process can be repeated by going back to step 102.

[0122] Figures 2A to 2C are schematic cross-sectional views illustrating various processing steps, including the development and processing of a photoresist. As shown in Figure 2A, the wafer 200 comprises a substrate 202 and a substrate layer 204 to be etched. The patterning structure may include any useful substrate. For example, the input wafer may be prepared to have a substrate surface of a desired material, where the top layer is the layer onto which the resist pattern is transferred. The choice of material may vary depending on the integration, but generally, it is desirable to select a material that can be etched with a high selectivity ratio (i.e., much faster) 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. The hard mask is made of amorphous carbon (aC), tin oxide (e.g., SnOx ), silicon oxide (for example, SiO2, etc.) x ), silicon oxynitride (for example, SiO x N y ), silicon oxycarbide (for example, 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 The substrate material may include any of the following materials: ), hafnium oxide (e.g., HfO2), zirconium oxide (e.g., ZrO2), and aluminum oxide (e.g., Al2O3). Suitable substrate materials include various carbon-based films (e.g., ashable hard masks (AHMs)), silicon-based films (e.g., SiO2). x SiC x SiO x C y SiO x N y SiO x C y N z The substrate may include a-Si:H, polySi, or SiN, or any other film (generally a sacrificial film) applied to facilitate the patterning process. For example, the substrate is preferably SnO x It may contain (such as SnO2). In various embodiments, the layer may have a thickness of 1 nm to 100 nm, or 2 nm to 10 nm.

[0124] In some embodiments, the substrate layer 204 comprises an ashable hard mask such as amorphous carbon, spin-on carbon, or other material (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 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 the EUV scanner and / or after PEB processing. The photopatterned metal-containing EUV resist film 306 includes a non-EUV exposure region 206a and an EUV exposure region 206b.

[0125] As shown in Figure 2B, the non-EUV exposed regions 206a of the photopatterned metal-containing EUV resist film 206 are removed by a development process. Development may be performed using a wet or dry developer. If a dry developer is used, the dry development may proceed with or without plasma ignition. In some embodiments, the dry developer may contain a halide-containing chemical. The photoresist mask of the photopatterned metal-containing EUV resist film 206 is formed after development by the removal of the non-EUV exposed regions 206a. Figures 2A to 2C illustrate negative-tone development, but it should be understood that positive-tone development may be applied instead in this disclosure.

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

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

[0128] In particular, the efficiency of the conventional process 100 shown in Figure 1 can be improved by performing the process represented by block 112 together with the post-development process in the same processing chamber in a manner that eliminates the need for a separate chamber. Specifically, the efficiency of the process 100 shown in Figure 1 can be improved by performing the 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] This disclosure relates to an all-in-one dry development of a photoresist. The dry development process may be performed in the same processing chamber. The dry development process and dry development post-processing may be performed in the same processing chamber. A metal-containing photoresist or a metal oxide-containing photoresist may be wet-deposited or dry-deposited. The metal-containing photoresist or a metal oxide-containing photoresist has a high absorption capacity for EUV radiation so that the photoresist can be patterned by EUV exposure to form exposed and unexposed regions. After dry development selectively removes the exposed or unexposed regions of the photopatterned metal-containing photoresist or a 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) reaction 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 gas emissions (e.g., tin gas emissions), improved etching resistance, and increased line CD, thereby improving the performance of metal-containing or metal oxide-containing photoresists during etching.

[0130] This specification provides detailed references to specific embodiments of the Disclosure. Examples of specific embodiments are illustrated in the accompanying drawings. While this Disclosure is described in relation to these specific embodiments, it should be understood that it is not intended to limit the Disclosure to such specific embodiments. Rather, it is intended to cover alternatives, variations, and equivalents that may fall within the spirit and scope of this Disclosure. The following description provides numerous specific details to facilitate a full understanding of this Disclosure. This Disclosure can be implemented without some or all of these specific details. Also, detailed descriptions of well-known processing operations have been omitted to avoid unnecessarily obscuring this Disclosure.

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

[0132] Such EUV-sensitive films contain materials that undergo changes upon exposure to EUV, such as the loss of bulky pendant ligands bonded to metal atoms. If the unexposed areas contain high-density MOM-rich materials, an intermediate can be provided in which EUV-induced cleavage is more easily removed by a positive-tone developer.

[0133] EUV patterning creates areas of the film with altered physical or chemical properties compared to unexposed areas. These properties can be utilized in subsequent processes, such as to dissolve either the unexposed or exposed areas, or to selectively deposit material onto either the exposed or unexposed areas. In some embodiments, the unexposed film has a hydrophobic surface, and the exposed film has a hydrophilic surface under conditions under which such subsequent processes are performed (the hydrophilicity of the exposed and unexposed areas is recognized as relative to each other). For example, material removal may be performed by utilizing differences in the chemical composition, density, and crosslinking of the film. Removal may be by wet or dry processes, as further described herein.

[0134] The thickness of the EUV patternable film formed on the surface of the substrate may vary depending on the surface features, the materials used, and the processing conditions. In various embodiments, the film thickness may be in the range of about 0.5 nm to about 100 nm. Preferably, the film is thick enough to absorb most of the EUV light under EUV patterning conditions. For example, the total absorption rate of the resist film may be 30% or less (e.g., 10% or less or 5% or less) so that the resist material at the bottom of the resist film is sufficiently exposed. In some embodiments, the film thickness is 10 nm to 20 nm. Without limiting the mechanism, function, or usefulness of this disclosure, the processing of this disclosure is considered applicable to a variety of substrates. Furthermore, as described above, since the deposited film can closely match surface features, it offers advantages when forming a mask on a substrate (such as a substrate with underlying features) without "filling" or otherwise planarizing such features.

[0135] The film may consist of a metal oxide layer deposited by any useful method. Such a metal oxide layer may be deposited or coated using any EUV photosensitive material described herein, such as a precursor (e.g., a metal-containing precursor, a metal halide, a capping agent, or an organometallic agent), in combination with a reactant. In an example process, a polymerized organometallic material is formed in the gas 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 adhesive layer, or a capping layer.

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

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

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

[0139] To deposit aggregated polymer materials, CVD treatment is generally carried out under reduced pressure, such as 10 mTorr to 10 Torr. In some embodiments, the treatment is carried out at 0.5 to 2 Torr. The substrate temperature is preferably below the temperature of the reaction fluid. For example, the substrate temperature may be 0°C to 250°C, or ambient temperature (e.g., 23°C) to 150°C. In various treatments, the deposition of polymerized organometallic materials onto the substrate occurs at a rate inversely proportional to the surface temperature. Without limiting the mechanism, function, or usefulness of this disclosure, the products of such gas-phase reactions are thought to have a large molecular weight because the metal atoms are cross-linked with their reactants before condensing or otherwise depositing on the substrate. In various embodiments, the steric hindrance of bulky alkyl groups further inhibits the formation of densely packed networks, resulting in highly porous, low-density films.

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

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

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

[0143] The processes described herein are available for achieving surface modification. A precursor vapor may be passed over the wafer in several iterations. The wafer may be heated to provide thermal energy for the reaction to proceed. During the several iterations, the heating may be between approximately 50°C and approximately 250°C. In some examples, pulses of the precursor may be utilized and separated by pumping and / or purging steps. For example, a first precursor may be pulsed between pulses of a second precursor pulse to induce ALD growth or ALD-like growth. In other examples, both precursors may be passed 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 described herein can be used to deposit thin metal oxides or metals by ALD or CVD. An example is tin oxide (SnO x ), bismuth oxide (BiO x ), and Te are included. After deposition, the film is M as described elsewhere in this specification. a R b L c The substrate may be capped with an alkyl-substituted precursor in the form of . The reactant may be used to better remove the ligand, and multiple cycles may be repeated to ensure complete saturation of the substrate surface. The surface can then be prepared for deposition of an EUV photosensitive film. One possible method is SnO x This is a method for producing a thin film of [a certain material]. Possible chemical reactions include the growth of SnO2 by circulating tetrakis(dimethylamino)tin and a reactant (such as water or O2 plasma). After growth, a capping agent may be used. For example, isopropyltris(dimethylamino)tin vapor may be flowed over the surface.

[0145] The deposition process is applicable to any useful surface. As used herein, “surface” is a surface on which the film of the Technology is deposited or exposed to EUV during the process. Such a surface may be located on a substrate (e.g., on which the film is deposited) or on a film (e.g., on which a capping layer may be deposited).

[0146] Such underlying topographic features may include areas where material has been removed (e.g., by etching) or added (e.g., by vapor deposition) during processing before the method of this technique is implemented. Such pretreatment may include the method of this technique or other processing methods in an iterative process in which two or more feature layers are formed on a substrate. Without limiting the mechanisms, functions, or usefulness of the present disclosure, in some embodiments, the method of the present disclosure is thought to offer advantages such as matching the film of the technique to the underlying features without "filling" or otherwise planarizing such features, and the ability to vapor-deposit the film onto various material surfaces.

[0147] Exposure of metal-containing resist materials The photoresist film may be exposed to radiation. The photoresist film is exposed to radiation according to a desired pattern to form exposed and unexposed regions of the photoresist film. The “exposed region” may be understood as a relatively “exposed region,” and the “unexposed region” may be understood as a relatively “unexposed region.” Exposure causes changes in the chemical composition and crosslinking within the photoresist film, creating a contrast in etching selectivity ratios that can be used for subsequent development.

[0148] EUV exposure of a film can provide EUV-exposed regions having activated reaction centers containing metal atoms (M), which are generated by EUV cleavage events. Such reaction centers may include metal dangling bonds, MH groups, cleaved M-ligand groups, dimerized MM bonds, or MOM bridges.

[0149] EUV lithography may have wavelengths in the range of about 10 nm to about 20 nm (wavelengths 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 areas for forming a pattern. In some embodiments, such patterning has a flow rate of about 1 to 50 mJ / cm² and 1 to 40 mJ / cm². 2 , 1-30 mJ / cm 2 , 1-20 mJ / cm 2 , or 1-10 mJ / cm² 2 This includes the radiation dose.

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

[0151] In some EUV lithography techniques, organic hard masks (e.g., ashable hard masks of PECVD amorphous carbon hydride) are patterned using photoresist processing. During photoresist exposure, EUV radiation is absorbed by the resist and the underlying substrate, generating high-energy photoelectrons (e.g., approximately 100 eV), followed by a cascade of low-energy secondary electrons (e.g., approximately 10 eV) that diffuse laterally by a few nanometers. These electrons increase the rate of chemical reactions in the resist that enhance EUV dose sensitivity. However, the inherently random secondary electron pattern is superimposed onto the optical image. This undesirable secondary electron exposure results in reduced resolution, observable line edge roughness (LER), and linewidth variations in the patterned resist. These defects are carried over to the patterned material during subsequent pattern transfer etching.

[0152] In various embodiments described herein, vapor deposition (e.g., condensation) processes (e.g., ALD or MOCVD performed with a PECVD tool) may 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 effect on EUV (e.g., wavelengths on the order of 10 nm to 20 nm) at the wavelength of an EUVL light source (e.g., 13.5 nm = 91.8 eV). This film is photodegraded during EUV exposure to form a metal mask, which is a pattern transfer layer, during subsequent etching (e.g., in a conductive etching tool).

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

[0154] Photolithography processes may involve one or more bake steps to facilitate the chemical reactions necessary to create the chemical contrast between exposed and unexposed areas of the photoresist. In high-volume production (HVM), such bake steps may be performed on a track where the wafer is baked on a hot plate at a pre-set temperature under ambient air or possibly a stream of N2. More careful control of the bake atmosphere, along with 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 this disclosure, one or more post-treatments on metal and / or metal oxide-based photoresists after deposition (e.g., post-coating bake (PAB) or another post-coating treatment) and / or after exposure (e.g., post-exposure bake (PEB) (optional) or another post-exposure treatment) and / or after development (e.g., post-development bake (PDB) or another post-development treatment) can increase the difference in material properties between exposed and unexposed photoresists, and thus reduce dose-to-size (DtS), improve the PR profile, and improve line edge roughness and line width roughness (LER / LWR) after subsequent dry development. Such treatments, including heat treatment with control of temperature, gas atmosphere, and humidity, can improve the performance of dry development in subsequent treatments. In some examples, remote plasma may be used. However, in certain examples, PAB and / or PEB and / or PDB are not performed.

[0156] In post-coating treatment (e.g., PAB), the composition of the unexposed metal and / or metal oxide photoresist can be altered after deposition and before exposure by using heat treatment along with temperature control (e.g., by heating or cooling), gas atmosphere (e.g., air, H2O, CO2, CO, O2, O3, CH4, CH3OH, N2, H2, NH3, N2O, NO, Ar, He, or mixtures thereof), and humidity control. This alteration can increase the EUV sensitivity of the material, allowing lower dose-to-size and edge roughness to be achieved after exposure and dry development.

[0157] In the case of post-exposure treatment (e.g., PEB), the composition of both unexposed and exposed photoresists can be altered using heat treatment along with control of temperature, gas atmosphere (e.g., air, H2O, CO2, CO, O2, O3, CH4, CH3OH, N2, H2, NH3, N2O, NO, Ar, He, or mixtures thereof), or vacuum, as well as humidity. This alteration can increase the difference in composition / material properties between the unexposed and exposed photoresists, and the difference in the etching rate of the dry developer etching gas between the unexposed and exposed photoresists. This can thereby achieve a higher etching selectivity ratio. The improved selectivity ratio can result in a more square PR profile, along with improved surface roughness and / or less photoresist residue / scum. In certain embodiments, PEB may be performed in air, in the optional presence of water vapor and CO2. In other embodiments, PEB may be omitted.

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

[0159] In these cases, in other embodiments, heat treatment may be replaced with remote plasma treatment to increase the number of reactive species, thereby lowering the energy barrier for the reaction and increasing productivity. Remote plasma generates more reactive radicals, which can reduce the reaction temperature / time of the treatment, leading to increased productivity.

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

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

[0162] In certain embodiments, the PAB and / or PEB treatment may be performed with a gas atmosphere flow rate ranging from 100 sccm to 10,000 sccm, humidity from a few percent to a maximum of 100% (e.g., 20% to 50%), 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 the semiconductor processing operation, the required EUV dose can be reduced using the thermal treatment described herein. Alternatively, if a higher selectivity is required and a higher dose is acceptable, a much higher selectivity (up to 100 times the selectivity of exposed-area to unexposed-area areas) can be obtained.

[0164] Further steps may include in-situ measurements that allow for the evaluation of physical and structural features (e.g., critical dimensions, film thickness, etc.) during the photolithography process. Modules for implementing in-situ measurements include, for example, a scattermeter, deflection analysis, downstream mass spectrometry, and / or a plasma-enhanced downstream emission spectroscopy module.

[0165] A substrate may be provided to a processing chamber, where the substrate is a semiconductor substrate comprising a substrate layer and a post-development photoresist mask covering the substrate layer. The substrate layer may be located beneath the post-development photoresist mask and may contain any suitable material to facilitate patterning. The substrate layer can be etched with high selectivity relative to the post-development photoresist mask. In some embodiments, one or more substrate layers are 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 (for example, SiO x ), silicon oxynitride (for example, SiO x N y ), silicon oxycarbide (for example, 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., WO2) x ), may contain hafnium oxide (HfO2), zirconium oxide (e.g., ZrO2), or aluminum oxide (e.g., Al2O3).

[0166] The metal-containing photoresist may be dry-deposited or wet-deposited onto a substrate layer. The metal-containing photoresist may be provided as a positive-tone resist or a negative-tone resist having EUV-exposed and EUV-unexposed 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 be developed to selectively remove portions of the metal-containing photoresist (e.g., EUV-unexposed regions) 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 a sealed space for processing the substrate after development. The chamber walls of the processing chamber may be made of stainless steel, aluminum, plastic, or other suitable material. 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 back cleaning chamber, a PAB processing chamber, a PEB processing chamber, a development chamber, or an etching chamber. Thus, the processing chamber for post-development processing may be the same chamber used in a previous operation for photoresist processing, or the same chamber used in a subsequent operation for photoresist processing, thereby 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, one or more heating elements may comprise one or more infrared (IR) lamps or one or more light-emitting diodes (LEDs) positioned on a substrate support to control the temperature of the substrate. The processing chamber may comprise one or more gas lines for transporting gas into the processing chamber. For example, one or more gas lines may comprise showerheads for supplying reaction gas toward the substrate in the processing chamber. In some embodiments, the processing chamber may be a plasma generation chamber or may be coupled to a separate plasma generation chamber 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 may further comprise one or more gas outlets for exhausting gas, and the gas outlets may or may not be coupled to a vacuum pump for maintaining a desired pressure within the processing chamber.

[0168] The developed metal-containing photoresist mask is processed using one or more of the following operations: (i) thermal annealing of the developed metal-containing photoresist mask, (ii) exposure of the developed metal-containing photoresist mask to plasma, (iii) exposure of the developed metal-containing photoresist mask to one or more reaction gases, and (iv) selective deposition of a protective layer onto the developed metal-containing photoresist mask. The post-development treatment of the substrate may utilize one of the above-described thermal annealing, plasma treatment, chemical treatment, or selective deposition operations, or a combination thereof. Post-development treatment improves the performance of the metal-containing photoresist mask during pattern transfer etching. The above-described thermal annealing, plasma treatment, chemical treatment, and selective deposition techniques will be discussed in detail later.

[0169] The substrate layer is etched to form recessed features using a metal-containing photoresist mask after development. This process may be called pattern transfer or pattern transfer etching. Etching can selectively remove portions of the substrate layer without removing the metal-containing photoresist mask after development. Wet or dry etchants may be used to etch portions of the substrate layer exposed by the metal-containing photoresist mask after development. The metal-containing photoresist mask may define the pattern on which features are etched. 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 etching resistance during pattern transfer etching. 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, defects and roughness are not transferred to features formed after pattern transfer etching.

[0170] heat treatment In some embodiments, the substrate may be heat-treated by heating it to a high temperature. This may also be called post-development bake (PDB). Heat treatment of the substrate may serve to reduce defects and roughness from the metal-containing photoresist mask before pattern transfer etching. In particular, heat treatment of the substrate may improve the chemical contrast in the metal-containing photoresist mask by removing scum. Heat treatment of the substrate may harden residue / scum and reduce gas release.

[0171] After wet or dry development, residue or scum may remain on the substrate. This residue or scum may remain in areas of the photoresist mask removed by development. The residue or scum may include residual etching byproducts adsorbed onto the substrate surface. For example, halogen vapors used in certain developers can react with moisture or oxygen to form residual etching byproducts 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, the residue can contribute to the loss of chemical contrast during pattern transfer and contaminate downstream processing tools, such as metal oxides (e.g., SnO). x ) may contain high concentrations of metal or particles or clusters.

[0172] After wet or dry development, roughness may develop on the sidewalls of etched features in the developed pattern of the photoresist mask. Part of this can be due to the probabilistic nature of light or a suboptimal Gaussian distribution, resulting in areas where the material is partially or completely exposed, or vice versa, where the photoresist should remain unexposed. Furthermore, scum formation on the sidewalls of etched features in the photoresist mask can exacerbate roughness.

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

[0174] Higher temperatures in post-development heat treatment 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 and height shrinkage of the photoresist. Reduced line CD leads to a higher dose-to-size ratio. Post-development heat treatment can present a trade-off between defect and roughness reduction and a higher dose-to-size ratio. This requires limiting the heat treatment to a desired temperature range and duration to optimize the benefits of defect and roughness reduction 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. Plasma treatment may function to increase the density of the metal-containing photoresist mask and reduce roughness before pattern transfer etching. In some cases, plasma treatment may further improve the chemical contrast in the metal-containing photoresist mask by removing scum. Plasma treatment may use an inert gas species plasma or a reactive gas species plasma. Reactive gas species plasma may chemically react with the metal-containing photoresist mask or selectively deposit a protective film on the metal-containing photoresist mask. Plasma treatment may provide passivation and / or curing effects.

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

[0177] One or more gases may include oxygen-containing species such as oxygen (O2), carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), and sulfur dioxide (SO2). Additionally or alternatively, one or more gases may include halogen-containing species such as boron trichloride (BCl3), silicon tetrachloride (SiCl4), tin tetrachloride (SnCl4), tungsten hexafluoride (WF6), and difluoromethane (CH2F2). Additionally or alternatively, one or more gases may include inert gas species such as nitrogen (N2), 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 It may contain (methane (CH4), etc.). In some cases, the plasma may be an oxygen-based plasma, a nitrogen-based plasma, a hydrogen-based plasma, an inert gas plasma, and / or a carbon-based plasma. In some embodiments, the plasma is a remote plasma. In some other embodiments, the plasma is an in-situ plasma.

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

[0179] In some embodiments, a useful plasma processing system may include a high-frequency power amplifier that is capable of continuous or pulsed operation.

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

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

[0182] In certain embodiments, the plasma treatment may be continuous plasma dry development. In this treatment, an inert gas, including but not limited to helium, argon, or a combination thereof, is simultaneously flowed into the treatment chamber along with about 1 to about 10 percent halogen-containing gas (such as HBr), and then the plasma is ignited with a voltage bias of about 40 volts to about 500 volts to descam. 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 up the TCP power from high to low, 2) maintaining a constant TCP power regardless of the pulsed bias, or 3) pulse the bias and TCP simultaneously. The entire treatment may take about 7 to about 30 seconds in some embodiments. The pressure of the continuous dry development plasma treatment may be about 5 mTorr to about 50 mTorr.

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

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

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

[0186] Other reaction gas species besides 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 (H2O), hydrogen peroxide (H2O2), carbon dioxide (CO2), oxygen (O2), ozone (O3), methane (CH4), methanol (CH3OH), ethanol (CH3CH2OH), nitrogen (N2), hydrogen (H2), ammonia (NH3), nitrous oxide (N2O), nitrogen oxide (NO), nitrogen dioxide (NO2), acetylacetone (C5H8O2), formic acid (CH2O2), acetic acid (CH3COOH), hydrogen cyanide (HCN), boron trichloride (BCl3), silicon tetrachloride (SiCl4), chlorine (Cl2), boron (Br2), hydrogen chloride (HCl), hydrogen boride (HBr), hydrogen iodide (HI), hydrogen fluoride (HF), fluoromethane (CH3F), difluoromethane (CH2F2), and combinations thereof. In some cases, the reaction gas species may include oxygen-containing gases, carbon-containing gases, hydrogen-containing gases, nitrogen-containing gases, halogen-containing gases, or combinations thereof. Other reaction gas species may include metal precursors such as tungsten hexafluoride (WF6), tin tetrachloride (SnCl4), molybdenum hexafluoride (MoF6), molybdenum dioxide dichloride (MoO2Cl2), and molybdenum pentachloride (MoCl5). Other reaction gas species include tetrakis(dimethylamide)tin (Sn(N(CH3)2)4), tetrakis(dimethylamide)hafnium (Hf(N(CH3)2)4), dimethylaluminum ((CH3)2Al), trimethylaluminum ((CH3)3Al), titanium isopropoxide (Ti(OCH(CH3)2)4), and tungsten carbonyl (W(CO)). x )), molybdenum carbonyl (Mo(CO) x ), Ruthenium carbonyl (Ru(CO) x ), iron carbonyl (Fe(CO) x), and combinations thereof, may include metal-organic precursors. Thus, in some cases, the reaction gas species may include metal halides or organometallic precursors (such as metal carbonyl precursors). Conventional polymer-based photoresist materials cannot react with metal halides or certain organometallic precursors, but the metal-containing photoresist materials or metal oxide-containing photoresist materials of this disclosure may be more reactive with metal halides and organometallic precursors. Without being limited by any theory, if there is an M-OH bond in the organometallic photoresist, an MO-M' crosslink may be formed, where M' is derived from a metal precursor (e.g., a metal halide or organometallic precursor).

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

[0188] In some embodiments, the reaction 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 pre-mixed before entering the processing chamber, or they may be mixed when entering the processing chamber. In some embodiments, the reaction gas species may be generated in situ in the processing chamber. The gas reactants may react with each other to form reaction products that react with the metal-containing photoresist mask to induce a chemical change. Alternatively, the gas reactants may react with one or more chamber components (e.g., a metal chamber line) to form reaction products that react with the metal-containing photoresist mask to induce a chemical change. The gas reactants may be carbon-containing precursors that react with metal chamber components to form organometallic precursors. This reaction may be thermally driven to produce organometallic precursors. For example, carbon monoxide supplied to the processing chamber may react with an iron-containing chamber line to form iron carbonyl (Fe(CO)) which readily reacts with the EUV photoresist mask. x ) can form, thereby increasing the line CD of the EUV photoresist mask. Without being limited by any theory, iron carbonyls cause the deposition of iron oxide onto 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 readily react with tungsten carbonyl (W(CO)) on the EUV photoresist mask. x ) can form.

[0189] Chemical treatment of a metal-containing photoresist mask with one or more reactive gas species may be used in conjunction with either or both heat treatment and / or plasma treatment. While heat treatment or plasma treatment alone may exhibit trade-offs, such trade-offs can be offset by further applying chemical treatment to the metal-containing photoresist mask. Specifically, chemical treatment may be combined with heat treatment so that one or more reactive gas species are flowed into the metal-containing photoresist mask at a high temperature. High temperature can reduce line CD, but one or more reactive gas species can increase line CD within 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 high temperature. This reduces defects and roughness within the metal-containing photoresist mask while reducing dose-to-size. In some embodiments, chemical treatment may be combined with plasma treatment so that radicals and / or ions of the reactive gas species are flowed into the metal-containing photoresist mask. Radicals and / or ions can increase the reactivity between the reactive gas species and the metal-containing photoresist mask. The metal-containing photoresist mask may be exposed to one or more reactive gas species in the plasma, which can alter the chemical composition of the metal-containing photoresist mask and increase its line CD and density. This can be done without necessarily worsening the defects or roughness of the metal-containing photoresist mask. The plasma may be applied at a power level that avoids damage to the substrate.

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

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

[0192] Specific embodiments of the disclosed method are shown in Figure 3. The operations of process 300 may be performed in different orders and / or in different, fewer, or further operations. One or more operations of process 300 may be performed using the apparatus described in any of Figures 6 to 9. In some embodiments, the operations of process 300 may be performed, at least in part, according to software stored on one or more non-temporary computer-readable media.

[0193] In Figure 3, blocks 302-310 and 314 represent the same operations as blocks 102-110 and 116 in Figure 1. The operation in block 312 represents an integrated dry development operation, which may include thermal and plasma dry development, or may include dry development and post-development processing, all performed within a single processing chamber. Operation 312 can be performed instead of operations 112 and 114 in Figure 1. Doing so can improve productivity and allow for more effective control of defects, overlays, and CD. Integrating all dry development and post-development operations into a single processing chamber facilitates a reduction in metal gas emissions (such as tin gas emissions) without the need to add the additional step of dry development and baking, which is conventionally performed in a separate processing chamber.

[0194] The combination of dry development and passivation in a single chamber, or the combination of thermal dry development and plasma dry development, is counterintuitive, particularly in terms of pressure, due to the diametrically opposed processing conditions required for each operation. Conventionally, they are performed in different chambers with different processing tools to practically manage the pressure requirements. Thermal treatment requires high pressure to obtain high etching rates. High partial pressure leads to a better selectivity ratio. Conversely, for plasma treatment, low pressure is required to achieve anisotropic etching. When performed in a single processing chamber, a pressure drop of several orders of magnitude must be achieved rapidly, within approximately 1 to 10 seconds. The use of throttle valves, dedicated pumps, multiple pumps, or flow control of the processing gas can provide a rapid pressure drop on the order of 10 seconds or less. In some embodiments, the pressure drop is achieved in 8 seconds, 7 seconds, 6 seconds, 5 seconds, 4 seconds, 3 seconds, or 2 seconds. The apparatus enables the uniform maintenance of one or more processing parameters, where one or more processing parameters include pumping, gas supply, or pumping and gas supply.

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

[0196] When the metal-containing photoresist is a metal oxide (such as tin oxide), metal gas emission (such as tin gas emission) can be controlled without the need for baking after dry deposition.

[0197] "Tin oxide" in this specification includes integer values ​​of x and y, as well as non-integer values ​​of x and y. x O y It is considered to include everything that is stoichiometrically possible for it. For example, "tin oxide" has the chemical formula SnO n This includes compounds having , where 1 ≤ n ≤ 2, and n can be an integer or a non-integer value. "Tin oxide" is a quasi-stoichiometric compound (SnO 1.8This may include (etc.). "Tin oxide" also includes tin dioxide (SnO2 or stannous 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 operation 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 illustrative only and are not intended to limit the scope of block 312 of process 300. Figure 4A may describe one embodiment of block 312 in which dry development and passivation are performed in the same processing chamber. Figure 4B may describe one embodiment of block 312 in which thermal dry development and plasma dry development are performed in the same processing chamber. Figure 4C may describe one embodiment of block 312 in which dry development and curing are performed in the same processing chamber. Figure 4D may describe one embodiment of block 312 in which thermal dry development, plasma dry development, and passivation are performed in the same processing chamber. Figure 4E may illustrate one embodiment of block 312 in which hot dry development, plasma dry development, passivation, and curing are performed in the same processing chamber.

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

[0200] The operation of block 412 may be a dry developing process. As described herein, dry developing processes may be used to process 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., H2 and Cl2, H2 and Br2, 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, the approach is understood to utilize the chemical reactivity of the EUV photoresist film with a cleaning agent (e.g., HCl, HI, HBr, and / or BCl3) to form volatile products using vapor or plasma. Such volatile products may be removed by any means (e.g., by treatment with aqueous acid, as described herein). The EUV photoresist film may be removed at etching rates up to 1 nm / second. The rapid removal of EUV photoresist films through these chemical reactions is applicable to chamber cleaning, back cleaning, bevel edge cleaning, and PR development. The films can be removed using vapors at various temperatures (e.g., HCl or HBr at temperatures above -20°C, or BCl3 at temperatures above 50°C), but plasma may be used to further accelerate or enhance the reactivity.

[0201] Dry development may include heat treatment, plasma treatment, or a combination of heat treatment and plasma treatment. Heat treatment may involve exposing the photoresist film to a treatment gas that may contain one or more halides in a plasma-free treatment. Plasma treatment may involve exposing 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. Heat dry development and plasma dry development may be performed in the same processing chamber in block 412. In negative tone development, dry development selectively removes less exposed areas of the photoresist film from more exposed areas of the photoresist film.

[0202] In some embodiments, dry development is limited to hot dry development. Between blocks 412 and 414, the flow path 413 may represent a change in processing conditions for transitioning from dry development in block 412 to passivation in block 414. For example, the flow path 413 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, allowing both high-pressure and low-pressure processing to be performed in the same chamber. The pressure change may be controlled by a throttle valve, a dedicated pump, multiple pumps, flow rate control of the processing gas, or a combination of these techniques. If two or more pumps are used, one of the pumps may be a roughing pump and the other may be a turbopump. Optional purging with an inert gas may be performed before, after, or during the pressure drop operation.

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

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

[0205] In some embodiments, passivation is a process using an oxygen-containing plasma, a nitrogen-containing plasma, or a hydrogen-containing plasma. In some embodiments, passivation is performed using O2, O3, CO, CO2, H2, C x H yThe process includes plasma treatment using 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. The gas may be introduced into the processing chamber at a flow rate of approximately 100 to 10000 sccm. Passivation may be carried out at a pressure of approximately 5 mTorr to 500 mTorr. Passivation may be carried out with plasma power of approximately 50 W to 300 W. Passivation may be carried out with a process time of approximately 3 seconds to 30 seconds. In some embodiments, passivation is a flash treatment, which is carried out relatively quickly for approximately 0.5 seconds to 4 seconds, or approximately 0.5 seconds to 10 seconds.

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

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

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

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

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

[0211] In a heat-dry developing 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 heat treatment may involve exposing the photoresist film to a process gas that may contain one or more halides in a plasma-free treatment. In the hot dry development process, the hot 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 hot 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). Depending on the photoresist film and their composition and properties, the hot dry development process may involve exposing the substrate to the process gas for a time of about 10 seconds to about 1 minute. In some embodiments, the pressure is 400 to 500 mTorr for a duration of 10 to 20 seconds.

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

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

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

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

[0217] Under specific dry developing conditions, certain combinations of reactants may be advantageous for plasma dry developing. These 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 embodiments, the above combinations for plasma dry developing in block 424 may be followed by hot dry developing 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 come into contact with the EUV photoresist on the substrate layer of the wafer. Appropriate plasma power can be in the range of 100W to 500W without bias. While these conditions are suitable for some processing reactors, it should be understood that a wider range of processing conditions may be used depending on the performance of the processing reactor. Although not shown in Figure 4B, it should be understood that post-development processing (such as passivation and / or curing) may be performed in the same processing chamber as the thermal dry development and plasma dry development.

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

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

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

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

[0223] Between blocks 432 and 434, the flow path 433 may represent a change in processing conditions for transitioning from thermal dry development in block 432 to plasma dry development and curing in block 434. Specifically, the flow path 433 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, allowing both high-pressure and low-pressure processing to be performed in the same chamber. The pressure change may be controlled by a throttle valve, a dedicated pump, multiple pumps, flow rate control of the processing gas, or a combination of these techniques. If two or more pumps are used, one of the pumps may be a roughing pump and the other may be a turbopump. Optional purging with an inert gas may be performed before, after, or during the pressure drop operation.

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

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

[0226] For certain applications, curing of the photoresist is desirable. As used herein, “curing” means a surface and internal treatment of the photoresist that concentrates the material by treatment such as crosslinking and / or cleaving of the metal-carbon bonds of the photoresist. This can function to increase the density of the photoresist material. In some embodiments, curing may be achieved by treatment with an inert gas plasma. In one example, curing by plasma treatment may include plasma ignition to generate reactive species (e.g., ions and / or radicals) of argon, nitrogen, xenon, or helium. In some embodiments, curing may be achieved by flash treatment (e.g., O2 flash treatment), which can perform both passivation and curing. 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 for 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 an inert gas plasma and exposure to UV light.

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

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

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

[0231] Figure 4D shows an integrated thermal dry development, plasma dry development, and passivation process 440 in a single processing chamber according to a specific disclosed embodiment. The operation of block 442 is thermal dry development. The operation in block 442 is similar to the operation described in block 422 in Figure 4B.

[0232] Between blocks 442 and 444, the flow path 443 may represent a change in processing conditions for transitioning from thermal dry development in block 442 to plasma dry development and passivation in block 444. In particular, the flow path 443 may represent a change in pressure made within the processing chamber, such as a rapid pressure drop. The pressure drop may be achieved within the processing chamber, allowing both high-pressure and low-pressure processing to be performed in the same chamber. The pressure change may be controlled by a throttle valve, a dedicated pump, multiple pumps, flow rate control of the processing gas, or a combination of these techniques. If two or more pumps are used, one of the pumps may be a roughing pump and the other may be a turbopump. Optional purging with an inert gas may be performed before, after, or during the pressure drop operation.

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

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

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

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

[0237] Figure 4E shows an alternative process 450 for dry development, passivation, and curing, all integrated into a single processing chamber, according to a specific disclosed embodiment. The operation in block 452 represents the hot dry development described above for block 422 in Figure 4B.

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

[0239] Following the thermal dry development in block 452, the operations in block 454 represent plasma dry development, passivation, and curing, all of which can be performed within a single (same) processing chamber.

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

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

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

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

[0244] Figures 5A to 5E are schematic cross-sectional views illustrating various processing steps, including thermal dry development, plasma dry development, and passivation, according to a particular disclosed embodiment. The processing steps may be carried out in a single processing chamber.

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

[0246] In Figure 5B, the photoresist 510 is developed in a processing chamber using a hot-dry development process. As the hot-dry development progresses, the metal / metal oxide clusters 507 become more concentrated. The metal / metal oxide clusters 507 are generally difficult to remove. Hot-dry development can selectively remove the unexposed regions 505 rather than the exposed regions 503. Bulk removal of the unexposed regions 505 may be performed under hot-dry development. Hot-dry development can be selective for 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, hot-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 hot dry development may be carried out in a processing chamber at a first pressure, where the first pressure may be between about 5 mTorr and about 760 Torr. In some embodiments, the hot dry development may be carried out at a temperature between about -20°C and about 60°C, and the flow rate of the processing gas may be between about 100 sccm and about 3000 sccm.

[0247] In Figure 5C, the photoresist 510 is developed using a plasma dry development process in a processing chamber. As the plasma dry development progresses, metal / metal oxide clusters 507 are removed. Furthermore, the plasma dry development may remove or substantially remove the remaining unexposed areas 505. In some embodiments, the plasma dry development can utilize a plasma of an inert gas species (such as He or Ar). In some embodiments, the plasma dry development can utilize a plasma of a halogen-containing species. For example, halogen-containing gases may include HBr, HCl, HF, HI, Br2, Cl2, F2, I2, BCl3, or mixtures thereof. The halogen-containing gas may be supplied in an inert transport gas. In some embodiments, the plasma dry development may use a combination of plasma of an inert gas species and plasma of a halogen-containing gas. In some embodiments, the plasma dry development includes cyclic plasma dry development. In one example, cyclic plasma dry development may involve alternating exposure to inert gas plasma and halogen-containing gas plasma. In some embodiments, the plasma dry development includes continuous plasma dry development. Continuous plasma dry development may be performed with variable power, constant power and pulse bias, or variable power and pulse bias. In some embodiments, plasma dry development is used to remove scum from the surface of a semiconductor substrate 501. In some embodiments, specific combinations of reactants may be used in plasma dry development. 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 embodiments, plasma dry development may be performed in a processing chamber at a second pressure, which may be between about 5 mTorr and about 200 mTorr.In some embodiments, the plasma dry development may be performed at a temperature between approximately -20°C and approximately 60°C, the flow rate of the processing gas may be between approximately 100 sccm and approximately 3000 sccm, the TCP power may be between approximately 1W and approximately 500W, and the bias voltage may be between approximately 1V and approximately 300V.

[0248] Figure 5D shows the photoresist 510 after plasma dry development. 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, due to the orientation of the plasma dry development and other conditions associated with plasma dry development, the metal / metal oxide clusters 507 can be removed with minimal CD loss 509. Furthermore, plasma dry development may be used to improve line width roughness (LWR) performance.

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

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

[0251] Device The apparatus of this disclosure is configured for dry development of photoresist and, in some cases, also for post-development processing of photoresist masks. The apparatus may be configured for other processing operations, such as deposition, bevel and back cleaning, post-coating bake, EUV scanning, 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 comprise a single wafer chamber or multiple stations within the same processing chamber. In multiple stations within the same processing chamber, various processing operations, such as those described in this disclosure, may be performed at different stations within the same processing chamber. In some embodiments, the processing chamber for post-development processing of this disclosure may be the same chamber as development, the same chamber as pattern transfer etching, or the same chamber as both development and pattern transfer etching.

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

[0253] Figure 6 is a schematic diagram showing an example of a processing station for maintaining an environment suitable for performing photoresist development and photoresist processing operations, according to several embodiments. For simplicity, the processing station 600 is shown as a standalone processing station having a processing chamber body 602 to maintain a low-pressure environment. However, it can be seen that multiple processing stations 600 may be included in a common processing tool environment. Furthermore, in some embodiments, one or more hardware parameters of the processing station 600 (such as the parameters detailed below) may be programmatically adjusted by one or more computer controllers.

[0254] Multiple processing stations 600 may be provided within a common low-voltage 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 detailed below) may be programmatically adjusted by one or more computer controllers 750.

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

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

[0257] Figure 6 includes an optional vaporization point 603 for vaporizing the liquid reactant supplied 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 toward the vaporization and processing station 600. For example, the LFC may include a thermal mass flow meter (MFM) located downstream of the LFC. The plunger valve of the LFC may then be adjusted in response to a feedback control signal provided by a proportional-integral-derivative (PID) controller in electrical communication with the MFM.

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

[0259] In some embodiments, the pedestal 608 may be raised and lowered to expose the substrate 612 to the space 607 between the substrate 612 and the shower head 606. In some embodiments, the height of the pedestal may be programmatically adjusted by a suitable computer controller. In some embodiments, the shower head 606 may have multiple plenum spaces, each equipped with a temperature control unit.

[0260] In some embodiments, the pedestal 608 may be temperature-controlled using a heater 610. In some embodiments, the pedestal 608 may be heated to a temperature above -20°C and up to 300°C (e.g., 50°C to 280°C (approximately 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 a plurality of independently controllable temperature control sections.

[0261] Furthermore, 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 regulated by changing the flow rate of one or more gases introduced into the processing station 600.

[0262] In some embodiments, the position of the shower head 606 may be adjusted relative to the pedestal 608 to change the space between the substrate 612 and the shower head 606. Furthermore, the vertical position of the pedestal 608 and / or the shower head 606 may be changed by any suitable mechanism within the scope of this disclosure. In some embodiments, the pedestal 608 may include a pivot axis for rotating the orientation of the substrate 612. In some embodiments, one or more of these adjustments may be performed programmatically by one or more suitable computer controllers.

[0263] If the plasma may be used, for example, during discovering, developing, processing, deposition, or smoothing operations, the showerhead 606 and pedestal 608 electrically communicate with the radio frequency (RF) power supply 614 and the matching network 616 to power the plasma. In some embodiments, the plasma energy may be controlled by controlling one or more of the processing station pressure, gas concentration, RF source power, RF source frequency, and plasma power pulse timing. For example, the RF power supply 614 and the matching network 616 may be operated at any suitable power to form a plasma having radical species of a desired composition. 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 the conditions of a processing stage may be included in the corresponding recipe stage of the processing recipe. In some examples, the processing recipe stages may be arranged sequentially, so that all instructions for a processing stage are executed simultaneously with that processing stage. In some embodiments, instructions for setting one or more reactor parameters may be included in the recipe stage. For example, the recipe stage may include instructions for setting the flow rate of an etching gas (such as hydrogen halide) and a time delay instruction for the recipe stage. In some embodiments, the controller may have any of the features described later with respect to the controller 750 in Figure 7.

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

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

[0267] As described above, one or more processing stations may be included in the multi-station processing tool. Figure 7 is a schematic diagram showing one embodiment of a multi-station processing tool 700 with an inlet load lock 702 and an outlet load lock 704, one or both of which may be equipped with a remote plasma source. A robot 706 under atmospheric pressure is configured to move a wafer from a cassette loaded through a pod 708 into the inlet load lock 702 via an atmospheric port 710. Once the wafer is placed on a pedestal 712 in the inlet load lock 702 by the robot 706, the atmospheric port 710 is closed and the load lock is pumped evacuated. If the inlet load lock 702 is equipped with a remote plasma source, the wafer may undergo remote plasma treatment to treat the substrate surface within the load lock before being introduced into the processing chamber 714. Furthermore, the wafer may be heated within the inlet load lock 702, for example, to remove moisture and adsorbed gases. Next, the chamber transfer port 716 to the processing chamber 714 is opened, and another robot (not shown) loads the wafer into the reactor for processing and places it on the pedestal of the first station shown inside the reactor. The embodiment shown in Figure 7 includes a load lock, but it can be seen that in some embodiments the wafer may be loaded directly into the processing station.

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

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

[0270] In some embodiments, the controller 750 controls all operations of the processing tool 700. The controller 750 is stored in a mass storage device 754, loaded into a memory device 756, and runs system control software 758 executed by the processor 752. Alternatively, the control logic may be hardcoded into the controller 750. For these purposes, application-specific integrated circuits, programmable logic devices (e.g., field-programmable gate arrays, i.e., FPGAs) may be used. Wherever “software” or “code” is used below, functionally equivalent hardcoded logic may be used instead. The system control software 758 may include instructions for controlling timing, gas mixing, gas flow rate, chamber and / or station pressure, chamber and / or station temperature, wafer temperature, target power level, RF power level, substrate pedestal, chuck, and / or susceptor position, and other parameters of specific processing performed by the processing tool 700. The system control software 758 may be configured in any suitable way. For example, various processing tool component subroutines or control objects may be written to control the operation of processing tool components used to perform processing for various processing 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 include input / output control (IOC) sequence instructions for controlling the various parameters described above. Other computer software and / or programs stored in the mass storage device 754 and / or memory device 756 associated with the controller 750 may be used in some embodiments. Examples of programs or program sections for this purpose include a substrate positioning program, a processing gas control program, a pressure control program, a heater control program, and a plasma control program.

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

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

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

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

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

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

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

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

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

[0281] The controller 750 typically comprises one or more memory devices and one or more processors configured to execute instructions so that the device performs the method according to the embodiments of the disclosure. A machine-readable medium containing instructions for controlling processing operations according to the embodiments of the disclosure may be connected to the controller 750.

[0282] In some embodiments, the controller 750 is part of a system, and the system may be part of the examples described above. Such a system may comprise a semiconductor processing apparatus, including one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (such as a wafer pedestal, a gas flow system, etc.). These systems may be integrated with electronic equipment for controlling the operation of the system before, during, and after processing of semiconductor wafers or substrates. The electronic equipment may also be called a “controller,” and may control various components or sub-components of the system. Depending on the processing conditions and / or the type of system, the controller 750 may be programmed to control any of the processing disclosed herein, such as the supply of processing 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 operation settings, and wafer movement in and out of a load lock connected to or coupled with tools and other moving tools and / or specific systems.

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

[0284] In some embodiments, the controller 750 may be part of a computer integrated with the system, connected to the system, networked with the system in other ways, or a combination thereof, or connected to such a computer. For example, the controller 750 may be in the “cloud” or may be all or part of a fab host computer system that enables remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, or examine trends or performance metrics from multiple manufacturing operations, in order to change the parameters of the current operation, set up a processing step according to the current operation, or start a new operation. In some examples, a remote computer (e.g., a server) may provide processing recipes to the system via a network (which may include a local network or the internet). The remote computer may have a user interface that enables input or programming of parameters and / or settings, which are communicated from the remote computer to the system. In some examples, the controller 750 receives instructions in the form of data, which 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 processing to be performed and the type of tools that the controller 750 is configured to interface with or control. Thus, as described above, the controller 750 may be distributed, for example, by comprising one or more separate controllers that are networked and operate toward a common purpose (such as the processing and control described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on the chamber that communicate with one or more remotely located integrated circuits (located at the platform level, or as part of a remote computer, etc.) that cooperate to control the processing in the chamber.

[0285] Examples of systems, though not limited to them, may include plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, ALD chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, EUV lithography chambers (scanners) or modules, developing chambers or modules, and any other semiconductor processing systems related to or that may be used in the processing and / or manufacturing of semiconductor wafers.

[0286] As described above, depending on one or more processing steps performed by the tool, the controller 750 may communicate with one or more of the following: 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 for material transport to and from the tool locations and / or load ports within the semiconductor manufacturing plant.

[0287] In certain embodiments, ICP reactors that may be suitable for etching operations appropriate for the implementation of some embodiments are described here. Although ICP reactors are described in this specification, it should be understood that capacitively coupled plasma reactors may be used in some embodiments.

[0288] Figure 8 is a schematic cross-sectional view showing an inductively coupled plasma apparatus 800 suitable for carrying out a particular embodiment or aspect of an embodiment, such as dry development, post-development treatment (e.g., passivation and curing), and / or etching. In other embodiments, other tools or tool types having the capability to perform the dry development, post-development treatment, and / or etching processes described herein may be used for implementation.

[0289] The inductively coupled plasma apparatus 800 comprises a whole processing chamber 824 structurally defined by chamber walls 801 and a window 811. The chamber walls 801 may be made of stainless steel, aluminum, or plastic. The window 811 may be made of quartz or other dielectric material. An optional internal plasma grid 850 divides the whole processing chamber into an upper sub-chamber 802 and a lower sub-chamber 803. In most embodiments, the chamber space formed by the sub-chambers 802 and 803 can be utilized by removing the plasma grid 850. A chuck 817 is located near the bottom surface of the lower sub-chamber 803. 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 in the presence of the wafer. In some embodiments, an edge ring (not shown) surrounds the chuck 817 and has a top surface that is substantially coplanar with the top surface of the wafer 819 when the wafer is on the chuck 817. The chuck 817 also includes electrostatic electrodes for chucking and dechucking the wafer 819. A filter and a 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 circuit 821 through a connection 827. The matching circuit 821 is connected to the chuck 817 through a connection 825. Thus, the RF power supply 823 is connected to the chuck 817. In various embodiments, the bias power of the electrostatic chuck may be set to about 50V or to a different bias power, depending on the processing performed according to the disclosed embodiments. For example, the bias power may be approximately 20V to 100V, or approximately 30V to 150V.

[0290] The elements for plasma generation include a coil 833 positioned above the window 811. In some embodiments, the coil is not used in the disclosed embodiments. The coil 833 is manufactured from a conductive material and includes at least one complete winding. An example of a coil 833 shown in Figure 8 includes three windings. Cross-sections of the coil 833 are indicated by symbols, where the "X" coil rotates and extends from the front to the back of the paper, and the "●" coil rotates and extends from the back to the front of the paper. The elements for plasma generation also include an RF power supply 841 configured to supply RF power to the coil 833. Generally, the RF power supply 841 is connected to a matching circuit 839 through connection 845. The matching circuit 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 positioned between the coil 833 and the window 811. The Faraday shield 849 may be maintained in a spaced-out position relative to the coil 833. In some embodiments, the Faraday shield 849 is located directly above the window 811. In some embodiments, the Faraday shield 849 is located between the window 811 and the chuck 817. In some embodiments, the Faraday shield 849 is not maintained in a spaced-out position relative to the coil 833. For example, the Faraday shield 849 may be directly below the window 811 without a gap. The coil 833, the Faraday shield 849, and the window 811 are each configured to be substantially horizontal to each other. The Faraday shield 849 can prevent metal or other species from being deposited on the window 811 of the processing chamber 824.

[0291] The process gas may be introduced into the processing chamber through one or more main gas inlets 860 located within the upper sub-chamber 802, and / or through one or more side gas inlets 870. Similarly, although not explicitly shown, similar gas inlets may be used to supply the process gas 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 the process gas from the processing chamber 824 and to maintain the pressure within the processing chamber 824. For example, the vacuum pump may be used to evacuate the lower sub-chamber 803 during a purging operation. Valve-controlled conduits may be used to fluidly connect the vacuum pump to the processing chamber 824 to selectively control the application of the vacuum environment provided by the vacuum pump. This may be done using closed-loop controlled flow limiting devices such as throttle valves (not shown) or pendulum valves (not shown) during working plasma processing. Similarly, a vacuum pump and a valve-controlled fluid connection to the capacitively coupled plasma processing chamber may be used. The wide range of pressures regulated within the processing chamber for integrated dry developing and etching may be achieved by a variable-speed vacuum system, a throttle valve, by adjusting the flow rate of the processing gas, or by using two pressure regulation systems.

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

[0293] High-frequency power is supplied from the RF power supply 841 to the coil 833, causing an RF current to flow through the coil 833. The RF current flowing through the coil 833 generates an electromagnetic field around it. The electromagnetic field generates an induced current in the upper sub-chamber 802. The physical and chemical interactions between the various ions and radicals generated and the wafer 819 etch the features of the wafer 819 and selectively deposit layers onto the wafer 819.

[0294] When the plasma grid 850 is utilized so that both the upper sub-chamber 802 and the lower sub-chamber 803 are present, the induced current acts on the gas present in the upper sub-chamber 802 to generate an electron-ion plasma within the upper sub-chamber 802. The optional internal plasma grid 850 limits the amount of hot electrons in the lower sub-chamber 803. In some embodiments, the apparatus 800 is designed and operated so that the plasma present in the lower sub-chamber 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 larger ratio of negative ions to positive ions. Volatile etching byproducts and / or deposition byproducts may be removed from the lower sub-chamber 803 through port 822. The chuck 817 disclosed herein may be operated at high temperatures in the range of about 10°C to about 250°C. The temperature depends on the processing operation and the individual recipe.

[0296] The apparatus 800 may be connected to equipment (not shown) when installed in a cleanroom or manufacturing facility. This equipment includes piping that provides processing gas, vacuum, temperature control, and environmental particle control. These components are connected to the apparatus 800 when installed in the target manufacturing facility. Furthermore, the apparatus 800 may be connected to a transfer chamber that allows for the transfer of semiconductor wafers into and out of the apparatus 800 using robotic technology with typical automation.

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

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

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

[0300] Figure 9 shows a semiconductor processing cluster tool architecture 900, comprising a vacuum-integrated deposition module, patterning module, and processing module connected to 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 module, patterning module, and processing module are vacuum-integrated according to the requirements of the specific process. Other modules, such as those for etching, may be provided in the cluster.

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

[0302] Airlocks 942 and 946 (also known as load locks or transfer modules) are connected to the VTM938 and patterning module 940. This tool architecture allows the workpiece (such as a semiconductor substrate or wafer) to be transported under vacuum to prevent reaction before exposure. The integration of the deposition module and lithography tool is facilitated by the fact that EUVL also requires very low pressure, given the strong light absorption of incident photons by the surrounding gas (H2O, O2, etc.).

[0303] As described above, this integrated architecture is merely one possible embodiment of the tools for performing the described process. The process may also be performed by a more conventional standalone EUVL scanner and an deposition reactor integrated into a cluster architecture as a module, along with other tools such as etching and stripping, as described with reference to Figure 9, except that there is no standalone or, for example, an integrated patterning module.

[0304] Airlock 942 may be an "export" load lock, referring to the removal of a substrate from the VTM 938 supplying the deposition module 920a to the patterning module 940, and airlock 946 may be an "input" load lock, referring to the return of a substrate from the patterning module 940 to the VTM 938. The input airlock 946 may also provide an interface with the tool outside for substrate access and ejection. Each processing module has a facet connecting the module to the VTM 938. For example, the deposition processing module 920a has a facet 936. Within each facet, sensors (e.g., sensors 1-18 in the figure) are used to detect the passage of the wafer 926 as it moves between the respective stations. The patterning module 940 and the airlocks 942 and 946 may also have further facets and sensors, which are not shown.

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

[0306] It should be noted that EUVL tools typically operate under higher vacuum than deposition tools. In this case, it is preferable to increase the vacuum environment of the substrate during transport from the deposition tool to the EUVL tool to allow degassing of the substrate before it enters the patterning tool. The unloading airlock 942 provides this function by holding the wafer to be transported at a lower pressure (below the pressure inside the patterning module 940) for a certain period of time and venting all off-gases so that the optics of the patterning module 940 are not contaminated by off-gases from the substrate. A suitable pressure for the unloading 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 in the cluster structure, or it may be located outside the cluster structure, i.e., at a separate location within the manufacturing floor, and connected to the cluster structure via a network. The controller 950 may comprise one or more memory devices and one or more processors. The processor may comprise a central processing unit (CPU) or computer, analog and / or digital input / output connections, a stepper motor controller board, and other similar components. Instructions for performing appropriate control operations are executed by the processor. These instructions may be stored in memory devices associated with the controller or provided via a network. In certain embodiments, the system controller runs system control software.

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

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

[0310] It should be noted that the computer controlling wafer movement may be located locally within the cluster architecture, or it may be located outside the cluster architecture on the manufacturing floor, i.e., at a separate location, and connected to the cluster architecture via a network. A controller as described above with respect to either Figure 6, Figure 7, or Figure 8 may be implemented together with the tool in Figure 9.

[0311] Further Examples The apparatus and processes described herein may be used in conjunction with lithography patterning tools or processes for, for example, the processing or manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, such apparatus and processes are used or performed together in a common manufacturing facility, although not necessarily so. Thin film lithography patterning typically includes some or all of the following steps, each of which is performed with multiple possible tools: (1) applying a photoresist onto a workpiece (i.e., a substrate) using a spin-on or spray-on tool; (2) curing the photoresist using a hot plate or furnace or a UV curing tool; (3) exposing the photoresist to visible light or UV or X-rays using 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] knot For the sake of understanding, this embodiment has been described in some detail, but it is clear that some modifications and variations may be made within the scope of the appended claims. It should be noted that many other ways of carrying out the processes, systems, and apparatus of the present invention exist. Therefore, this embodiment is considered illustrative and not limiting, and embodiments are not limited to the details shown herein.

Claims

1. A method for performing dry development, In a processing chamber, without plasma processing, a semiconductor substrate having an EUV photosensitive photoresist film is subjected to thermal dry development using a halogen-containing gas, the EUV photosensitive photoresist film having an EUV exposure region and an EUV non-exposure region, and the thermal dry development selectively removes the EUV non-exposure region from the EUV exposure region in order to form a pattern photoresist mask. A method comprising performing plasma dry development on the semiconductor substrate by forming a plasma with at least one reaction gas to decam within the same processing chamber after the thermal dry development has been performed, wherein the plasma dry development removes residues including by-products of the thermal dry development from the EUV photosensitive photoresist film, the by-products having different compositions in the EUV exposed region and the EUV non-exposed region of the EUV photosensitive photoresist film.

2. A method according to claim 1, wherein the at least one reaction gas comprises one or more halogen-containing gases, one or more hydrogen-containing gases, or a combination thereof.

3. The method according to claim 1, wherein the at least one reaction gas comprises one or more hydrogen-containing gases, and the one or more hydrogen-containing gases are CH ４ Methods that include...

4. The method according to claim 1, wherein the at least one reaction gas comprises a plurality of halogen-containing gases, each of which is HBr, HCl, and Cl ２ , and, BCl ３ A method selected from the group consisting of the following.

5. The method according to claim 4, wherein the at least one reaction gas is HBr and Cl ２ HBr and HCl, HBr and BCl ３ , or BCl ３ A method comprising Cl2.

6. The method according to claim 1, wherein the at least one reaction gas comprises a combination of one halogen-containing gas selected from HBr, HCl, Cl ２ , and BCl ３ , and one hydrogen-containing gas selected from H ２ and CH ４ .

7. The method according to claim 6, wherein the at least one reaction gas is HBr and H ２ , BCl ３ and CH ４ , Cl ２ and CH ４ HCl and CH ４ , or HBr and CH ４ Methods that include...

8. A method according to claim 1, wherein performing plasma dry development by forming a plasma with at least one reaction gas comprises forming a plasma with at least one reaction gas and at least one non-reaction gas, wherein the non-reaction gas is N ２ A method selected from the group consisting of He, Ne, Ar, Kr, and Xe.

9. The method according to claim 8, wherein the at least one reaction gas comprises HBr, and the at least one non-reaction gas is N ２ Methods that include...

10. The method according to claim 8, wherein the at least one reaction gas is Cl ２ The at least one non-reactive gas is N ２ Methods that include...

11. A method according to claim 1, wherein the halogen-containing gas includes hydrogen halide.

12. A method according to claim 1, wherein the halogen-containing gas comprises hydrogen bromide (HBr).

13. A method according to claim 1, wherein the thermal dry development is performed at a first pressure in the processing chamber, and the plasma dry development is performed at a second pressure lower than the first pressure in the same processing chamber, and the transition from the first pressure to the second pressure in the processing chamber is performed within 10 seconds.

14. A method according to claim 1, wherein the hot dry development and the plasma dry development are performed at a temperature of about -60°C to about 120°C.

15. A method according to claim 1, wherein the thermal dry development and the plasma dry development are performed alternately in the same processing chamber.

16. A method according to claim 1, wherein the plasma dry development is cyclic plasma dry development, direct plasma dry development, remote plasma dry development, or continuous plasma dry development.

17. A method according to claim 16, wherein the plasma dry development is continuous plasma dry development, and the continuous plasma dry development is performed with variable power, constant power and pulse bias, or variable power and pulse bias.

18. An apparatus for performing dry development, Processing chamber and A controller having at least one processor and memory, Equipped with, The aforementioned controller, In a plasma-free process, a halogen-containing gas is used to perform a thermal dry development on a semiconductor substrate equipped with an EUV photosensitive photoresist film in the processing chamber, wherein the EUV photosensitive photoresist film comprises an EUV exposure region and an EUV non-exposure region, and the thermal dry development selectively removes the EUV non-exposure region from the EUV exposure region in order to form a pattern photoresist mask. An apparatus comprising a command to perform plasma dry development on the semiconductor substrate in the same processing chamber by forming a plasma of at least one reaction gas to decam after the thermal dry development has been performed, wherein the plasma dry development removes residues from the EUV photosensitive photoresist film, including by-products of the thermal dry development, the by-products having different compositions in the EUV exposed region and the non-exposed region of the EUV photosensitive photoresist film.

19. The apparatus according to claim 18, wherein the at least one reaction gas includes one or more halogen-containing gases, one or more hydrogen-containing gases, or a combination thereof.

20. The apparatus according to claim 18, wherein the at least one reaction gas comprises a plurality of halogen-containing gases, each of which is HBr, HCl, and Cl ２ , and, BCl ３ A device selected from the group consisting of the following.

21. The apparatus according to claim 18, wherein the at least one reaction gas is HBr, HCl, Cl ２ , and, BCl ３ A halogen-containing gas selected from and H ２ and CH ４ An apparatus that includes a combination with one hydrogen-containing gas selected from.

22. The apparatus according to claim 18, wherein the controller is configured to provide commands for performing plasma dry development by forming a plasma with at least one reaction gas, and is configured to provide commands for forming a plasma with at least one reaction gas and at least one non-reaction gas, wherein the non-reaction gas is N ２ An apparatus selected from the group consisting of He, Ne, Ar, Kr, and Xe.

23. The apparatus according to claim 18, wherein the halogen-containing gas includes hydrogen halide.

24. The apparatus according to claim 18, wherein the halogen-containing gas includes hydrogen bromide (HBr).

25. The apparatus according to claim 18, further, One or more pressure regulating devices, One or more pumps that are fluidly connected to the one or more pressure regulating devices, Equipped with, An apparatus in which the thermal dry developing is performed at a first pressure, and the plasma dry developing is performed at a second pressure lower than the first pressure.

26. The apparatus according to claim 18, wherein the controller, which is configured to provide commands for performing thermal dry development and plasma dry development, is configured to provide commands for performing thermal dry development and plasma dry development at temperatures from about -60°C to about 120°C.

27. The apparatus according to claim 18, wherein the controller is further configured to provide commands for alternately repeating the thermal dry development and the plasma dry development.

28. The apparatus according to claim 18, wherein the plasma dry developing is cyclic plasma dry developing, direct plasma dry developing, remote plasma dry developing, or continuous plasma dry developing.

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

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