阅读说明：本技术 一种芯片制程中环境友好的定影方法 (Environment-friendly fixing method in chip manufacturing process ) 是由 崔恩密 王爱明 于 2021-08-11 设计创作，主要内容包括：本发明提供了一种芯片制程中环境友好的定影方法,包括：显影去除硅片上未曝光的光刻胶,定影除去上述工序中残留显影液及少量杂质。所述显影液为芯片行业通用显影液,即碳氢溶剂,显影温度25℃,显影时间一分钟,定影液为纯水,或纯水中复配少许醇类溶剂、醇醚类溶剂、醇醚酯溶剂、酮类溶剂及有一定挥发性的表面活性剂、非离子表面活性剂。该发明抛弃了目前行业中通用的常规有机定影液技术,而采用水性物质作为定影液,不但大大降低了常规定影液的采购成本及由此产生的危险废弃物处理成本,而且减少了芯片行业VOC的排放量,为环境友好、环保可持续发展做出了一定贡献,具有较高的经济效益和社会效益。(The invention provides an environment-friendly fixing method in a chip manufacturing process, which comprises the following steps: and developing to remove the unexposed photoresist on the silicon wafer, and fixing to remove the residual developing solution and a small amount of impurities in the working procedure. The developing solution is a developing solution commonly used in the chip industry, namely a hydrocarbon solvent, the developing temperature is 25 ℃, the developing time is one minute, the fixing solution is pure water, or a little alcohol solvent, alcohol ether ester solvent, ketone solvent, surfactant with certain volatility and nonionic surfactant are compounded in the pure water. The invention abandons the common conventional organic photographic fixing solution technology in the industry at present, adopts the water-based substance as the photographic fixing solution, not only greatly reduces the purchase cost of the conventional photographic fixing solution and the treatment cost of hazardous wastes generated by the conventional photographic fixing solution, but also reduces the discharge amount of VOC in the chip industry, makes certain contribution to the environment-friendly and environment-friendly sustainable development, and has higher economic benefit and social benefit.)

1. An environmentally friendly fixing method in a chip process, comprising the following components: pure water, deionized water, its characterized in that: the fixing solution is pure water or deionized water (resistance is 10)¹⁸Megohm), compounding a little of the following compounds and alcohol solvents in water: methanol, ethanol, isopropanol, butanol, isobutanol, isoamyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, alcohol ether solvents: ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol butyl ether, dipropylene glycol methyl ether, alcohol ether esters: propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, diethylene glycol butyl ether acetate, ketone solvents: acetone, butanone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone, nonionic surfactant: polyoxyethylene type APEO, AEO.

2. An environment-friendly fixing method in a chip manufacturing process specifically comprises the following steps:

step 1: and (3) gluing, namely spin-coating on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

Step 2: pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

And step 3: and (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

And 4, step 4: and (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

And 5: and developing with a conventional developing solution at 25 ℃ for 1min to form a photoetching pattern.

Step 6: and (3) fixing, namely washing the developed silicon wafer by adopting a mixture compounded by 99.5 kg of pure water and 0.5 kg of isopropanol to remove the developing solution and impurities remained on the surface of the adhesive film.

And 7: and (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

And 8: etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

And step 9: and (3) removing the photoresist, namely removing the photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish the primary photoetching process.

Technical Field

The invention relates to the technical field of chip manufacturing, in particular to an environment-friendly fixing method in a chip manufacturing process.

Background

The photoetching process is the core of the chip manufacturing process, and a proper photoresist and photoetching process conditions matched with the photoresist are selected to achieve a good product photoetching effect.

The cyclized rubber negative photoresist has the characteristics of good adhesion, quick light sensitivity, strong acid resistance and the like, and particularly has the advantage of resisting the corrosion of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid mixtures, so that the photoresist is widely applied to the chip industry for forming a required etching shape, in the using process of the photoresist, an unexposed part needs to be removed by using a developing solution, and then the developing solution and residual trace impurities are removed by using a fixing solution, which is generally called a developing and fixing process. In the chip manufacturing process, butyl acetate is usually selected as the fixing solution, and the fixing solution has the advantages of fast developer removal, easy volatilization, no residue, and the functions of protecting and shaping photoresist, and is widely applied to the chip manufacturing industry. However, the compound has the disadvantages of strong odor and strong irritation, and in addition, the waste fixing solution generated by the compound is generally treated by adopting a mode of incineration and the like, so that the environmental load is increased, and the compound has the following characteristics: 200510028668.8, it is characterized in that a mixed strain composed of actinomycetes and saccharomycetes and a carrier are made into a microbial inoculum, then the microbial inoculum is mixed with the waste developing solution and the waste fixing solution to stack, the temperature, humidity and time of stacking are controlled, after the stacking is finished, the microbial inoculum for processing the waste developing solution can be directly used as a fertilizer, but the method needs a larger space to carry out microbial fermentation, and the fermentation process can generate carbon dioxide on one hand, increase greenhouse gas emission, and generate waste water on the other hand. The traditional organic fixing technology inevitably causes environmental pollution and VOC storage increase caused by the fact that fixing liquid volatilizes into the atmosphere, and is not beneficial to environmental protection and sustainable development of the society. The water-based fixing technology contributes to the positive force for protecting the environment.

Disclosure of Invention

The invention aims to replace the general technology of taking an organic solvent as a fixer in the current industry; by adopting the water-based fixing technology, the volatilization of organic matters is reduced, the acquisition and purchase cost of the organic fixing solution is reduced, the storage amount of dangerous waste generated by the acquisition and purchase cost and the corresponding treatment cost are reduced, and the water-based fixing technology has obvious social benefit and economic benefit.

In order to achieve the purpose, the invention provides the following technical scheme: an environment-friendly fixing method in a chip manufacturing process, a photoetching process for manufacturing a chip, comprises the following steps:

1. and (3) coating glue, namely spin-coating a common negative photoresist product on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

2. Pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

3. And (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

4. And (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

5. And developing with conventional developer at 25 deg.c for 1min to form photoetching pattern.

6. And (3) fixing, namely washing the developed silicon wafer by adopting a mixture compounded by 99.5 kg of pure water and 0.5 kg of isopropanol to remove the developing solution and impurities remained on the surface of the adhesive film.

7. And (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

8. Etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

9. And (3) removing the photoresist, namely removing the photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish the primary photoetching process.

A photoetching process for manufacturing a chip comprises the following steps:

1. and (3) gluing, namely spin-coating a negative photoresist (mixed with glass powder and uniformly mixed) on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

2. Pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

3. And (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

4. And (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

5. And developing with a conventional developing solution at 25 ℃ for 1min to form a photoetching pattern.

6. And (3) fixing, namely washing the developed silicon wafer by adopting a mixture compounded by 99 kg of pure water and 1 kg of ethylene glycol monomethyl ether to remove the developing solution and impurities remained on the surface of the adhesive film.

7. And (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

8. Etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

9. And (4) removing the photoresist, namely removing the photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish the secondary photoetching process.

A photoetching process for manufacturing a chip comprises the following steps:

1. and (3) coating glue, namely spin-coating a negative photoresist on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

2. Pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

3. And (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

4. And (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

5. And developing with conventional developer at 25 deg.c for 1min to form photoetching pattern.

6. And (3) fixing, namely washing the developed silicon wafer by adopting 99.9 kg of pure water and FS-61/720.1 kg of surfactant to remove the developing solution and impurities remained on the surface of the adhesive film.

7. And (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

8. Etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

9. Removing photoresist, namely removing photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish three times of photoetching processes,

compared with the prior art, the invention has the beneficial effects that: the invention abandons the common organic fixing solution technology in the industry at present, and adopts water-based substances as the fixing solution, thereby not only greatly reducing the purchase cost of the common fixing solution and the treatment cost of dangerous wastes generated by the conventional fixing solution, but also reducing the discharge amount of VOC in the chip industry, making certain contribution to the sustainable development of environmental protection, and having higher economic benefit and social benefit.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The preferred embodiments are described for the purpose of illustration and explanation only and are not intended to be limiting of the invention.

EXAMPLE one (yellow light)

A photoetching process for manufacturing a chip comprises the following steps:

1. and (3) coating glue, namely spin-coating a common negative photoresist product on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

2. Pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

3. And (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

4. And (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

5. And developing with conventional developer at 25 deg.c for 1min to form photoetching pattern.

6. And (3) fixing, namely washing the developed silicon wafer by adopting a mixture compounded by 99.5 kg of pure water and 0.5 kg of isopropanol to remove the developing solution and impurities remained on the surface of the adhesive film.

7. And (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

8. Etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

9. And (3) removing the photoresist, namely removing the photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish the primary photoetching process.

EXAMPLE two (second yellow light)

A photoetching process for manufacturing a chip comprises the following steps:

1. and (3) gluing, namely spin-coating a negative photoresist (mixed with glass powder and uniformly mixed) on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

2. Pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

3. And (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

4. And (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

5. And developing with a conventional developing solution at 25 ℃ for 1min to form a photoetching pattern.

6. And (3) fixing, namely washing the developed silicon wafer by adopting a mixture compounded by 99 kg of pure water and 1 kg of ethylene glycol monomethyl ether to remove the developing solution and impurities remained on the surface of the adhesive film.

7. And (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

8. Etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

9. And (4) removing the photoresist, namely removing the photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish the secondary photoetching process.

EXAMPLE three (three yellow light)

A photoetching process for manufacturing a chip comprises the following steps:

1. and (3) coating glue, namely spin-coating a negative photoresist on the conventionally cleaned and dried silicon wafer surface, wherein the spin-coating process is 600R/MIN in the first 30 seconds and 3500R/MIN in the last 50 seconds.

2. Pre-baking, after coating, baking on a hot plate at 100 ℃ for 2min to remove the solvent in the adhesive film, and measuring the film thickness to be about 2.5 μm.

3. And (4) exposure, namely ultraviolet exposure, and exposing the silicon wafer through a mask plate.

4. And (5) intermediate baking, namely baking for 6min in a baking oven at 120 ℃ to improve the adhesion between the adhesive film and the silicon wafer substrate.

5. And developing with conventional developer at 25 deg.c for 1min to form photoetching pattern.

6. And (3) fixing, namely washing the developed silicon wafer by adopting 99.9 kg of pure water and FS-61/720.1 kg of surfactant to remove the developing solution and impurities remained on the surface of the adhesive film.

7. And (3) post-baking, namely baking the silicon wafer subjected to fixation in a 160 ℃ baking oven for 30min to remove residual solvent, so that the adhesive film is solidified compactly, and the adhesive force and the corrosion resistance of the adhesive film are improved.

8. Etching, namely etching the silicon substrate by using mixed acid liquid of hydrofluoric acid, nitric acid, sulfuric acid and acetic acid.

9. And (3) removing the photoresist, namely removing the photoresist by using 98 wt% concentrated sulfuric acid at 80 ℃ to finish the three-time photoetching process.

The terms "central," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated based on the orientation or positional relationship shown for ease of description of the invention only, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the scope of the invention.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes, modifications, equivalents, improvements and the like can be made therein without departing from the spirit and scope of the invention.