Exposure method and semiconductor device
By forming an ion supplementary layer at the bottom of the photoresist layer, the problem of uneven ions diffusion at the bottom of the photoresist layer is solved, the photolithography pattern morphology is optimized, and the exposure accuracy and device performance are improved.
Patent Information
- Application Number
- CN202510866117.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-25
- Publication Date
- 2025-09-05
AI Technical Summary
In the existing lithography technology, uneven diffusion of ions at the bottom of the photoresist layer leads to low photolithography morphology accuracy, affecting device performance.
An ion supplementary layer is formed on the substrate, and ions in the ion supplementary layer are used to diffuse towards the bottom of the photoresist layer to compensate for the ion concentration at the bottom of the photoresist layer and make it uniform.
The problem of uneven ion concentration at the bottom of the photoresist layer was solved, the photolithography pattern was optimized, and the exposure accuracy and device performance were improved.
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Figure CN120595539A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to an exposure method and a semiconductor device. Background Art
[0002] Photolithography is a common process in semiconductor manufacturing. It uses light to transfer the pattern from a mask to a photoresist, triggering a photochemical reaction in the pattern. This pattern is then left on the photoresist after development, preparing it for subsequent processes like etching or ion implantation. Currently, more advanced photolithography machines use chemical amplification resins to improve their output efficiency, but existing exposure methods suffer from inaccurate lithography topography.
[0003] See also Figure 1 Taking positive photoresist as an example, the photoresist layer coated on the substrate 100 is divided into a non-illuminated area 110 and an illuminated area 111. The chemically amplified resist in the illuminated area 111 undergoes a photochemical reaction after being illuminated, and produces a small amount of photoacid. A small amount of photoacid will diffuse to the surroundings within a certain range. Figure 2 As shown, after the exposure process, and in the process of performing the post-exposure bake (PEB) process, the resin in the illumination area 111 falls off the hanging groups under the catalysis of high temperature and light acid and decomposes more acid ions. These acid ions also can continuously diffuse toward the periphery, and the acid ion diffusion speeds in different areas are different. Wherein, the acid ions located in the middle area of the illumination area 111 diffuse evenly; that is, the speed of diffusion from here to the outside is basically the same as that of diffusion from the outside, so that the acid ion concentration located in the middle area of the illumination area 111 is uniform. And the acid ions located at the edge position of the illumination area 111, i.e., the boundary side of the illumination area 111 and the non-illumination area 110 and the boundary side of the illumination area 111 and the substrate 100, have only half the speed of diffusion from the outside to the inside as compared to the outside diffusion speed, resulting in a lower acid ion concentration at the edge position. In addition, the diffusion rate of acid ions from the outside to the inside at the corner A at the bottom of the illuminated area 111, that is, at the interface between the illuminated area 111, the non-illuminated area 110 and the substrate 100, is only one-fourth of the diffusion rate from the inside to the outside, which makes the acid ion concentration lower, and the acid ion distribution at the bottom of the illuminated area 111 is uneven, which seriously affects the decomposition reaction of the resin in the photoresist during the PEB process.
[0004] Based on this, Figure 3As shown, after the PEB process, the chemically amplified glue is cleaned with an alkaline developer, and the glue in the illuminated area 111 is substantially dissolved. However, due to the very low acid ion concentration at the corner A, some of the glue at the corner A of the illuminated area 111 remains undissolved, resulting in photolithographic residue F1. This seriously affects the accuracy of the photolithographic topography and negatively impacts subsequent processes such as ion implantation and etching.
[0005] Similarly, if Figure 4 As shown, in the negative photoresist, there is an alkaline substance in the illuminated area 111, and after being excited by light, it will catalyze the generation of more alkali ions to neutralize the acid ions in the illuminated area 111. The distribution of the alkali ions is the same as that in the positive photoresist, and there is also the problem of uneven diffusion of the bottom alkali ions. Wherein, the alkali ion concentration at the bottom corner of the illuminated area 111 of the negative photoresist is low, so the neutralization ability of the acid ions is very weak, resulting in a high acid ion concentration at the bottom corner of the illuminated area 111, so that after development, the bottom corner of the illuminated area 111 of the negative photoresist will be excessively dissolved, resulting in a morphological defect of pit F2. This photolithographic morphology will also increase the risk of photoresist collapse (peeling), cause adverse effects on subsequent processes, and affect device performance.
[0006] Therefore, a new exposure method is urgently needed to solve the above technical problems. Summary of the Invention
[0007] The object of the present invention is to provide an exposure method and a semiconductor device to solve at least one of the technical problems of how to alleviate the influence of uneven ion diffusion at the bottom of the illumination area on the exposure morphology of the photoresist, how to improve process accuracy, and how to improve device performance.
[0008] In order to solve the above technical problems, the present invention provides an exposure method, comprising:
[0009] providing a substrate;
[0010] forming an ion replenishment layer on a top layer of the substrate and / or a top surface of the substrate;
[0011] forming a photoresist layer on the surface of the ion replenishment layer, and sequentially performing an exposure process and a baking process on the photoresist layer; simultaneously, ions in the ion replenishment layer diffuse toward the bottom of the photoresist layer so that the concentration of the ions at the bottom of the illuminated area of the photoresist layer is uniform;
[0012] A developing process is performed on the photoresist layer.
[0013] Optionally, in the exposure method, the photoresist layer includes a positive photoresist, and the material of the ion replenishment layer includes a photoacid generator.
[0014] Optionally, in the exposure method, the acid ions in the ion replenishment layer diffuse to the bottom of the photoresist layer, so that the concentration of the acid ions in the bottom of the illuminated area of the photoresist layer is uniform at least during the baking process.
[0015] Optionally, in the exposure method, the photoresist is doped with an alkali neutralizer, and the concentration of the alkali neutralizer at the bottom of the photoresist layer is lower than the concentration of the alkali neutralizer in other areas of the photoresist layer.
[0016] Optionally, in the exposure method, the photoresist layer includes a negative photoresist, and the material of the ion replenishment layer includes a photobase generator.
[0017] Optionally, in the exposure method, the alkali ions in the ion replenishment layer diffuse to the bottom of the photoresist layer, so that the concentration of the alkali ions in the bottom of the illuminated area of the photoresist layer is uniform at least during the baking process.
[0018] Optionally, in the exposure method, the process of forming the ion replenishment layer on the top layer of the substrate includes:
[0019] The top layer of the substrate includes an anti-reflection layer, and a material solution of the ion replenishment layer with a preset concentration is doped in the process of forming the anti-reflection layer, so that the ion replenishment layer is mixed and formed in the anti-reflection layer.
[0020] Optionally, in the exposure method, the process of forming the ion replenishment layer on the top surface of the substrate includes:
[0021] Atomizing the material solution of the ion replenishment layer by using an inert gas, and then spraying the atomized material solution onto the top surface of the substrate;
[0022] The material solution of the ion replenishing layer is dried to form the ion replenishing layer.
[0023] Optionally, in the exposure method, during the diffusion of ions in the ion replenishment layer toward the bottom of the photoresist layer, the thickness of the ion diffusion area in the photoresist layer is less than the thickness of the remaining area of the photoresist layer that has not been diffused by the ions.
[0024] Based on the same inventive concept, the present invention also provides a semiconductor device, which is manufactured using the exposure method.
[0025] In summary, the present invention provides an exposure method and semiconductor device. Compared to the prior art, the exposure method forms an ion replenishment layer on the top layer and / or the top surface of the substrate before forming the photoresist layer. The ion replenishment layer compensates for the ion concentration at the bottom of the photoresist layer, thereby resolving the problem of low ion concentration at the bottom of the photoresist layer due to uneven ion diffusion in the photoresist layer. This ensures a uniform ion concentration at the bottom of the illuminated area of the photoresist layer, effectively avoiding photolithographic morphological defects caused by uneven ion diffusion within the illuminated area. This method facilitates optimization of the photolithographic pattern morphology, improving exposure accuracy, and enhancing device performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Those skilled in the art will appreciate that the drawings are provided for a better understanding of the present invention, but do not constitute any limitation on the scope of the present invention.
[0027] Figure 1 This is a schematic diagram of the diffusion of acid ions in the illuminated area during the exposure process in the prior art.
[0028] Figure 2 This is a schematic diagram of the diffusion of acid ions in the illuminated area during the post-baking process in the prior art.
[0029] Figure 3 This is a schematic diagram of photoresist residues that appear after positive photoresist development in the prior art.
[0030] Figure 4 It is a schematic diagram of pits appearing after negative photoresist is developed in the prior art.
[0031] Figure 5 4 is a flow chart of an exposure method in an embodiment of the present invention.
[0032] Figure 6 Schematic diagram of the position of the anti-reflection layer in an embodiment of the present invention.
[0033] Figure 7 Schematic diagram of forming an ion replenishment layer by a spraying process in an embodiment of the present invention.
[0034] Figure 8 Schematic diagram of an embodiment of the present invention in which the ion replenishment layer and the anti-reflection layer are integrated into one.
[0035] Figure 9 Schematic diagram of a semiconductor structure in an exposure process according to an embodiment of the present invention.
[0036] Figure 10 Schematic diagram of uniform ion diffusion during the baking process in an embodiment of the present invention.
[0037] Figure 11 Schematic diagram of the positive photoresist layer after development in an embodiment of the present invention.
[0038] Figure 12 Schematic diagram of the negative photoresist layer after development in an embodiment of the present invention.
[0039] And, in the accompanying drawings:
[0040] 100-substrate; 110-non-illuminated area; 111-illuminated area;
[0041] 200 - substrate; 200a - anti-reflection layer; 201 - ion replenishment layer; 202 - non-illuminated area; 203 - illuminated area;
[0042] 300-reaction chamber; 301-wafer carrier;
[0043] F1-photolithography residue; F2-pit; A-corner. DETAILED DESCRIPTION
[0044] In order to make the objects, advantages and features of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis required to be shown in each drawing is different, and sometimes different scales are used. It should also be understood that, unless otherwise specified or indicated, the terms "first", "second", "third" and the like in the specification are only used to distinguish between the various components, elements, steps, etc. in the specification, and are not used to represent the logical relationship or sequential relationship between the various components, elements, steps, etc.
[0045] See also Figure 5 , this embodiment provides an exposure method, including:
[0046] Step 1 S10: providing a substrate;
[0047] Step 2 S20: forming an ion supplement layer on the top layer of the substrate and / or on the top surface of the substrate;
[0048] Step 3 S30: forming a photoresist layer on the surface of the ion replenishment layer, and sequentially performing an exposure process and a baking process on the photoresist layer; at the same time, ions in the ion replenishment layer diffuse toward the bottom of the photoresist layer, so that the concentration of the ions at the bottom of the illuminated area of the photoresist layer is uniform;
[0049] Step 4 S40: performing a development process on the photoresist layer.
[0050] Based on this, the exposure method provided in this embodiment is to form an ion replenishment layer on the top layer of the substrate and / or on the top surface of the substrate before forming the photoresist layer, so as to use the ion replenishment layer to compensate for the ion concentration at the bottom of the photoresist layer, thereby solving the problem of low ion concentration at the bottom due to uneven ion diffusion in the photoresist layer, so that the ion concentration at the bottom of the illuminated area of the photoresist layer is uniform, effectively avoiding the photolithography morphology defects caused by uneven diffusion of ions in the illuminated area, which is beneficial to optimizing the photolithography pattern morphology and improving exposure accuracy and device performance.
[0051] The following combination Figures 5 to 12 , specifically describe the exposure method provided in this embodiment.
[0052] Specifically, the exposure method includes:
[0053] Step 1 S10: Please refer to Figure 6 , providing a substrate 200.
[0054] The substrate 200 provides an operating platform for subsequent processes. It can be any base material known to those skilled in the art for carrying semiconductor integrated circuit components. It can be a bare chip, a wafer processed by an epitaxial growth process, or a circuit layer with devices formed on it.
[0055] Furthermore, the top layer of the substrate 200 includes an anti-reflection layer 200a, which is used to reduce reflection during the exposure process, improve lithography resolution, avoid pattern distortion and scattering caused by reflected light, and enhance lithography pattern quality. Optionally, the anti-reflection layer 200a may be made of, but is not limited to, polyimide, silicon nitride, silicon oxide, titanium oxide, and zinc oxide.
[0056] Step 2 S20: Please refer to Figures 7 to 9 , an ion supplement layer 201 is formed on the top layer of the substrate 200 and / or on the top surface of the substrate 200 .
[0057] The material of the ion replenishment layer 201 varies depending on the properties of the photoresist. Optionally, when the photoresist layer is a positive photoresist, the material of the ion replenishment layer 201 includes a photoacid generator (PAG). Upon exposure to light, the PAG undergoes a photochemical reaction to produce photoacid, which catalyzes the decomposition of the resin in the photoresist and produces more acid ions during the PEB process. Therefore, the provision of the ion replenishment layer 201 can increase the photoacid concentration at the bottom of the photoresist layer during subsequent exposure and baking processes, ensuring a uniform acid ion concentration at the bottom, effectively avoiding the impact of uneven acid ion diffusion on the photolithographic morphology, and thus fully dissolving the bottom structure of the photoresist layer in the illuminated area 203 during the development process, alleviating the problem of photolithographic residue and optimizing the morphology of the patterned photoresist layer.
[0058] When the photoresist layer is a negative photoresist, the material of the ion replenishment layer 201 includes a photobase generator (PBG). Upon exposure to light, the PBG absorbs photons and releases alkali ions, thereby neutralizing nearby acid ions in the photoresist layer. Therefore, the provision of the ion replenishment layer 201 can increase the alkali ion concentration at the bottom of the photoresist layer during subsequent exposure and baking processes, ensuring a uniform alkali ion concentration at the bottom and effectively preventing the impact of uneven alkali ion diffusion on the photolithographic morphology. Consequently, during the PEB process, the alkali ions can fully neutralize the acid ions at the bottom of the illuminated region 203 in the photoresist layer, preventing pit defects and optimizing the morphology of the patterned photoresist layer.
[0059] Furthermore, in this embodiment, the ion replenishment layer 201 can be formed directly on the top surface of the substrate 200, or can be doped into the top structure of the substrate 200; or, the ion replenishment layer 201 can be partially formed on the top surface of the substrate 200 and partially doped into the anti-reflection layer 200a. The specific formation process of the ion replenishment layer 201 is not limited in this embodiment.
[0060] For example, Figure 7As shown, the process of directly forming the ion replenishment layer 201 on the top surface of the substrate 200 includes: first, placing the substrate 200 on a wafer carrier 301 in a reaction chamber 300; then, introducing an inert gas and a material solution of the ion replenishment layer 201 into the reaction chamber 300; using the inert gas to atomize the material solution of the ion replenishment layer 201; and then spraying the atomized material solution onto the top surface of the substrate 200. Subsequently, drying the material solution of the ion replenishment layer 201 to form the ion replenishment layer 201. Optionally, the inert gas is nitrogen, which is used to atomize the photoacid generator or the photobase generator without affecting the chemical composition of the photoacid generator or the photobase generator.
[0061] It should be noted that before applying the photoresist layer and performing the exposure process, the surface of the substrate 200 can be treated. For example, a layer of hexamethyldisilazane can be sprayed on the surface of the substrate 200 to change it from hydrophobic to hydrophilic, thereby improving the adhesion of the photoresist to the substrate 200 surface and preventing the photoresist from collapsing. Optionally, the ion replenishment layer 201 can be formed simultaneously during the surface treatment process. Of course, the ion replenishment layer 201 can also be formed before or after the surface treatment, and this embodiment does not specifically limit this.
[0062] Another example, Figure 8 As shown, the process of forming the ion replenishment layer 201 on the top layer of the substrate 200 can be to dope a material solution of the ion replenishment layer 201 at a predetermined concentration during the process of forming the anti-reflection layer 200a, so that the ion replenishment layer 201 is mixed and formed in the anti-reflection layer 200a. In other words, the ion replenishment layer 201 and the anti-reflection layer 200a are integrated into a single film layer, thereby eliminating the step of separately forming the ion replenishment layer 201 and streamlining the process flow.
[0063] Step 3 S30: Please refer to Figure 9 and Figure 10 , a photoresist layer is formed on the surface of the ion replenishment layer 201, and an exposure process and a baking process are sequentially performed on the photoresist layer; at the same time, the ions in the ion replenishment layer 201 diffuse toward the bottom of the photoresist layer so that the concentration of the ions at the bottom of the illuminated area 203 in the photoresist layer is uniform.
[0064] As can be seen from the above, the uneven diffusion of the inherent ions in the photoresist layer will lead to a low ion concentration at its bottom, thereby affecting the photolithography effect. The exposure method provided in this embodiment utilizes the added ion replenishment layer 201 to provide compensating ions toward the bottom of the photoresist layer, thereby solving the problem of low ion concentration. Specifically, when the photoresist layer is a positive photoresist, the material of the ion replenishment layer 201 includes a photoacid generator; when the photoresist layer is a negative photoresist, the material of the ion replenishment layer 201 includes a photobase generator. Based on this, when a photoresist layer is formed on the surface of the ion replenishment layer 201, the solvent in the photoresist layer will dissolve the ion replenishment layer 201, thereby causing the ions in the ion replenishment layer 201 to diffuse toward the bottom of the photoresist layer. That is, the acid ions in the photoacid generator diffuse toward the bottom of the positive photoresist to compensate for the acid ion concentration at the bottom of the photoresist; the alkali ions in the photobase generator diffuse toward the bottom of the negative photoresist to compensate for the alkali ion concentration at the bottom of the photoresist, thereby effectively alleviating the problem of uneven ion diffusion at the bottom of the illuminated area 203, and making the concentration of the ions at the bottom of the illuminated area 203 uniform.
[0065] Furthermore, after the photoresist layer is formed on the surface of the ion replenishment layer 201, the photoresist layer needs to be subjected to an exposure process and a baking process in sequence. During the exposure process and the baking process, the ions in the ion replenishment layer 201 continue to diffuse toward the bottom of the photoresist layer.
[0066] Specifically, during the exposure process, based on the graphical design of the mask, some areas of the photoresist layer are exposed to light, while others are not. The areas that are not exposed to light are designated as non-illuminated areas 202, and the areas that are exposed to light are designated as illuminated areas 203. Taking positive photoresist as an example, the photoacid in the illuminated areas 203, after being excited by light, catalyzes the production of a small amount of acid ions. These acid ions continuously diffuse within the illuminated areas 203 and undergo a decomposition reaction with the resin in the photoresist. The pendant groups fall off and release more acid ions, making the reacted photoresist easily dissolveable and removed by the developer. When the baking process is performed after the exposure is complete, the resin in the photoresist layer, under the action of high temperature and catalysis by the photoacid, produces a large amount of acid ions. These acid ions diffuse toward the periphery to further catalyze the decomposition reaction of the resin in other areas of the photoresist layer. However, due to the difference in diffusion speed between the inside and outside, the acid ion concentration is lower at the bottom corner of the illuminated area 203, resulting in uneven acid ion concentration at the bottom of the illuminated area 203. Therefore, this embodiment adds a thin ion replenishment layer 201 at the bottom of the photoresist layer. The ions in the ion replenishment layer 201 diffuse toward the bottom of the photoresist layer, thereby making the acid ion concentration at the bottom of the illuminated area 203 uniform, effectively avoiding the problem of photolithography residue caused by uneven acid ion concentration, and is conducive to optimizing the photolithography pattern morphology and improving exposure accuracy.
[0067] Similarly, when the photoresist layer is a negative resist, the photobase generator in the illuminated region 203, upon being excited by light, catalytically generates a large number of alkali ions, which neutralize the acid ions in the illuminated region 203 and prevent the resin in the photoresist from decomposing and modifying under the catalysis of the acid ions. Furthermore, because the ion replenishment layer 201 diffuses a large number of alkali ions toward the bottom of the illuminated region 203, the problem of uneven diffusion of the inherent alkali ions in the illuminated region 203 at the bottom and corners is effectively avoided. This ensures a uniform concentration of alkali ions at the bottom of the illuminated region 203 during the baking process, facilitating the solidification of the colloidal structure in the illuminated region 203 during the subsequent development process, preventing excessive dissolution, and facilitating the optimization of the photolithographic pattern morphology and improving exposure accuracy.
[0068] The diffusion of ions in the ion replenishment layer 201 is limited to the bottom of the photoresist layer. Furthermore, the thickness of the ion-diffused region in the photoresist layer is less than the thickness of the remaining region of the photoresist layer that has not been diffused. In other words, there is no interference with other regions of the photoresist layer.
[0069] Furthermore, the positive photoresist provided in this embodiment is doped with an alkali neutralizer. The alkali neutralizer can react with the photoacid in the photoresist layer to neutralize the photoacid, thereby preventing the photoacid from diffusing to a distant location and affecting the photolithographic morphology. Optionally, during the formation of the photoresist layer, the doping concentration of the alkali neutralizer is adjusted so that the alkali neutralizer concentration at the bottom of the photoresist layer is less than the alkali neutralizer concentration in other areas of the photoresist layer, thereby reducing the acid-base neutralization reaction at the bottom of the illuminated area 203 and increasing the acid ion concentration at the bottom of the illuminated area 203, which is conducive to balancing the acid ion concentration at the bottom of the illuminated area 203 and alleviating the photolithographic residue problem caused by uneven acid ion diffusion.
[0070] Step 4 S40: Please refer to Figure 11 and Figure 12 , perform a developing process on the photoresist layer. That is, use a developer to clean the photoresist layer so that the illuminated area 203 in the positive photoresist is dissolved and removed, leaving only the non-illuminated area 202 (such as Figure 11 Alternatively, the non-illuminated area 202 in the negative photoresist is dissolved and removed, leaving only the illuminated area 203 (as shown in FIG. Figure 12 shown).
[0071] It should be noted that the ion replenishment layer 201 provided in this embodiment is very thin. Upon contact with the photoresist layer, it is substantially dissolved by the solvent in the photoresist layer, causing ions to diffuse to the bottom of the photoresist layer. Therefore, after the development process, the ion replenishment layer 201 is substantially consumed and does not affect subsequent processes. Furthermore, this embodiment does not limit the ion concentration in the ion replenishment layer 201; it can be determined based on factors such as the type, thickness, aspect ratio, and degree of photoresist residue or photoresist pitting during the actual process.
[0072] Based on the same concept, this embodiment further provides a semiconductor device, which is manufactured using the above-mentioned exposure method, has a better photolithography morphology and high process precision, thereby improving device performance.
[0073] In summary, this embodiment provides an exposure method and semiconductor device. The exposure method forms an ion replenishment layer 201 on the top layer and / or the top surface of the substrate 200 before forming the photoresist layer. The ion replenishment layer 201 compensates for the ion concentration at the bottom of the photoresist layer, thereby resolving the problem of low ion concentration at the bottom of the photoresist layer due to uneven ion diffusion in the photoresist layer. This ensures a uniform ion concentration at the bottom of the illuminated region 203, effectively avoiding photolithographic morphological defects caused by uneven ion diffusion within the illuminated region 203. This facilitates optimization of the photolithographic pattern morphology, improving exposure accuracy, and enhancing device performance.
[0074] Furthermore, it should be recognized that although the present invention has been disclosed above with reference to preferred embodiments, the above embodiments are not intended to limit the present invention. Any person skilled in the art can utilize the above disclosed technical content to make many possible changes and modifications to the technical solution of the present invention, or modify it into equivalent embodiments with equivalent variations, without departing from the scope of the technical solution of the present invention. Therefore, any simple modifications, equivalent variations, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the technical solution of the present invention, shall still fall within the scope of protection of the technical solution of the present invention.
Claims
1. An exposure method, characterized in that: include: providing a substrate; forming an ion replenishment layer on a top layer of the substrate and / or a top surface of the substrate; forming a photoresist layer on the surface of the ion replenishment layer, and sequentially performing an exposure process and a baking process on the photoresist layer; simultaneously, ions in the ion replenishment layer diffuse toward the bottom of the photoresist layer so that the concentration of the ions at the bottom of the illuminated area of the photoresist layer is uniform; A developing process is performed on the photoresist layer.
2. The exposure method according to claim 1, wherein The photoresist layer includes positive photoresist, and the material of the ion replenishing layer includes photoacid generator.
3. The exposure method according to claim 2, wherein: The acid ions in the ion replenishment layer diffuse to the bottom of the photoresist layer, so that at least during the baking process, the concentration of the acid ions in the bottom of the illuminated area of the photoresist layer is uniform.
4. The exposure method according to claim 2 or 3, wherein: The photoresist is doped with an alkali neutralizer, and the concentration of the alkali neutralizer at the bottom of the photoresist layer is lower than the concentration of the alkali neutralizer in other areas of the photoresist layer.
5. The exposure method according to claim 1, wherein The photoresist layer includes a negative photoresist, and the material of the ion replenishing layer includes a photobase generator.
6. The exposure method according to claim 5, wherein: The alkali ions in the ion replenishment layer diffuse to the bottom of the photoresist layer, so that at least during the baking process, the concentration of the alkali ions in the bottom of the illuminated area of the photoresist layer is uniform.
7. The exposure method according to claim 1, wherein The process of forming the ion replenishment layer on the top layer of the substrate includes: The top layer of the substrate includes an anti-reflection layer, and a material solution of the ion replenishment layer with a preset concentration is doped in the process of forming the anti-reflection layer, so that the ion replenishment layer is mixed and formed in the anti-reflection layer.
8. The exposure method according to claim 1, wherein The process of forming the ion replenishment layer on the top surface of the substrate includes: Atomizing the material solution of the ion replenishment layer by using an inert gas, and then spraying the atomized material solution onto the top surface of the substrate; The material solution of the ion replenishing layer is dried to form the ion replenishing layer.
9. The exposure method according to claim 1, wherein During the diffusion of ions in the ion supplement layer toward the bottom of the photoresist layer, the thickness of the ion-diffused region in the photoresist layer is smaller than the thickness of the remaining region of the photoresist layer into which the ions have not diffused.
10. A semiconductor device, characterized in that: The semiconductor device is manufactured by using the exposure method according to any one of claims 1 to 9.