Plasma activating solution

Abstract

Plasma-activated liquids and methods of using same are described. In one aspect, a method for fabricating integrated circuits includes activating a photolithographic liquid with a plasma; and treating a device component with the activated photolithographic liquid. In one example, the photolithographic liquid is a photoresist. Activating the photoresist liquid can introduce reactive species into the photoresist.

Description

Detailed Description of the Invention

[0001] [Cross - Reference to Related Applications]

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 111,577, filed on November 9, 2020, which is hereby incorporated by reference in its entirety.

[0002] [Background of the Invention]

[0002] The manufacture of integrated circuits requires the use of specialized chemicals in several important steps. An important processing step involves the exposure of photoresist to electromagnetic radiation, which causes chemical changes in the photoresist such that, by subsequent steps and the chemical application of a developer, only the material exposed to light or only the material not exposed to light can be removed. This creates a pattern in the underlying layer, which can then be etched. After etching, in many cases, another step called ashing, which uses plasma, removes the residual photoresist material without damaging the underlying layer. One problem with conventional chip manufacturing is that the chip still contains residues after the ashing step. Therefore, another chemical step is required after the ashing step. Cleaning solutions are often used to remove such residues.

[0003]

[0003] Recently, integrated circuit manufacturing lithography has undergone dramatic technological changes. The latest and smallest chips now use extreme ultraviolet (EUV) as the light source for lithography. EUV lithography utilizes an electromagnetic radiation wavelength of approximately 13.5 nm (about 100 eV photons) instead of the more conventional wavelength of 193 nm (about 5 eV photons). One limitation of current technology is that the sensitivity of conventional photoresists is not sufficient. In conventional photoresists, the current level of energy required to expose a pattern is approximately 40 mJ / cm 2However, in order to minimize the line edge roughness of features caused by photolithography while simultaneously achieving the desired processing capacity in mass manufacturing, the industry has been using 10-15 mJ / cm³ of photoresist. 2 The goal is to develop photoresists that can be exposed using the intensity of electromagnetic radiation that provides the desired effect.

[0004]

[0004] Consequently, while the industry has rapidly adopted EUV in the exposure step, the technologies for other steps, including photoresist chemistry, as well as the technologies for developers and cleaning solutions, have not yet caught up with the major shift in EUV. The chemicals involved are still substantially the same as those used for many years in conventional 193nm lithography, and these chemicals do not function similarly when needed. Therefore, it can be recognized that improved photoresists, developers, and cleaning solutions are needed.

[0005] [Overview of the prefecture]

[0005] In one aspect of the present invention, a chemical substance, such as a photolithography chemical, is "activated" using plasma before use. Plasma activation can generate several long-lived chemical species in the liquid, for example, (1) free radicals, (2) solvated electrons, and / or (3) metastable compounds that are difficult to synthesize by other means, although this is not constrained by theory.

[0006]

[0006] In some embodiments, the method uses atmospheric pressure plasma to act on the chemicals or components of the final chemical mixture to activate it. This chemical mixture can then exhibit enhanced effectiveness compared to the same mixture that has not been treated with plasma.

[0007]

[0007] In some embodiments, the plasma activating solution comprises a non-aqueous liquid medium and at least one reactive chemical species generated by bringing the surface of the non-aqueous liquid medium into contact with the plasma. In some embodiments, the at least one reactive chemical species comprises a free radical, a solvated electron, or both.

[0008]

[0008] In one embodiment, the plasma activating solution contains 5% by weight or less of water. In one embodiment, the plasma activating solution contains 3% by weight or less of water. In one embodiment, the plasma activating solution contains 2% by weight or less of water. In one embodiment, the plasma activating solution contains 1% by weight or less of water. In one embodiment, the plasma activating solution contains 0.1% by weight or less of water. In one embodiment, the plasma activating solution contains 0.01% by weight or less of water. In one embodiment, the plasma activating solution contains 0.001% by weight or less of water.

[0009]

[0009] In some embodiments, the plasma activator contains free radicals, solvated electrons, or both. In some embodiments, the plasma activator contains a photolithography solution. In some embodiments, the photolithography solution is a photoresist solution. In some embodiments, the photolithography solution is a developing solution. In some embodiments, the photolithography solution is a cleaning solution.

[0010]

[0010] In some embodiments, the plasma activating solution comprises a plurality of molecules, each of which comprises a carbon backbone. In some embodiments, each of the plurality of molecules comprises at least one covalent bond that directly or indirectly attaches an acid group to the carbon backbone.

[0011]

[0011] In some embodiments, the plasma activator contains ionic chemical species that stabilize free radicals and / or solvated electrons, or more.

[0012]

[0012] In one embodiment, a method for manufacturing an integrated circuit includes the steps of activating a photolithography solution with plasma; and processing device components with the activated photolithography solution. In some embodiments, the activation step includes bringing the photolithography solution into contact with plasma.

[0013]

[0013] In some embodiments, the activation step includes generating free radicals, solvated electrons, or both in the photolithography solution. In some embodiments, the activation step includes weakening at least one covalent bond in one or more molecules of the photolithography solution.

[0014]

[0014] In some embodiments, the activation step includes weakening at least one covalent bond in each of a plurality of solvation molecules of the photolithography solution, wherein each of the plurality of molecules includes a carbon backbone. In some embodiments, the at least one covalent bond directly or indirectly attaches an acid group to the carbon backbone. In some embodiments, the activation step includes stabilizing the free radical and / or solvation electrons with a cation.

[0015]

[0015] In some embodiments, the activation step includes stabilizing the free radical and / or solvation electrons with one or more functional groups supported by the carbon backbone. In some embodiments, one or more functional groups include cationic functional groups. In some embodiments, one or more functional groups include anionic functional groups.

[0016]

[0016] In some embodiments, the photolithography solution is selected from the group consisting of a photoresist solution, a developer solution, and a washing solution. In some embodiments, the activation step is performed before the processing step. In some embodiments, the processing step includes bringing a device component into contact with the activated photolithography solution. In some embodiments, the device component includes a semiconductor wafer.

[0017]

[0017] In one embodiment, the photolithography solution may include a photoresist solution. In some embodiments, the photolithography solution includes a positive-type photoresist. In some embodiments, the photolithography solution includes a negative-type photoresist.

[0018]

[0018] In some embodiments, the method includes the step of curing a photoresist solution onto a solid layer of photoresist on a semiconductor wafer, wherein, after the curing step, free radicals and / or solvated electrons generated by the contact step are captured by the solid layer of photoresist.

[0019]

[0019] In some embodiments, the method includes the steps of exposing a solid layer of photoresist to a pattern of electromagnetic radiation, and in response to the exposure step, releasing at least a portion of the electrons and / or solvated electrons of the captured free radicals, thereby breaking covalent or ionic bonds in the solid layer of photoresist.

[0020]

[0020] In some embodiments, the method includes a step of releasing acid groups in the solid layer of the photoresist in response to the emission step. In some embodiments, the electromagnetic radiation includes extreme ultraviolet radiation. In some embodiments, the electromagnetic radiation exhibits an intensity peak in the wavelength range of 13.3 to 13.7 nm.

[0021]

[0021] In one embodiment, the plasma may be an atmospheric pressure plasma. In some embodiments, the contact step is performed in a controlled gas environment under reduced pressure. In some embodiments, the plasma is formed by a direct current. In some embodiments, the plasma is a surface wave plasma. In some embodiments, the plasma is formed using an RF source or a microwave source. In one embodiment, a method for manufacturing an integrated circuit includes the steps of coating at least a portion of a surface device component with a photoresist solution, curing the photoresist solution into a solid layer of photoresist on a wafer, exposing the solid layer of photoresist to a pattern of electromagnetic radiation, contacting the photoresist with a developing liquid to develop the corresponding pattern in the photoresist, etching the wafer to transfer the pattern from the photoresist to a layer below the photoresist layer, ashing the residual photoresist, and washing the wafer with a cleaning solution to remove photoresist residue from the wafer. Furthermore, at least one of the following steps may be performed: activating the photoresist solution or components of the photoresist solution with plasma; activating the developer solution or components of the developer solution with plasma; and / or activating the cleaning solution solution or components of the cleaning solution with plasma.

[0022]

[0022] In some embodiments, the method may include a step of activating the photoresist solution with plasma before or simultaneously with the coating step. In some embodiments, the method may include a step of activating the developer solution with plasma before or simultaneously with the contact step. In some embodiments, the method may include a step of activating the cleaning solution with plasma before or simultaneously with the cleaning step.

[0023]

[0023] In one aspect of the present invention, a method for manufacturing an integrated circuit may include the steps of: coating at least a portion of a surface device component with a photoresist solution; curing the photoresist solution into a solid layer on a wafer; exposing the photoresist to electromagnetic radiation; removing the exposed photoresist by applying a developing solution; activating the developing solution with plasma before or simultaneously with the application step to introduce free radicals and / or solvated electrons into the developing solution; etching the exposed portion of the wafer; ashing the residual photoresist; and removing the photoresist residue with a liquid cleaning solution.

[0024]

[0024] In one aspect of the present invention, a method for manufacturing an integrated circuit includes the steps of: coating at least a portion of a surface device component with a photoresist solution; curing the photoresist solution into a solid layer on a wafer; exposing the photoresist to electromagnetic radiation; removing the exposed photoresist by applying a developing liquid; etching the exposed portion of the wafer; ashing the residual photoresist; removing the photoresist residue with a liquid cleaning solution; and, before or simultaneously with the removal step, activating the liquid cleaning solution with plasma to introduce free radicals and / or solvated electrons into the liquid cleaning solution.

[0025]

[0025] In some embodiments, instead of ashing the device components, residual photoresist can be removed by stripping liquid. The stripping liquid may optionally be plasma-activated by the plasma liquid activation method described herein.

[0026]

[0026] In some embodiments, the method includes, for example, mixing a first component and a second component to form a liquid cleaning solution prior to the removal step. In some embodiments, the activation step includes, for example, activating the first component with plasma prior to the mixing step. In some embodiments, the method includes applying plasma to one of the components of the photolithography chemicals and then mixing that component with the other components to produce the chemical.

[0027]

[0027] In one embodiment, a method of manufacturing an integrated circuit includes coating at least a portion of a surface device component with a photoresist solution, curing the photoresist solution into a solid layer on a wafer, exposing the photoresist to electromagnetic radiation, applying a developing liquid to remove the exposed photoresist, etching the exposed portion of the wafer, ashing the remaining photoresist, and removing the photoresist residue with a liquid cleaning solution. Prior to or simultaneously with the coating step, the photoresist solution or a component of the photoresist solution may be activated by plasma, thereby introducing free radicals and / or solvated electrons into the photoresist solution or a component of the photoresist solution.

[0028]

[0028] In one embodiment, a method of manufacturing an integrated circuit includes coating at least a portion of a surface device component with a photoresist solution, curing the photoresist solution into a solid layer on a wafer, exposing the photoresist to electromagnetic radiation, applying a developing liquid to remove the exposed photoresist, etching the exposed portion of the wafer, ashing the remaining photoresist, and removing the photoresist residue with a liquid cleaning solution. Prior to or simultaneously with the application step, the developing liquid or a component of the developing liquid may be activated by plasma, thereby introducing free radicals and / or solvated electrons into the developing liquid or a component of the developing liquid.

[0029]

[0029] In one embodiment, a method of manufacturing an integrated circuit includes coating at least a portion of a surface device component with a photoresist solution, curing the photoresist solution into a solid layer on a wafer, exposing the photoresist to electromagnetic radiation, applying a developing liquid to remove the exposed photoresist, etching an exposed portion of the wafer, ashing the remaining photoresist, and removing the photoresist residue with a liquid cleaning solution. Before or simultaneously with the removing step, the liquid cleaning solution or a component of the liquid cleaning solution may be activated by plasma, thereby introducing free radicals and / or solvated electrons into the liquid cleaning solution or the component of the liquid cleaning solution.

[0030]

[0030] While not desiring to be bound by any particular theory, there may be a discussion herein of the underlying principles associated with the devices and methods disclosed herein. Without regard to the ultimate accuracy of any mechanistic explanations or hypotheses, it is recognized that embodiments of the present invention may still be effective and useful.

Brief Description of the Drawings

[0031] [Figure 1] FIG. 1 is a schematic diagram of a plasma activation device useful in the manufacture of some embodiments of the present invention. [Figure 2] FIG. 2 is a flowchart illustrating a method of manufacturing an integrated circuit and showing where a plasma activation step may be introduced. [Figure 3] FIG. 3 is an illustration of some intermediate steps of the method of FIG. 2. [Figure 4A] FIGS. 4A - B are charts of current and voltage versus time (tie) for an AC remote plasma jet used to pre - treat a photoresist solution according to an embodiment of the present invention. FIG. 4A shows the plasma jet in a "low" output mode having an average current of 1.2 mA. FIG. 4B shows the plasma jet in a "high" output mode having an average current of 1.5 mA. [Figure 4B] Figures 4A and 4B are current and voltage-to-time (tie) charts of an AC remote plasma jet used for pre-treating a photoresist solution according to one embodiment of the present invention. Figure 4A shows the plasma jet in "low" power mode with an average current of 1.2 mA. Figure 4B shows the plasma jet in "high" power mode with an average current of 1.5 mA. [Figure 4C] Figures 4C to 4D are photographs of the plasma jet shown in Figures 4A and 4B, respectively. [Figure 4D] Figures 4C to 4D are photographs of the plasma jet shown in Figures 4A and 4B, respectively. [Figure 5] Both images show a parallel comparison of plasma-activated photoresists after exposure and development (right), compared to a control photoresist (left) that was exposed to light for 5 seconds and developed under the same conditions. [Figure 6A] Both images show a second parallel comparison of plasma-activated photoresists after exposure and development (right), compared to a control photoresist (left) that was exposed for 3 seconds and developed under the same conditions. [Figure 6B] This is a photograph of the second target photoresist (without plasma treatment) after gas flow was applied to eliminate the effects of potential evaporation. [Figure 7A] Both images show a parallel comparison of plasma-activated photoresist after exposure and development (right), compared to a control photoresist (left) that was exposed for 4 seconds and developed under the same conditions. [Figure 7B] Both images show parallel comparisons of plasma-activated photoresists after exposure and development (right), compared to a control photoresist (left) that was exposed for 5 seconds and developed under the same conditions. [Figure 8] This is a schematic diagram of one embodiment of a pulsed plasma apparatus useful for plasma processing, according to some embodiments of the present disclosure. [Figure 9A]This is a schematic diagram of a second embodiment of a pulsed plasma apparatus useful for plasma processing, according to some embodiments of the present disclosure. [Figure 9B] Figure 9A is a graph showing the output of the pulsed plasma device. [Figure 10] Figures 6-8 are schematic diagrams illustrating the method for manufacturing an integrated circuit according to the embodiments shown.

[0032] [Description of chemical compounds and their nomenclature]

[0045] In general, the terms and expressions used herein have meanings recognized in the art, which can be found by referring to standard textbooks, reference papers, and contexts known to those skilled in the art. To clarify their specific use in the context of the present invention, the following definitions are provided.

[0033]

[0046] As used herein, “plasma activated solution” is a liquid (e.g., solvent, solution, mixture, suspension, slurry, emulsion) that has been modified by plasma to have improved reactivity compared to the same initial liquid sample that has not been treated with plasma. In this regard, plasma activation of a liquid can introduce reactive chemical species into the liquid, such as free radicals, solvated electrons, or other stable / metastable reactive chemical species. A plasma activated solution may include a mixture of a plasma activated solution and a non-activated liquid.

[0034]

[0047] As used herein, "non-aqueous liquid medium" refers to a liquid medium in which water is less than half by weight. In some embodiments, the non-aqueous liquid medium may contain 5% by weight or less of water. In some embodiments, the non-aqueous liquid medium may contain 3% by weight or less of water. In some embodiments, the non-aqueous liquid medium may contain 2% by weight or less of water. In some embodiments, the non-aqueous liquid medium may contain 1% by weight or less of water. In some embodiments, the non-aqueous liquid medium may contain 0.1% by weight or less of water. In some embodiments, the non-aqueous liquid medium may contain 0.01% by weight or less of water. In some embodiments, the non-aqueous liquid medium may contain 0.001% by weight or less of water.

[0035]

[0048] As used herein, “reactive species” means multiple identical atoms, molecules, ions, or radicals that have a tendency to react chemically.

[0036]

[0049] As used herein, “photolithography solution” refers to a liquid used to create an integrated circuit. Photolithography solutions include liquids used to prepare device components (e.g., semiconductor wafers) for the photolithography process; liquids used in the photolithography process; and liquids used to remove residues and clean the device components after the photolithography process. Examples of photolithography solutions include photoresist solutions, developer solutions, and cleaning solutions.

[0037]

[0050] As used herein, "photoresist liquid" refers to a liquid containing a photosensitive material, such as a liquid resin, used in photolithography to form a photosensitive photoresist layer on the surface of a device component. The photoresist layer can then be patterned by exposing it to a pattern of electromagnetic radiation, for example, using a photomask. In some embodiments, the photoresist liquid is configured to harden into a solid layer on the surface. In some embodiments, the photoresist liquid is configured to form a positive-type photoresist layer. In some embodiments, the photoresist liquid is configured to form a negative-type photoresist layer.

[0038]

[0051] As used herein, "developing liquid" refers to a liquid configured to remove a portion of the photoresist layer in order to pattern the photoresist. Generally, developing liquid is used after the photoresist has been exposed to a pattern of electromagnetic radiation. In the case of positive-type photoresists, the developing liquid can remove a portion of the photoresist that has been exposed to electromagnetic radiation. In the case of negative-type photoresists, the developing liquid can remove a portion of the photoresist that has not been exposed to electromagnetic radiation.

[0039]

[0052] As used herein, “cleaning solution liquid” refers to a liquid configured, for example, to remove residue from a device component after ashing a photoresist. Cleaning solution liquid is sometimes also referred to as “thinner liquid.”

[0040]

[0053] As used herein, "stripper liquid" refers to a liquid configured to remove residual photoresist after etching a pattern onto the surface of a device component.

[0041]

[0054] As used herein, "extreme ultraviolet radiation" refers to electromagnetic radiation having wavelengths between 124 nm and 2 nm. In some embodiments, the extreme ultraviolet radiation has an intensity peak in the wavelength range of 13.3 to 13.7 nm. In some embodiments, the extreme ultraviolet radiation has an intensity peak at approximately 13.5 nm.

[0042]

[0055] As used herein, "controlled gas environment" means a closed environment in which at least one of the pressure, temperature, and / or gas composition is controlled.

[0043]

[0056] As used herein, “device component” means a component of an electrical circuit or a small component thereof. Examples of device components include capacitors, diodes, resistors, integrated circuits, or their components, including semiconductor wafers which may include oxide layers and / or metal layers.

[0044] [Detailed description of the invention]

[0057] In the following description, numerous specific details of the devices, device components, and methods of the present invention are described in order to provide a complete description of the precise nature of the invention. However, it will be apparent to those skilled in the art that the invention can be carried out without these specific details.

[0045]

[0058] Figure 1 is a schematic diagram of a plasma activation apparatus 10 useful for manufacturing some embodiments of the present invention. The apparatus 10 includes a controlled gas environment 100, a cathode 200, an anode 250, and a plasma 150. The plasma 150 may be in contact with the surface of a non-aqueous liquid 300. As a result of contact with the plasma 150, the plasma can activate the liquid 300. For example, the plasma 150 can introduce free radicals, solvated electrons, and / or other metastable reactive chemical species into the liquid 300. Although we do not wish to be bound by theory, it is thought that electrons exist in the liquid as free electrons for a short time, altering chemical bonds, and then such changes in chemical bonds are stabilized by the dipoles of polar molecules and / or ions in the liquid 300.

[0046]

[0059] In the exemplary embodiments, the plasma 150 may be a DC plasma generated by an anode 250 and a cathode 200. The control gas environment 100 may be controlled to atmospheric pressure or a pressure near atmospheric pressure. The distance between the plasma and the liquid may be approximately 1 mm. In some embodiments, the plasma may be a plasma generated by dielectric barrier discharge. In some embodiments, the plasma may be a radio frequency (rf) plasma.

[0047]

[0060] In the illustrated embodiments, the anode 250 is immersed in or partially immersed in the liquid 300. In alternative embodiments, the anode may be the liquid itself or a conductive plate beneath the liquid. In further alternative embodiments, the apparatus may comprise a plurality of plasma jets striking the liquid. The plurality of plasma jets may comprise one or more capillary and / or one or more slot-shaped electrodes. In some embodiments, the gas in the control gas environment includes an inert gas. In some embodiments, the control gas environment may be configured to deliver one or more gaseous chemical compounds by a bubbler, atomizer or evaporator. In some embodiments, the plasma may be a surface wave plasma.

[0048]

[0061] In some embodiments, in addition to or as a substitute for electrodes, the apparatus may include nozzles positioned below the surface of the liquid to introduce gas into the liquid. When an Al current flows through the nozzles and is introduced into the liquid, it can generate plasma in the gas. Example DBD plasma conditions [Table 1]

[0049]

[0062] In some embodiments, the control gas environment may be controlled to a pressure higher than atmospheric pressure. In some embodiments, the control gas environment may be controlled to a pressure lower than atmospheric pressure.

[0050]

[0063] Figure 2 is a flowchart illustrating a method for manufacturing an integrated circuit. Figure 3 is an example of some intermediate products of the method in Figure 2. In the method 20 illustrated in the examples of Figures 2-3, liquid component A 502 is mixed with components B 504 and C 506 to form a photoresist solution 508. In other examples, any number of components may be mixed to form a photoresist solution. Component A is plasma-activated in step 400A before mixing. Thus, one or more reactive chemical species may be added to component A. Optionally, components B and / or C may be similarly plasma-activated by optional steps 400B and 400C. In other examples, the photoresist solution may be mixed before the plasma activation step(s).

[0051]

[0064] Next, a device component 600, such as a wafer, is prepared. Optionally, the wafer may have at least one layer 610. The layer(s) 610 has at least one surface. In one embodiment, at least one surface is the surface of the oxide layer of the wafer. In one embodiment, at least one surface is the surface of the metal layer of the wafer. In one embodiment, at least one surface is the surface of the silicon layer of the wafer. In step 530, the layer 610 is spin-coated with liquid photoresist to form a photoresist coating 508. The photoresist coating 508 can then be cured into a solid layer of photoresist, for example, by drying at a high temperature. The photoresist layer can cover at least one surface of the wafer. At least some of the reactive chemical species, for example, free radicals and / or solvated electrons originating from the plasma activation step 400A (and optionally 400B and 400C), are captured in the coating 508 and can maintain their reactive form for a period of time.

[0052]

[0065] Next, the coated device component is exposed to a pattern of electromagnetic radiation by a photomask, for example, in step 540. In one embodiment, the electromagnetic radiation is EUV radiation. In another embodiment, the electromagnetic radiation is UV radiation. In one aspect, reactive chemical species captured in coating 508 can result in enhanced photoreactivity to the photoresist. Therefore, in some embodiments, a plasma-activated photoresist may allow the use of electromagnetic radiation with an even lower total energy per unit area during the exposure step. In this regard, the line edge roughness of the resulting feature 710 in layer 610 may be improved.

[0053]

[0066] In parallel, a developer solution can be prepared by mixing component A520 with components B522 and C524. In other examples, any number of components can be mixed to form a developer solution 526. Optionally, components A, B and / or C520, 522, and 524 may be plasma-activated by optional steps 400H, 400I, and 400J, thereby introducing reactive chemical species into the developer solution 526.

[0054]

[0067] Next, the exposed device component is developed 550 with developer liquid 526 to remove the exposed photoresist and generate features in the photoresist layer using a photomask. In such embodiments where the developer liquid 526 is plasma-activated, reactive chemical species in the developer liquid 526 may enhance the effectiveness of the developer liquid.

[0055]

[0068] Next, the patterned wafer can be etched in step 560 to transfer the photomask pattern from coating 508 to layer 610. In parallel, a cleaning solution (or thinner) 516 can be prepared by mixing component A 510 with components B 512 and C 514. In other examples, any number of components can be mixed to form the cleaning solution liquid 516. Optionally, components A, B and / or C 510, 512, and 514 may be plasma-activated by optional steps 400D, 400E, and 400F, thereby introducing reactive chemical species into the cleaning solution liquid 516.

[0056]

[0069] After etching step 560, in some embodiments, residual photoresist may be removed by plasma ashing. In other embodiments, residual photoresist may be removed by chemical stripping with a stripper solution. The stripper solution and / or its components may be plasma-activated by the methods disclosed herein, thereby introducing reactive chemical species into the stripper solution. Plasma-activated stripper solution may exhibit enhanced effectiveness.

[0057]

[0070] Next, the cleaning solution liquid 516 can be applied to the device component 600 to remove photoresist residue. In such embodiments, where the cleaning solution liquid 516 is plasma-activated, the reactive chemical species in the cleaning solution liquid 516 can enhance the effectiveness of the cleaning solution liquid.

[0058]

[0071] Next, in step 580, the patterned and cleaned device component 700 may be prepared for the next processing step.

[0059]

[0072] The present invention can be further understood by the following non-limiting examples.

[0060]

[0073] Example 1: Plasma-activated photoresist solution

[0074] A conventional positive-type photoresist is prepared. This photoresist contains four components: a matrix or base material (resin), a sensitizer which is a photoactive compound (PAC) that also contains acid-generating groups, a quencher which can capture excess acid, and a solvent which adjusts viscosity. The photoresist is a chemically activated resist (CAR). A photon collides with a specific bond in the material, releasing acid. This acid then converts to release even more acid groups. Once the acid takes effect, it breaks down the polymer and monomer chains, and as a result, the developer can wash them away. The quencher removes the acid groups and maintains balance.

[0061]

[0075] The photoresist is plasma-activated using the apparatus shown in Figure 1, applied to a wafer, and exposed to EUV light. The exposed wafer is developed, etched, and cleaned. The line edge roughness of the resulting features is reduced.

[0062]

[0076] While we do not wish to be bound by theory, solvated electrons can bind to compounds in the resist, thereby altering the chemical bonds, possibly the strength or presence of polymer chains, and / or, if not, being stabilized by ions in the liquid. The polymer chains, then, may become more easily broken by the addition of energy than in the absence of the solvated electron effect. EUV photons incident on a plasma-activated photoresist generate photoelectrons, which can in turn generate secondary electrons, but will require very few electrons to break weaker bonds. Thus, the required dose of EUV can be reduced, and line edge roughness is improved because little chemical amplification is needed.

[0063]

[0077] Example 2: Plasma-activated cleaning solution liquid

[0078] Prepare a conventional cleaning solution liquid.

[0064]

[0079] The cleaning solution is plasma-activated using the apparatus shown in Figure 1. A wafer is coated with photoresist and exposed to EUV light. The exposed wafer is developed and etched. The etched wafer is then cleaned with the plasma-activated cleaning solution. This increases the effectiveness of the cleaning solution.

[0065]

[0080] Example 3: Plasma-activated developing liquid

[0081] Prepare a developer solution containing TMAH (tetramethiammonium hydroxide) and a buffer solution to control the pH. This developer solution is plasma-activated using the apparatus shown in Figure 1. A wafer is coated with photoresist and exposed to EUV light. Next, the exposed wafer is developed with the plasma-activated developer solution. This increases the effectiveness of the developer solution, resulting in a clearer pattern with less line edge roughness.

[0066]

[0082] Example 4: Plasma-activated photoresist solution

[0083] Moving on to Figure 10, the polymer precursor solution was plasma-activated by treatment with a plasma jet. Next, the plasma-activated precursor solution was combined with a solvent, photoactive groups (PAGs), and a quencher to produce a plasma-activated photoresist. The plasma-activated photoresist was applied to a substrate, baked, exposed to UV light, and developed. In a direct comparison with a control experiment that replicated all conditions except the plasma treatment, the plasma-activated photoresist showed improved sensitivity to UV exposure. The amount of energy required per unit area to generate a clear pattern decreased.

[0067]

[0084] All processing was performed using an AC remote plasma jet. Two different power settings of the plasma device, namely "low" and "high" power, were used. The two levels of power output are shown in Figure 4. The "low" power is 10% of the power supply, with an average current of 1.2 mA. The "high" power is 15% of the power supply, with an average current of 1.5 mA. After processing the samples, they were exposed to light within 2-3 hours.

[0068]

[0085] A photoresist polymer precursor liquid containing organic disulfides and additional functional groups based on acrylates with polymerizable and acid-forming alkyl esters was used. This was dissolved in a solvent containing glycol ether.

[0069]

[0086] Figure 5 demonstrates the beneficial effects of plasma activation of the photoresist solution. Specifically, the sample on the right was prepared by plasma-treating the polymer precursor solution at "high" power for 60 minutes, then mixing this plasma-activated polymer precursor solution with the photoresist, coating the substrate, exposing it for 5 seconds, and then developing it. The control sample on the left was prepared in the same manner, except that the plasma treatment step was omitted. Lithography of the plasma-activated sample clearly shows sharper edges and enhanced development compared to the control, as can be seen from the parallel photographs.

[0070]

[0087] Figure 6A shows another parallel comparison, this time with a shorter exposure time. The sample on the right was prepared by plasma-treating the polymer precursor solution for 60 minutes, then mixing the plasma-activated polymer precursor solution with photoresist, coating the substrate, exposing it to UV light for 3 seconds, and then developing it. The control sample on the left was prepared in the same manner, except that the plasma treatment step was omitted. As can be seen, the lithography of the plasma-activated sample shows sharp edges and complete development, while the control is hardly developed at all.

[0071]

[0088] Figure 6B shows a second control to the experiment in Figure 6A. Specifically, the sample in Figure 6B was prepared in the same way as the plasma-activated sample shown in Figure 6A, except that the sample was subjected to a gas flow for 60 minutes instead of the plasma activation step, in order to eliminate any effects of evaporation associated with the plasma jet. As can be seen in Figure 6B, the gas flow did not improve the lithography, which suggests that the plasma itself produced the results in Figure 6A.

[0072]

[0089] Figure 7A shows the results of a parallel comparison identical to the experiment shown in Figure 6A, except that the exposure time was 4 seconds. Figure 7B shows the results of a parallel comparison identical to the experiment shown in Figure 6A, except that the exposure time was 5 seconds.

[0073]

[0090] Thus, in some embodiments, plasma activation of the photoresist solution can enable even shorter development times, thereby improving the processing capacity of commercial integrated circuit manufacturing. In other embodiments, plasma activation of the photoresist solution can enable lower radiation output for development, thereby improving the line edge roughness of very small devices.

[0074]

[0091] Description of incorporated and modified forms by reference

[0092] All references in this application, including patent documents, such as granted or awarded patents or equivalents; patent application publications; and non-patent literature documents or other materials, are incorporated herein by reference in whole, as if each reference were incorporated individually by reference to the extent that it does not contradict, at least partially, the disclosures in this application (for example, partially contradictory references are incorporated by reference, except for the partially contradictory portion of the reference).

[0075]

[0093] The terms and expressions used herein are for illustrative purposes only and not for limiting purposes, and are not intended to exclude any equivalents or parts thereof of the features shown and described, however it is recognized that various modifications are possible within the scope of the claimed invention. Therefore, while the invention is specifically disclosed by preferred embodiments, exemplary embodiments and optional features, it should be understood that modifications and variations of the concepts disclosed herein can be made by those skilled in the art, and that such modifications and variations are considered to fall within the scope of the invention as defined by the appended claims. The specific embodiments provided herein are examples of useful embodiments of the invention, and it will be apparent to those skilled in the art that the invention can be carried out using numerous variations of the devices, device components, and method steps described herein. As will be apparent to those skilled in the art, useful methods and devices for the present invention may include numerous optional compositions and processing elements and steps.

[0076]

[0094] In use herein and in the appended claims, the singular forms “a,” “an,” and “the” include multiple references unless the context specifically indicates otherwise. For example, “cell” includes multiple such cells and their equivalents known to those skilled in the art. Similarly, the terms “a” (or “an”), “one or more,” and “at least one” are interchangeable herein. It should also be noted that the terms “comprising,” “including,” and “having” are interchangeable. The expression “as described in any one of claims XX to YY” (wherein XX and YY refer to claim numbers) is intended to present multiple independent claims in alternative forms and, in some embodiments, is interchangeable with the expression “to any one of claims XX to YY.”

[0077]

[0095] Where a group of substituents is disclosed herein, it is understood that all individual members of that group, including any isomers, enantiomers, and diastereomers of the group members, and all subgroups are disclosed separately. Where a Markush group or other classification is used herein, it is intended that all individual members of that group, and all possible combinations and subcombinations of that group, are included separately in this disclosure. For example, where a compound is described herein in such a way that no specific isomer, enantiomer, or diastereomer of the compound is specified in its formula or chemical name, the description is intended to include each isomer and enantiomer of the compound described separately, or any combination thereof. Furthermore, unless otherwise specified, all isotopic variants of the compounds disclosed herein are intended to be encompassed by this disclosure. For example, it will be understood that one or more hydrogen atoms in any of the disclosed molecules may be replaced with deuterium or tritium. Isotopic variants of molecules are generally useful as standards in assays relating to molecules, and in chemical and biological studies relating to molecules or their use. Methods for preparing such isotopic variants are well known in the art. The specific names of the compounds are intended to be illustrative, as it is known that the same compound may be called by different names by those skilled in the art.

[0078]

[0096] Certain molecules disclosed herein may contain one or more ionizable groups [groups from which protons can be removed (e.g., -COOH), or groups from which protons can be added (e.g., amines), or groups from which quaternization can be performed (e.g., amines)]. All possible ionic forms of such molecules and their salts are intended to be individually included herein. With respect to salts of compounds herein, those skilled in the art can select from a wide range of available counterion salts suitable for the preparation of the salt of the present invention for a given application. For a particular application, a given selection of anion or cation for the preparation of the salt may result in an increase or decrease in the solubility of the salt.

[0079]

[0097] Any device, system, formulation, combination of components, or method described or illustrated herein may be used to carry out the present invention unless otherwise specified.

[0080]

[0098] Wherever a range, such as a temperature range, a time range, or a range of composition or concentration, is given herein, it is intended that all intermediate and partial ranges, as well as all individual values ​​within a given range, are included in this disclosure. Any partial range, or individual values ​​within a range or partial range, included herein may be excluded from the claims herein.

[0081]

[0099] All patents and publications specified herein represent the level of skill of those skilled in the art to which the present invention relates. References cited herein are incorporated herein in their entirety by reference to indicate the most current art as of the date of publication or filing, and it is intended that this information may be used herein to exclude, where necessary, certain embodiments present in the prior art. For example, if a composition of a substance is claimed, it should be understood that compounds that were publicly known and available in the art prior to the applicant's invention, including compounds for which a feasible disclosure is provided in the references cited herein, are not intended to be included in the composition of the claims of the substance herein.

[0082]

[0100] As used herein, “comprising” is synonymous with “including,” “containing,” or “characterized by,” and is comprehensive or open-ended and does not exclude additional unlisted elements or method steps. As used herein, “consisting of” excludes any element, step, or component not specified in the claim elements. As used herein, “consisting essentially of” does not exclude a substance or step that does not substantially affect the basic and novel features of the claim. In each case herein, any of the terms “including,” “consisting essentially of,” and “consisting of” may be replaced with any of the other two terms. The inventions described exemplary herein can be preferably carried out in the absence of any element(s) or limitation(s) not specifically disclosed herein.

[0083]

[0101] Those skilled in the art will understand that starting materials, biomolecules, reagents, synthesis methods, purification methods, analytical methods, assay methods, and biological methods other than those specifically exemplified may be used in the practice of the present invention without relying on excessive experimentation. All functional equivalents of any such substances and methods known in the art are intended to be included in the present invention. The terms and expressions used are for illustrative purposes only and not for limitation, and are not intended to exclude any equivalent or part thereof of the features shown and described, although it should be recognized that various modifications are possible within the scope of the claimed invention. Therefore, while the present invention is specifically disclosed by preferred embodiments and optional features, it should be understood that modifications and variations of the concepts disclosed herein can be made by those skilled in the art, and that such modifications and variations are considered to fall within the scope of the present invention as defined by the appended claims. [Item 1] Non-aqueous liquid media; and At least one reactive chemical species generated by bringing the surface of a non-aqueous liquid medium into contact with plasma. A plasma activating solution containing [the specified ingredient]. [Item 2] The plasma activator described in item 1, wherein at least one reactive chemical species comprises a free radical, a solvated electron, or both. [Item 3] A plasma activating solution as described in item 1, containing 5% by weight or less of water. [Item 4] A plasma activating solution as described in item 1, containing 3% by weight or less of water. [Item 5] A plasma activating solution as described in item 1, containing 2% by weight or less of water. [Item 6] A plasma activating solution as described in item 1, containing 1% by weight or less of water. [Item 7] A plasma activating solution as described in item 1, containing 0.1% by weight or less of water. [Item 8] A plasma activating solution as described in item 1, containing 0.01% by weight or less of water. [Item 9] A plasma activating solution as described in item 1, containing 0.001% by weight or less of water. [Item 10] A plasma activator according to any one of items 1 to 9, comprising free radicals, solvated electrons, or both. [Item 11] A plasma activating solution, including photolithography solution, as described in any one of items 1 to 10. [Item 12] A plasma activating solution as described in item 11, wherein the photolithography solution is a photoresist solution. [Item 13] The plasma activator described in item 11, wherein the photolithography solution is the developing solution. [Item 13] The plasma activating solution described in item 11, wherein the photolithography solution is a cleaning solution liquid. [Item 14] A plasma activating solution according to any one of items 1 to 13, comprising multiple solvating molecules, each of which contains a carbon main chain. [Item 15] The plasma activator according to item 14, wherein each of the multiple molecules contains at least one covalent bond that directly or indirectly attaches an acid group to a carbon backbone. [Item 16] A plasma activator according to any one of items 1 to 15, comprising ionic chemical species that stabilize free radicals and / or solvated electrons. [Item 17] A method for manufacturing an integrated circuit, A step of activating the photolithography solution with plasma; and Steps to process device components using activated photolithography solution. Methods that include... [Item 18] The method according to item 17, wherein the activation step includes bringing a photolithography solution into contact with a plasma. [Item 19] The method according to item 17 or 18, wherein the activation step includes generating free radicals, solvated electrons, or both in a photolithography solution. [Item 20] The activation step is A step of weakening at least one covalent bond in one or more molecules of the photolithography solution. The method described in any one of items 17-19, including the method described in item 17-19. [Item 21] The activation step is A step of weakening at least one covalent bond in each of several solvated molecules of a photolithography solution, wherein each of the several molecules contains a carbon backbone. The method described in any one of items 17-20, including the method described in item 17-20. [Item 22] The method according to any one of items 18 to 21, wherein at least one covalent bond directly or indirectly attaches an acid group to the carbon backbone. [Item 23] The activation step is A step to stabilize free radicals and / or solvated electrons with cations. The method described in any one of items 19 to 22, including the method described in item 19 to 22. [Item 24] The activation step is A step of stabilizing free radicals and / or solvated electrons with one or more functional groups supported by a carbon backbone. The method described in any one of items 19-23, including the method described in item 19-23. [Item 25] The method according to item 24, wherein one or more functional groups include a cationic functional group. [Item 26] The method according to item 24, wherein one or more functional groups include an anionic functional group. [Item 27] The method according to any one of items 17 to 26, wherein the photolithography solution is selected from the group consisting of a photoresist solution, a developer solution, and a washing solution. [Item 28] The method according to any one of items 17 to 27, wherein the activation step is performed before the processing step. [Item 29] The method according to any one of items 17 to 28, wherein the processing step includes bringing a device component into contact with an activated photolithography solution. [Item 30] The method according to any one of items 17 to 29, wherein the device component includes a semiconductor wafer. [Item 31] The method according to any one of items 17 to 30, wherein the photolithography solution comprises a photoresist solution. [Item 32] The method according to item 31, wherein the photolithography solution comprises a positive-type photoresist. [Item 33] The method according to item 31, wherein the photolithography solution includes a negative-type photoresist. [Item 34] A step of curing a photoresist solution onto a solid layer of photoresist on a semiconductor wafer. And, The method according to any one of items 31 to 33, further comprising the step of trapping free radicals and / or solvated electrons generated by the contact step in the solid layer of the photoresist after the curing step. [Item 35] Steps include exposing a solid layer of photoresist to a pattern of electromagnetic radiation; and A step in which, in response to the exposure step, at least a portion of the electrons and / or solvated electrons of the captured free radicals are released, thereby cleaving the covalent bonds in the solid layer of the photoresist. The method described in item 34, including the method described in item 34. [Item 36] A step to release acid groups in the solid layer of the photoresist in response to the release step. The method described in item 35, including the method described in item 35. [Item 37] The method described in item 35 or 36, wherein electromagnetic radiation includes extreme ultraviolet radiation. [Item 38] The method described in any one of items 35 to 37, wherein electromagnetic radiation exhibits an intensity peak in the wavelength range of 13.3 to 13.7 nm. [Item 39] The method described in any one of items 17-38, wherein the plasma is atmospheric pressure plasma. [Item 40] The method according to any one of items 17 to 39, wherein the contact step is performed in a controlled gas environment. [Item 41] The method according to any one of items 17 to 40, wherein the plasma is a plasma formed by a direct current. [Item 42] The method according to any one of items 17-40, wherein the plasma is a surface wave plasma. [Item 43] A method for manufacturing an integrated circuit, A step of coating at least a portion of a surface device component with a photoresist solution; A step of curing a photoresist solution onto a solid layer of photoresist on a wafer; A step of exposing the solid layer of photoresist to a pattern of electromagnetic radiation; A step of bringing a photoresist into contact with a developing liquid to develop the corresponding pattern in the photoresist; A step of etching the wafer to transfer the pattern from the photoresist to the oxide layer; Step to ashing residual photoresist; The steps of cleaning the wafer with a cleaning solution liquid to remove photoresist residue from the wafer; and The following steps: A step of activating a photoresist solution or components of a photoresist solution with plasma; A step of activating a developing liquid or a component of a developing liquid with plasma; A step of activating the cleaning solution liquid or the components of the cleaning solution liquid with plasma. Steps that perform at least one of the following Methods that include... [Item 44] The method according to item 43, comprising the step of activating a photoresist solution with plasma before or simultaneously with the coating step. [Item 45] The method according to item 43 or 44, comprising the step of activating the developing liquid with plasma before or simultaneously with the contact step. [Item 46] The method according to any one of items 43 to 45, comprising the step of activating the cleaning solution with plasma before or simultaneously with the cleaning step. [Item 47] A method for manufacturing an integrated circuit, A step of coating at least a portion of a surface device component with a photoresist solution; A step of curing a photoresist solution into a solid layer on a wafer; A step of exposing a photoresist to electromagnetic radiation; A step of removing the exposed photoresist by applying a developing solution; A step in which the developer is activated by plasma before or simultaneously with the application step, thereby introducing free radicals and / or solvated electrons into the developer; A step of etching the exposed area of ​​the wafer; A step of ashing residual photoresist; and Step of removing photoresist residue with a liquid cleaning solution. Methods that include... [Item 48] A method for manufacturing an integrated circuit, A step of coating at least a portion of a surface device component with a photoresist solution; A step of curing a photoresist solution into a solid layer on a wafer; A step of exposing a photoresist to electromagnetic radiation; A step of removing the exposed photoresist by applying a developing solution; A step of etching the exposed area of ​​the wafer; Step to ashing residual photoresist; A step of removing photoresist residue with a liquid cleaning solution; and A step in which, before or simultaneously with the removal step, the liquid cleaning solution is activated by plasma, thereby introducing free radicals and / or solvated electrons into the liquid cleaning solution. Methods that include... [Item 49] Prior to the removal step, the first and second components are mixed to form a liquid cleaning solution. The method described in item 48, including the method described in item 48. [Item 50] The activation step is A step to activate the first component with plasma before the mixing step. The method described in item 49, including the method described in item 49. [Item 51] A method for manufacturing an integrated circuit, A step of coating at least a portion of a surface device component with a photoresist solution; A step of curing a photoresist solution into a solid layer on a wafer; A step of exposing a photoresist to electromagnetic radiation; A step of removing the exposed photoresist by applying a developing solution; A step of etching the exposed area of ​​the wafer; Step to ashing residual photoresist; A step of removing photoresist residue with a liquid cleaning solution; and A step in which, before or simultaneously with the coating step, the photoresist solution or components of the photoresist solution are activated by plasma, thereby introducing free radicals and / or solvated electrons into the photoresist solution or components of the photoresist solution. Methods that include... [Item 52] A method for manufacturing an integrated circuit, A step of coating at least a portion of a surface device component with a photoresist solution; A step of curing a photoresist solution into a solid layer on a wafer; A step of exposing a photoresist to electromagnetic radiation; A step of removing the exposed photoresist by applying a developing solution; A step of etching the exposed area of ​​the wafer; Step to ashing residual photoresist; A step of removing photoresist residue with a liquid cleaning solution; and A step in which, before or simultaneously with the application step, the developer liquid or components of the developer liquid are activated by plasma, thereby introducing free radicals and / or solvated electrons into the developer liquid or components of the developer liquid. Methods that include... [Item 53] A method for manufacturing an integrated circuit, A step of coating at least a portion of a surface device component with a photoresist solution; A step of curing a photoresist solution into a solid layer on a wafer; A step of exposing a photoresist to electromagnetic radiation; A step of removing the exposed photoresist by applying a developing solution; A step of etching the exposed area of ​​the wafer; Step to ashing residual photoresist; A step of removing photoresist residue with a liquid cleaning solution; and A step in which, before or simultaneously with the removal step, the liquid cleaning solution or components of the liquid cleaning solution are activated by plasma, thereby introducing free radicals and / or solvated electrons into the liquid cleaning solution or components of the liquid cleaning solution. Methods that include...

Claims

1. Non-aqueous liquid media; and At least one reactive chemical species generated by bringing the surface of a non-aqueous liquid medium into contact with plasma. A plasma activating solution containing, The aforementioned plasma activating solution is a photolithography solution. The photolithography solution is selected from the group consisting of a photoresist solution, a developer solution, and a washing solution. A plasma activating solution comprising a plurality of non-aqueous liquid media brought into contact with plasma.

2. The plasma activating solution according to claim 1, wherein at least one reactive chemical species comprises a free radical, a solvated electron, or both.

3. The plasma activating solution according to claim 1, comprising 5% by weight or less of water.

4. The plasma activating solution according to claim 1, comprising 3% by weight or less of water.

5. The plasma activating solution according to claim 1, comprising 2% by weight or less of water.

6. The plasma activating solution according to claim 1, comprising 1% by weight or less of water.

7. The plasma activating solution according to claim 1, comprising 0.1% by weight or less of water.

8. The plasma activating solution according to claim 1, comprising 0.01% by weight or less of water.

9. The plasma activating solution according to claim 1, comprising 0.001% by weight or less of water.

10. A plasma activating solution according to any one of claims 1 to 9, comprising free radicals, solvated electrons, or both.

11. A plasma activating solution according to any one of claims 1 to 10, comprising a plurality of solvation molecules, each of which comprises a carbon main chain.

12. The plasma activating solution according to claim 11, wherein each of the plurality of molecules contains at least one covalent bond that directly or indirectly attaches an acid group to a carbon main chain.

13. A plasma activating solution according to any one of claims 1 to 12, comprising ionic chemical species that stabilize free radicals and / or solvated electrons, or more such species.

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