CN114706270A - High-toughness silk full-water-based multipurpose photoresist and preparation method thereof - Google Patents

Abstract

The invention provides a high-toughness silk all-water-based multipurpose photoresist and a preparation method thereof, wherein the high-toughness silk all-water-based multipurpose photoresist comprises silk fibroin and aqueous solution extracted from silkworm strains, and the silkworm strains are 4 silkworm strains with excellent silk mechanical properties, which are obtained by respectively utilizing FibH and FibL promoters to specifically regulate and control FibL and P25 endogenous proteins; a preparation method of a high-toughness silk full-water-based multipurpose photoresist comprises the following steps of S1: extracting silk fibroin from silkworm varieties obtained by specifically regulating and controlling FibL and P25 endogenous proteins by utilizing FibH and FibL promoters; step S2: one of the focused ion beam and the electron beam is selected for exposure to prepare a photoresist pattern. According to the invention, after FibH and FibL promoters are used for specifically regulating FibL and P25 endogenous proteins, the content of the two endogenous silk proteins is reduced, and the mechanical property of silk is greatly improved.

Description

A kind of high tenacity silk full water-based multi-purpose photoresist and preparation method thereof

technical field

The invention belongs to the technical field of bioelectronic information, and in particular relates to a high-toughness silk full water-based multi-purpose photoresist and a preparation method thereof. Photoresist and preparation method thereof.

Background technique

At present, the prosperity of the global semiconductor industry continues to rise. Photolithography process is the core process in semiconductor manufacturing. Photoresist is one of the key materials for micro-pattern processing in microelectronics technology. It is known as the crown of the electronic field and is widely used in the optoelectronic information industry. Especially in recent years, the development of large-scale and ultra-large-scale integrated circuits has greatly promoted the research, development and application of photoresist. At present, in China, there is a "cut-off crisis" in photoresist, and the autonomy of the photoresist industry is imminent. In addition, most commercial photoresists use synthetic polymers or add toxic and harmful organic reagents during production, which violates the development needs of green lithography technology and is not conducive to the sustainable development of national ecology.

SUMMARY OF THE INVENTION

Based on the technical problems existing in the prior art, the present invention provides a high-toughness silk full water-based multi-purpose photoresist and a preparation method thereof.

According to the first aspect of the technical solution of the present invention, a high-toughness silk full water-based multi-purpose photoresist is provided. In order to use the FibH and FibL promoters to specifically regulate the FibL and P25 endogenous proteins to obtain four silkworm strains with excellent silk mechanical properties, after using the FibH and FibL promoters to specifically regulate the FibL and P25 endogenous proteins, the two endogenous silk proteins The content of silk decreased, and the mechanical properties of silk were greatly improved.

According to the second aspect of the technical solution of the present invention, a method for preparing a high-toughness silk full water-based multi-purpose photoresist is provided, which comprises the following steps:

Step S1, utilizes FibH and FibL promoters to specifically regulate and control FibL and P25 endogenous proteins to obtain silk fibroin varieties to extract silk fibroin;

In step S2, one of the focused ion beam or the electron beam is selected for exposure to prepare a photoresist pattern.

Wherein, the step S1 further includes the following step S1-1, degumming: after boiling the 0.5% (M/V) (g/ml) sodium carbonate solution, put the silkworm cocoon shells into the sodium carbonate solution at a liquor ratio of 1:100, Cook for 30min-90min to remove sericin.

Further, step S1 further includes the following step S1-2, after washing the boiled silk in running tap water, soaking it in a cleaning solution, after soaking in the cleaning solution for 30min, changing the cleaning solution once, repeating three times, and then cleaning The resulting silk is dried in a 60° C. oven for 6h-12h for use; the cleaning solution is deionized water.

Further, step S1 further includes the following steps S1-3, wherein anhydrous calcium chloride, anhydrous ethanol, and an aqueous solution are prepared in a molar ratio of 1:2:8 to obtain a silk fibroin solution, and a 1:10 bath is used to prepare a silk fibroin solution. Put a certain amount of silk fibers into the silk fibroin dissolving solution, and dissolve them at a constant temperature between 30°C and 100°C to completely dissolve the silk fibers. At this time, there should be no obvious silk insoluble matter in the dissolving solution; The temperature was 70°C.

In addition, the solubilized silk fibroin solution was placed in a dialysis bag for dialysis for 72h, the retention of the dialysis bag was 8kDa-14kDa, and the water was changed every 3h-5h during the dialysis process.

In addition, the silk fibroin solution is placed in a dialysis bag to be air-dried and concentrated to obtain a certain concentration of silk fibroin aqueous solution, which can be concentrated to 1% to 30% w/w (mass percent g/g) according to subsequent process requirements.

Compared with the prior art, the beneficial effects of a kind of high tenacity silk full water-based multi-purpose photoresist and preparation method thereof of the present invention are:

1. Compared with the traditional photoresist, the high-toughness silk full water-based multipurpose photoresist of the present invention only includes a solvent and a developing solution of water components, and has no other impurities or interference components, which satisfies the current requirements for green lithography technology. development needs.

2. Compared with ordinary silk photoresist, the all-water-based photoresist of high tenacity silk (including the use of FibH and FibL promoters to specifically regulate FibL and P25 endogenous proteins, a total of 4 kinds) has excellent mechanical properties, anti-etching properties. It has a series of outstanding advantages such as good etching performance and high resolution. Its resolution can reach 10nm level, which is more suitable for high-end photoresist applications.

3. The high tenacity silk full water-based multi-purpose photoresist prepared by the present invention can realize "positive and negative dual-use" by changing the degree of silk protein cross-linking. The high-precision bio-micro-nano-fabricated patterns can be prepared in a precise manner, which has excellent application and development prospects.

Description of drawings

Figure 1 is a sample diagram of a high-toughness silk full water-based multi-purpose photoresist sample using the FibH promoter to specifically regulate the FibL silkworm endogenous silk protein.

Figure 2 is a graph showing the molecular size detection result of the high tenacity silkworm silk all-water-based multi-purpose photoresist whose FibH promoter specifically regulates the FibL silkworm endogenous silk protein, which is the SDS-PAGE detection map of the genetically modified silkworm HL silk protein molecule.

Figure 3a and Figure 3b show the exposure results of high-toughness silk full water-based multi-purpose photoresist using the FibH promoter to specifically regulate FibL silkworm endogenous silk protein. Figure 3a is an electron beam positive paste; Figure 3b is an ion beam positive paste.

Figure 4 is a sample diagram of a high-toughness silk all-water-based multi-purpose photoresist.

Fig. 5 is the molecular size detection result of the high-toughness silk full water-based multi-purpose photoresist that utilizes the FibH promoter to specifically regulate the P25 silkworm endogenous silk protein, which is specifically the SDS-PAGE detection map of the HP silk protein molecule of the genetically modified silkworm.

Figures 6a and 6b are the exposure results of high tenacity silk full water-based multi-purpose photoresist using the FibH promoter to specifically overexpress P25 silkworm endogenous silk protein; Figure 6a is an electron beam positive photoresist; Figure 6b is an ion beam positive photoresist .

Figure 7 is a photoresist sample image of using FibL promoter to specifically regulate FibL silkworm endogenous silk protein.

Fig. 8 is a graph showing the result of molecular size detection of FibL silkworm endogenous silk protein photoresist by using FibL promoter to specifically regulate it, and it is a specific SDS-PAGE detection graph of genetically modified silkworm LL silk protein molecule.

Figure 9a and Figure 9b are photoresist exposure results of using FibL promoter to specifically regulate FibL silkworm endogenous silk protein; Figure 9a is an electron beam positive photoresist; Figure 9b is an ion beam negative photoresist.

Figure 10 is a photoresist sample image of using the FibL promoter to specifically regulate the endogenous silk protein of P25 silkworm.

Figure 11 is a graph showing the results of molecular size detection of the endogenous silk protein photoresist of P25 silkworm by using the FibL promoter to specifically regulate it, which is specifically a graph of SDS-PAGE detection of the LP silk protein molecule of genetically modified silkworm.

Figure 12a and Figure 12b are photoresist exposure results of using the FibL promoter to specifically regulate the endogenous silk protein of P25 silkworm, wherein Figure 12a is an electron beam positive glue; Figure 12b is an ion beam negative glue.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the technical solutions, rather than all the embodiments. . Based on the embodiments of the present technical solution, all other embodiments obtained by those of ordinary skill in the art without creative work, all belong to the protection scope of the present invention. In addition, the scope of protection of the present invention should not be limited only to the specific structures or components or specific parameters described below.

The invention provides a high-toughness silk full water-based multi-purpose photoresist and a preparation method thereof. According to the β-sheet structure content of Bombyx mori fibroin and suitable crystallinity, the silk has good mechanical properties, and the polycrystalline The state structure is closely related to the water solubility of silk protein. The invention provides a high-toughness silk full water-based multi-purpose photoresist and a preparation method thereof. Four silkworm strains with excellent silk mechanical properties are obtained by using FibH and FibL promoters to specifically regulate FibL and P25 endogenous proteins respectively. The silk proteins extracted from the four silkworm strains were used as photoresist. The photoresist preparation method of the present invention is simple, environmentally friendly, and low in cost, and can be mass-produced. In addition, the prepared photoresist has excellent mechanical properties and good etching resistance, and can obtain high-precision micro-nano patterns, wherein the resolution can reach 10nm level, which is suitable for the production of finer micro-patterns. The high tenacity silk full water-based multi-purpose photoresist and the preparation method thereof of the present invention comprise using the high tenacity silk obtained by genetically modifying the silkworm endogenous silk protein to prepare the all water-based multi-purpose high-resolution photoresist, and has the advantages of Excellent mechanical properties, anti-etching properties, and can be used as a high-precision biological pattern, low-cost and scalable all-water-based multi-purpose photoresist, the present invention solves commercial photoresist. A series of problems such as high cost and low output.

Further, the present invention relates to a preparation method and application of a genetically modified silk photoresist, wherein the photoresist is a genetically modified endogenous silk fibroin (including using the FibH and FibL promoters to specifically regulate the endogenous FibL and P25 proteins respectively, A total of 4 kinds) obtained the all-water-based silk photoresist prepared from high tenacity silk. The photoresist of the present invention only uses water as a solvent and a developing solution, which meets the current development needs of green lithography technology; The photoresist prepared from silk has a series of outstanding advantages such as excellent mechanical properties, good etching resistance and high resolution, especially the resolution can reach 10nm. Based on the polymorphic structure of silk protein, it can be used as both electron beam photoresist and ion beam photoresist. The preparation of ultra-high-precision biological micro-nano processing patterns has good application prospects.

A high-toughness silk full water-based multi-purpose photoresist of the present invention, the photoresist comprises silk fibroin and an aqueous solution extracted from a silkworm strain, and the silkworm strain uses the FibH and FibL promoters to specifically regulate FibL and P25. Four silkworm strains with excellent mechanical properties of silk obtained from the source protein, after using FibH and FibL promoters to specifically regulate the endogenous proteins of FibL and P25, the content of the two endogenous silk proteins decreased, and the mechanical properties of silk were greatly improved, or even improved. more than double.

Further, by controlling the degree of cross-linking of Bombyx mori fibroin, the "positive and negative dual-use" of the high-toughness silk all-water-based multi-purpose photoresist can be realized. It can be used as a positive photoresist, and the genetically modified Bombyx mori silk photoresist is all water-based, mainly containing three kinds of silk fibroin (FibH, FibL, P25), and does not contain toxic and harmful reagents in commercial photoresists, which meets the requirements to the greatest extent. meet the national strategic needs of green ecology. The high-toughness silk all-water-based multi-purpose photoresist used as a negative adhesive is exposed to water, and the exposed part is insoluble in water, and the illuminated part is left to form a pattern after development; while the high-tenacity silk all-water-based multi-purpose photoresist as a positive photoresist is insoluble in water. The glue needs to be cross-linked, the lighted part is soluble in water, and the unlighted part is left to form a pattern after development. The resolution after exposure can reach 10nm, which is an order of magnitude higher than ordinary silkworm silk. Large-scale fabrication of high-precision biological micro-nano-fabrication patterns.

A method for preparing a high-toughness silk full water-based multi-purpose photoresist of the present invention comprises the following steps:

Step S1, utilizes FibH and FibL promoters to specifically regulate and control FibL and P25 endogenous proteins to obtain silk fibroin varieties to extract silk fibroin;

In step S2, one of the focused ion beam or the electron beam is selected for exposure to prepare a photoresist pattern.

Wherein step S1 further comprises the following steps:

Step S1-1, degumming: after boiling the 0.5% (M/V) (g/ml) sodium carbonate solution, put the cocoon shells into the sodium carbonate solution at a liquor ratio of 1:100, and cook for 30min-90min (minutes) , preferably, cook for 30min to remove sericin;

Step S1-2, after the boiled silk is washed in running tap water, soaked in the cleaning solution, soaked in the cleaning solution for 30 min (minutes), replace the cleaning solution once, repeat three times, and then place the cleaned silk in the cleaning solution. Dry in a 60°C oven for 6h-12h (hours) for later use; the cleaning solution is deionized water;

In step S1-3, anhydrous calcium chloride, anhydrous ethanol, and an aqueous solution are prepared in a molar ratio of 1:2:8 to obtain a silk fibroin dissolving solution, and a certain amount of silk fibers is taken and placed in silk fibroin in a liquor ratio of 1:10. In the protein dissolving solution, under the constant temperature dissolving at any temperature between 30°C and 100°C, the silk fibers are completely dissolved. At this time, there should be no obvious silk insoluble matter in the dissolving solution. The preferred dissolution temperature is 70°C;

Step S1-4, the dissolved silk fibroin solution is placed in the dialysis bag for dialysis 72h, and the interception of the dialysis bag is 8kDa-14kDa, and in the dialysis process, every 3h-5h (hour) changes water once;

Step S1-5, placing the silk fibroin solution in a dialysis bag to air-dry and concentrate to obtain a certain concentration of silk fibroin aqueous solution, which can be concentrated to 1% to 30% w/w (mass percent g/g) according to subsequent process requirements, The preferred concentration is 3% to 7% w/w (mass percentage g/g), after the concentration is completed, an all-water-based photoresist solution of genetically modified silk is obtained, which is stored at low temperature (4° C.). The method for measuring the concentration of silk fibroin solution is as follows: after measuring the weight m ₁ of a petri dish, add 0.5 ml of silk fibroin solution to the petri dish to determine its weight m ₂ , and make it dry at 60°C for 4h- 12h; after the silk fibroin is dried, the weight m ₃ of the culture dish containing the silk fibroin solution is determined, and finally the concentration of the concentrated silk fibroin aqueous solution is calculated by (m ₂ -m ₁ )/(m ₃ -m ₁ ). The molecular weight of silk protein in aqueous solution is about 25kDa or more.

Here, compared with the traditional photoresist, the photoresist of the present invention mainly includes three kinds of silk fibroin (FibH, FibL, P25), and after dialysis, only water is used as a solvent, and there are no other impurities or interfering components to avoid In order to use organic reagents in commercial photoresists, the current development needs of green lithography technology are met. In addition, the method for preparing genetically modified all-water-based photoresist is simple, efficient, and low-cost, which is beneficial to large-scale production and greatly expands the development and utilization of silk.

In addition, compared with ordinary silk photoresists, the all-water-based photoresists based on genetically modified silkworm endogenous silk proteins (including the use of FibH and FibL promoters to specifically regulate FibL and P25 endogenous proteins, a total of 4 kinds) have mechanical properties. It has a series of outstanding advantages such as excellent performance, good etching resistance and high resolution. The resolution can reach up to 10nm, which can meet the processing of higher-precision micro-nano patterns and has important utilization value.

In step S2, the photoresist is obtained by exposure processing by focusing the ion beam/electron beam, which specifically includes the following steps:

In step S2-1, the genetically modified Bombyx mori fibroin aqueous solution obtained in step S1 is spin-coated on the silicon wafer. When the silk protein aqueous solution is spin-coated, the volume of the transgenic Bombyx mori fibroin aqueous solution used is 0.1 mL to 1 mL (milliliter), and the amount of the spin-coating equipment is 0.1 mL to 1 mL. The rotation speed is 1r/min～5000r/min (revolution/min), and the spin coating time is 10s～10min. After spin coating, curing, curing temperature is 30℃～120℃, curing time is 0.3min～50min; preferably curing temperature is 50℃～100℃, curing time is 5min～30min.

In step S2-2, the uniform genetically modified Bombyx mori fibroin film formed by curing is selectively exposed to a focused ion beam or an electron beam. The accelerating voltage of electron beam exposure is 30kV, the dose dose is 0.5-300C cm-2 (coulomb/square centimeter); the accelerating voltage of focused ion beam is 30kV, the beam current is 2pA, and the exposure dose is 0.01s～5s.

In step S2-3, the exposed genetically modified Bombyx mori fibroin film is placed in water for development and drying to obtain a transgenic Bombyx mori fibroin structure; ultrapure water is preferably used for development, and the development time is 1s to 7200s, and the negative glue pattern obtained after development The genetically modified Bombyx mori silk protein can be transformed by radiation based on the secondary conformation, and the exposed part changes from random coil to helical shape, which is not easy to dissolve after developing, and forms a convex structure with better definition.

In order to prepare a positive glue pattern of genetically modified silk protein, the genetically modified silk protein film needs to be cross-linked. The cross-linking method is to soak in methanol reagent for 5 s to 7200 s, so that the secondary conformation of the genetically modified silk protein is changed to β. Folded, the exposed part is transformed into a short polypeptide by radiation, and it is easily dissolved after developing for 1s to 7200s, forming a concave structure with better clarity, and a positive photoresist pattern is obtained. The photoresist prepared by genetically modified silkworm silk has a resolution of up to 11.3 nm.

The technical solutions of the present invention will be further described below with reference to specific embodiments.

Embodiment one, wherein the photoresist obtained is to utilize the FibH promoter to specifically regulate and control the FibL silkworm endogenous silk protein (named HL), by focusing ion beam or electron beam to carry out exposure processing, and the concrete steps are:

1. The silkworm cocoon obtained by utilizing FibH promoter specific regulation and control FibL silkworm endogenous silk protein to obtain is dissolved, and the dissolution method is specifically:

1) Degumming: after boiling the 0.5% (M/V) (g/ml) sodium carbonate solution, put the silkworm cocoon shells into it at a liquor ratio of 1:100 and cook for 30min-90min, preferably for 30min, to remove the sericin. protein;

2) After washing the boiled silk in running water, soak it in deionized water, change the deionized water once after soaking for 30 minutes, repeat three times, and then place the soaked silk in a 60°C oven for 6h to 12h and dry it for later use;

3) Anhydrous calcium chloride, anhydrous ethanol, and an aqueous solution are prepared in a molar ratio of 1:2:8 to obtain a silk fibroin dissolving solution, and a certain amount of silk fibers are taken in a bath ratio of 1:10 and put into the dissolving solution at a constant temperature of 70 ℃. ℃ until completely dissolved, at this time, there should be no obvious silk insoluble matter in the dissolved solution;

4) Place the dissolved silk protein solution in a dialysis bag (the retention capacity of the dialysis bag is 8kDa-14kDa) for 50h～100h, and change the water every 1h～10h during this process; the retention capacity of the dialysis bag is preferably 10kDa～100h. 12kDa, dialysis for 72h, change the water every 3h to 5h;

5) Put the silk fibroin solution in a dialysis bag to air-dry and concentrate, and it can be concentrated to 1% to 30% w/w (mass percent g/g) according to subsequent process requirements, and the preferred concentration is 3% to 7% w/w (mass percent g/g). The method for measuring the concentration of silk protein solution is as follows: after measuring the weight m ₁ of a petri dish, add 0.5 ml of silk protein solution to the petri dish to determine its weight m ₂ , and make it dry at 60°C for 4h-12h; After the silk protein is dried, its weight m ₃ is determined, and finally its concentration is calculated by (m ₂ -m ₁ )/(m ₃ -m ₁ ). Figure 1 is a photoresist sample image of using FibH promoter to specifically regulate FibL silkworm endogenous silk protein, wherein T7 indicates that its concentration is 7% w/w (mass percentage g/g). The photoresist sample is colorless and transparent, mainly containing three kinds of silk fibroin (FibH, FibL and P25), and after dialysis, water is used as a solvent, and it does not contain toxic and harmful organic reagents, which satisfies the biocompatibility of micro-nano processing to the greatest extent. sex and green environmental protection.

6) Fig. 2 is a graph showing the molecular size detection result of using FibH promoter to specifically regulate FibL silkworm endogenous silk protein, and the result shows that the molecular size of the extracted genetically modified silkworm silk protein is mainly more than 25KDa. The specific method of molecular detection was as follows: the photoresist prepared from silk fibroin was diluted 20 times with 8M urea, added with 5×SDS-PAGE Loading Buffer, and after mixing, treated at 98°C for 10min to denature the protein. Use NuPAGE 4-12% Bis-Tris protein gel to separate the denatured protein samples by electrophoresis under the condition of 120V constant pressure. After electrophoresis, use Coomassie brilliant blue staining solution for 10min, and use destaining solution to destain until clear. protein bands.

2. Preparation of micro-nano patterns with excellent mechanical properties, good etching resistance and high precision:

1) Spin-coating the genetically modified Bombyx mori fibroin aqueous solution on a silicon wafer, the volume of the transgenic Bombyx mori fibroin used during spin coating is 0.1 mL-1 mL, the rotational speed is 1000 r/min～5000 r/min, and the spin coating time is 10 s～600 s. Dry and solidify to form a transgenic Bombyx mori silk protein film.

2) Expose the transgenic Bombyx mori fibroin film by electron beam or focused ion beam (one of them is selected at a time). The accelerating voltage of electron beam exposure is 30kV, the dose dose is 0.5-300C cm-2; the accelerating voltage of focusing ion beam is 30kV, the beam current is 2pA, and the exposure time is 0.01s-5s.

3) The exposed genetically modified silk fibroin film sample is placed in water to develop and dry to obtain the genetically modified silk fibroin structure; when the genetically modified silk fibroin is used as a negative glue, the secondary conformation of the exposed part is changed from The random curl becomes an insoluble helical structure. Ultrapure water is used for development. The development time is 1s to 7200s, and a convex negative glue pattern is obtained after development;

When preparing the genetically modified Bombyx mori fibroin positive glue, the genetically modified Bombyx mori fibroin film needs to be cross-linked. The cross-linking method is soaking in methanol reagent for 5s to 7200s, the preferred methanol soaking time is 30min, and the silk protein is soaked in methanol The secondary conformation is converted to β-sheet, and the exposed part is converted into a short polypeptide by radiation, which is easily soluble in water. Ultrapure water is used for development, and after developing for 1s to 2h, a concave positive glue pattern is obtained.

Figure 3 is a photoresist exposure result of using the FibH promoter to specifically regulate the FibL silkworm endogenous silk protein. a: After the silk protein solution is spin-coated and cured by the above method, it is preferably soaked in methanol for 30 minutes, and the secondary conformation of the exposed part is converted from β-sheet to a short polypeptide, and the electron beam positive glue obtained after developing (1s ~ 2h) Exposure diagram; b is after the silk protein solution is spin-coated and cured by the above method, preferably soaked in methanol for 30min, and exposed by ion beam for 2s, the secondary conformation of the exposed part is changed from β-sheet to short polypeptide, after developing ( 1s～2h), the obtained ion beam positive photoresist exposure map has a resolution of 11.3nm (the highest resolution among the four genetically modified silkworm photoresists). Compared with ordinary silk photoresist (30nm), its resolution is improved by more than an order of magnitude, and finer micro-patterns can be produced, which is more in line with the requirements of excellent resolution photoresist.

Embodiment 2, the obtained photoresist is obtained by using the FibH promoter to specifically regulate the P25 silkworm endogenous silk protein (named as HP), and is obtained by exposure processing by electron beam or focused ion beam. Specific steps and examples One is the same. Figure 4 shows the photoresist sample image of using the FibH promoter to specifically regulate the endogenous silk protein of P25 silkworm, wherein T7 indicates that its concentration is 7% w/w (mass percent g/g). Here, compared with the commercial photoresist, the genetically modified silk photoresist is colorless and transparent. Except mainly composed of three kinds of silk fibroin (FibH, FibL, P25), no organic reagents are added. It is based on the biological compatibility and green ecological environmental protection to the greatest extent. Figure 5 shows the result of molecular size detection, and the result shows that the molecular size is about 25KDa or more.

Then spin coating, curing, exposing and developing by the same method in Example 1 to obtain the exposure map of HP photoresist. FIG. 6 is a photoresist exposure result of overexpressing P25 silkworm endogenous silk protein using the FibH promoter. (a is the electron beam positive gel exposure image obtained after the silk protein solution is spin-coated and cured by the above method, preferably immersed in methanol for 30 min; After irradiation, it becomes a soluble short polypeptide, and after developing (1s ~ 2h), a concave pattern is formed. b: After the silk protein solution is spin-coated and cured by the above method, it is preferably immersed in methanol for 30min, and exposed by ion beam for 2s. The same The secondary conformation of silk protein is changed from β-sheet to short polypeptide. The ion beam concave positive photoresist exposure image obtained by developing (1s～2h) has a resolution of 13.1nm, which is higher than the resolution of ordinary silk photoresist. It is more suitable for higher-end applications than ordinary silk photoresist.)

The difference between Example 2 and Example 1 is that the genetic modification is different, and the expression of different endogenous proteins is regulated by the same promoter FibH (Example 1 is the regulation of endogenous protein FibL, and Example 2 is the regulation of endogenous protein P25); Patterns with 10nm-level resolution after exposure with electron beam or focused ion beam are suitable for the production of higher-end photoresists.

In the third embodiment, the obtained photoresist is obtained by using the FibL promoter to specifically regulate and control the FibL silkworm endogenous silk protein (named LL) through exposure processing by electron beam or focused ion beam, and the specific steps are the same as those in the first embodiment. Fig. 7 shows the photoresist sample image of using the FibL promoter to specifically regulate the silkworm endogenous silk protein FibL, wherein T7 indicates that its concentration is 7% w/w (mass percentage g/g). The LL photoresist is colorless and transparent, and its main components are three kinds of silk fibroin (FibL, FibH, P25). Compared with ordinary silk photoresist, because the content of endogenous silk protein is changed, the mechanical properties of silk are improved, and no toxic and harmful reagents are used in the process of extracting silk protein, which is environmentally friendly and suitable for large-scale Production. FIG. 8 shows the result of molecular size detection of LL photoresist, and the result shows that its molecular size is about 25KDa or more.

Figure 9a is the exposure image of the obtained electron beam positive gel after the silk protein solution is spin-coated and cured by the above method, preferably immersed in methanol for 30 min. The secondary conformation of the exposed part is changed from β-sheet to a soluble short polypeptide. Development (1s～2h); b: After the silk protein solution is spin-coated and cured by the above method, it is exposed by ion beam for 1s, and the secondary conformation of the exposed part changes from random coil to insoluble helix. After development (1s～2h) ) exposure map of the resulting ion beam negative gel. Because the content of endogenous silk protein has been changed by genetic modification, the resolution of the photoresist thus prepared reaches 25 nm, which has a great application prospect);

The difference between Example 3 and Example 1 is that the genetic modification is different, and the expression of the same endogenous protein (FibL) is regulated by different promoters (FibH in Example 1 and FibL in Example 3), and the expression of the same endogenous protein (FibL) is regulated by electron beam or focusing. After ion beam exposure, better resolution than ordinary silk can be obtained, which is an order of magnitude higher.

In the fourth embodiment, the obtained photoresist is obtained by using the FibL promoter to specifically regulate the P25 silkworm endogenous silk protein (named LP), and is obtained by exposure processing by electron beam or focused ion beam, and the specific steps are the same as those in the first embodiment. . Figure 10 shows the photoresist sample image of using the FibL promoter to specifically regulate the silkworm endogenous silk protein P25, wherein T7 indicates that its concentration is 7% w/w (mass percent g/g). The LP photoresist is colorless and transparent, and its main components are three kinds of silk fibroin (FibL, FibH, P25). After dialysis, only water is used as a solvent, and no organic reagents are added. Figure 11 is a graph showing the results of the molecular size detection of LP photoresist, and the results show that its molecular weight is about 25KDa or more. Figure 12a shows that after the silk protein solution is spin-coated and cured by the above method, it is preferably soaked in methanol for 30 minutes. After methanol treatment, the secondary conformation of silk protein is β-sheet. After exposure, it becomes a soluble short polypeptide. (1s～2h) The obtained electron beam positive photoresist exposure image; Figure 12b shows that after the silk protein solution was spin-coated and cured by the above method, it was exposed by ion beam for 4s, and the secondary conformation of the exposed part of the silk protein changed from random coil to β-sheet After developing (1s ~ 2h), the exposed part is not easy to dissolve, and the obtained ion beam convex negative photoresist exposure map has a resolution of 15.6nm, which can be widely used in finer micropattern processing. ).

The difference between Example 4 and Example 1 is that the genetic modification is different, and different endogenous proteins (FibL in Example 1 and P25 in Example 4) are regulated by different promoters (FibH in Example 1 and FibL in Example 4). Expression, patterns with 10nm-level resolution can be obtained after exposure with electron beam or focused ion beam.

In summary, the mechanical properties of the genetically modified silkworm silk can be greatly improved (even more than doubled) due to the use of different promoters to change the content of silkworm silk protein. . High efficiency, avoiding the use of a large number of toxic and harmful organic reagents used in commercial photoresists, and low cost, suitable for large-scale production, to the greatest extent to meet the biocompatibility and green ecological sustainability of micro-nano processing. More importantly, compared with ordinary Bombyx mori fibroin photoresist, it has excellent mechanical properties, good etching resistance and high resolution. Among them, the resolution has been improved by more than an order of magnitude. The resolution of genetically modified silk protein photoresist can reach 11.3 nm, which can prepare finer micropatterns, which is suitable for the production of more advanced photoresists and has great application value.

The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this. Substitutions should be covered within the protection scope of the present invention.

Claims (7)

1. a high-toughness silk full-water-based multipurpose photoresist, is characterized in that, the high-toughness silk full-water-based multipurpose photoresist comprises the silk fibroin and the aqueous solution extracted from the silkworm strain, and the silkworm strain is to utilize FibH, Four silkworm strains with excellent silk mechanical properties obtained by the specific regulation of FibL and P25 endogenous proteins by the FibL promoter. After using the FibH and FibL promoters to specifically regulate the endogenous proteins of FibL and P25, the contents of the two endogenous silk proteins decreased, while Its silk mechanical properties are greatly improved. 2. a kind of preparation method of high tenacity silk full water-based multi-purpose photoresist, is characterized in that, it comprises the following steps: Step S1, extracting silk fibroin from a silk fibroin variety obtained by using FibH and FibL promoters to specifically regulate FibL and P25 endogenous proteins; In step S2, one of the focused ion beam or the electron beam is selected for exposure to prepare a photoresist pattern. 3. The method for preparing high-toughness silk full water-based multipurpose photoresist according to claim 2, wherein step S1 further comprises the following steps S1-1, degumming: 0.5% (M/V) (g/ ml) after boiling the sodium carbonate solution, put the cocoon shells into the sodium carbonate solution at a liquor ratio of 1:100, and cook for 30min-90min to remove sericin. 4. The method for preparing high tenacity silk full water-based multi-purpose photoresist according to claim 3, wherein step S1 further comprises the following steps S1-2, after the boiled silk is washed in running tap water, soaked In the cleaning solution, after soaking in the cleaning solution for 30 minutes, the cleaning solution was replaced once and repeated three times, and then the cleaned silk was placed in a 60°C oven for 6h-12h to dry for use; the cleaning solution was deionized water. 5. The method for preparing high-toughness silk full water-based multi-purpose photoresist according to claim 4, wherein step S1 further comprises the following steps S1-3, wherein anhydrous calcium chloride, anhydrous ethanol, an aqueous solution The silk fibroin dissolving solution was prepared at a molar ratio of 1:2:8, and a certain amount of silk fibers were taken into the silk fibroin dissolving solution at a bath ratio of 1:10. Under the constant temperature dissolving, the silk fibers are completely dissolved, and there should be no obvious silk insoluble matter in the dissolving solution at this time; the dissolving temperature is 70°C. 6. high-toughness silk full water-based multi-purpose photoresist preparation method according to claim 5, is characterized in that, the silk fibroin solution that dissolves is placed in dialysis bag for dialysis 72h, and the interception of dialysis bag is 8kDa- 14kDa, the water was changed every 3h-5h during dialysis. 7. The method for preparing high-toughness silk full water-based multi-purpose photoresist according to claim 5, wherein the silk fibroin solution is placed in a dialysis bag for air-drying and concentration to obtain a certain concentration of silk fibroin aqueous solution, according to the The subsequent process requirements can be concentrated to 1% to 30% w/w (mass percentage g/g).

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