Efficient GPP chip glass passivation layer preparation process

Abstract

The invention relates to the technical field of GPP production, in particular to an efficient GPP chip glass passivation layer preparation process. Comprising the steps that a double-groove substrate is manufactured, a PN junction silicon wafer is provided to serve as the substrate, and the silicon wafer comprises double grooves and a metal film table top located on the periphery of the double grooves; glass slurry and a printing film are prepared, the printing film comprises a transparent part of a printing pattern, and the transparent part comprises an area corresponding to the periphery of the metal film table top; registering and coating glass slurry, registering the printing film and the silicon wafer, pouring the glass slurry on the printing film, and uniformly scraping the glass slurry into the groove of the silicon wafer by using a scraper along the diagonal direction of the table surface to obtain the silicon wafer coated with the glass slurry; and drying, curing and sintering, namely drying the silicon wafer coated with the glass slurry in a high-temperature chain furnace, and heating and sintering after drying. According to the invention, a low-cost blade coating method is utilized, and the problems of PN junction sharp corner protection and passivation glass damage caused by cutting are solved.

Description

Technical Field

[0001] The invention relates to the technical field of GPP production, and in particular to an efficient preparation process of a GPP chip glass passivation layer. Background Art

[0002] GPP is the abbreviation of Glassivation, passivation and parts, which is a general term for glass passivation devices. GPP chip glass passivation is a process in which glass slurry is applied to the surface of silicon devices and heated and sintered to form a glass dielectric film. The dielectric film formed by glass passivation can effectively resist the penetration of external impurity gases, the free ion mobility in the film is low, and it has good thermal matching performance and viscosity with silicon. After glass passivation, it is also necessary to make a welding electrode window on the top of the chip. Therefore, it is often hoped that there will be no residual glass on the top of the table after glass passivation or as little residual glass on the top as possible. There are three main processes for preparing the glass passivation layer of existing GPP chips, namely traditional scraping, electrophoresis and photolithography. Regardless of the method, it is necessary to first etch the grooves through photolithography to form grooves and table tops. In the subsequent passivation process, electrophoresis and photolithography consume a lot of glass powder. The production of welding windows is prone to many table top glass points and small effective area, resulting in insufficient height of the solder joint boss, and contact between the metal and the glass passivation layer during welding. In addition, the electrophoresis process is complicated, and the wastewater generated by electrophoresis needs to be treated and discharged. Photolithography is the mainstream of high-end GPP chip preparation because of its good performance. The passivation glass used is a mixture of photoresist and glass powder. Because its passivation glass can cover the sharp corners of the PN junction of the table, and the glass in the groove is removed by photolithography for easy removal. Subsequent cutting, but the photolithography method requires more equipment support, and the cost and requirements for the photolithography machine are relatively high. Therefore, the existing process mostly adopts the scraping method with low process cost. The scraping method is easy to make the welding electrode window, but the scraping method has two main disadvantages. First, the scraping method fills the groove with glass, and it is necessary to etch a laser cutting path on the back. The process is complicated and the back cutting cracks will cause damage to the glass. If the cutting is not done properly, the glass will crack under the action of stress, affecting the reliability of the product. Secondly, in the scraping method, the glass cannot cover the table and cannot protect the sharp corners of the PN junction. The sharp corners are where the electric field is most concentrated, and leakage is prone to occur, causing application failure.

[0003] Therefore, a scraping coating process is needed that can solve the problem of protecting the sharp corners of the PN junction and can be easily cut without damaging the passivation glass. Summary of the invention

[0004] In order to solve the problems of PN junction sharp corner protection and cutting without damaging the passivation glass by using a low-cost scraping method, the present invention provides an efficient GPP chip glass passivation layer preparation process.

[0005] The present invention provides an efficient GPP chip glass passivation layer preparation process, which adopts the following technical solutions: A double-groove substrate is manufactured, and a PN junction silicon wafer is provided as the substrate, wherein the silicon wafer comprises a double groove and a metal film table located around the double groove; Prepare glass paste and printed film, wherein the printed film includes a transparent portion of the printed pattern, and the transparent portion includes an area corresponding to the periphery of the metal film table; Aligning the plate and coating the glass slurry, placing the silicon wafer on the wafer stage by a wafer suction device, aligning the printed film with the silicon wafer, pouring the glass slurry on the printed film, and using a scraper to evenly scrape the glass slurry into the grooves of the silicon wafer along the diagonal direction of the table to obtain a silicon wafer coated with glass slurry; Drying, curing and sintering: the silicon wafer coated with glass slurry is placed in a high-temperature chain furnace for drying, and then heated and sintered.

[0006] Furthermore, the manufacturing of the double-groove substrate includes: Sequentially coating a lower layer of photoresist and an upper layer of photoresist on the etching surface of the silicon wafer, placing a mask in a photolithography machine, and simultaneously exposing the lower layer of photoresist and the upper layer of photoresist by photolithography; Using a positive developer to remove the pattern portion, forming openings of equal width on the lower photoresist and the upper photoresist, curing the upper photoresist, and then using a negative developer to negatively develop the lower photoresist, widening the opening of the lower photoresist in the lateral direction, and using a fixing solution to remove the developer containing photoresist impurities; Forming metal films on silicon wafers using physical sputtering; The developed silicon wafer is etched to form a double groove between two adjacent metal films, and the area covered by the metal film forms a mesa. After etching, the photoresist is removed using a stripping solution.

[0007] Furthermore, the thickness of the upper photoresist layer and the lower photoresist layer is 1-1.5 μm.

[0008] Furthermore, the lower photoresist and the upper photoresist are positive photoresists, the positive developer is n-propanol, the upper photoresist contains a photoinitiator and an epoxy resin, and curing the upper photoresist includes using triethylenetetramine.

[0009] Furthermore, the negative developer contains tetramethylammonium hydroxide, the concentration of tetramethylammonium hydroxide in the negative developer is 2.38-2.42%, and the temperature of the negative development is 23-25°C.

[0010] Furthermore, the etching of the developed silicon wafer includes etching using a wet method, wherein the wet etching includes etching the silicon wafer using a tetramethylammonium hydroxide etching solution, wherein the concentration of tetramethylammonium hydroxide in the etching solution is 20-25%, and the etching temperature is 70-90°C.

[0011] Furthermore, the etching depth is 80-160 μm, the etching width is 200-350 μm, and the line width between the double grooves is 80-130 μm.

[0012] Furthermore, the metal film is made of one of copper, gold, titanium, nickel, silver, platinum and chromium.

[0013] Furthermore, the stripping solution includes one or more of N-methylpyrrolidone, γ-butyrolactone, ethyl lactate and dimethyl sulfoxide.

[0014] Furthermore, the preparation of the glass slurry includes mixing butyl carbitol ethyl acetate and cellulose acetate to form a slurry solvent, and mixing the slurry solvent with glass powder to form the glass slurry.

[0015] Furthermore, the production of the printed film includes selecting a silk screen and coating a photosensitive adhesive on the printing surface of the silk screen, placing the silk screen in a drying oven to dry, closely attaching a patterned film to the silk screen coated with the photosensitive adhesive, exposing, developing and washing the silk screen, wherein the pattern in the patterned film corresponds to the transparent part of the printed pattern.

[0016] Furthermore, the screen is placed in a drying oven for drying at a temperature of 30-40° C. for a drying time of 10-20 minutes, and the developing temperature is 20-30° C. for a time of 1-5 minutes.

[0017] Furthermore, the wire mesh is a polyester wire mesh of 300-500 meshes.

[0018] Furthermore, the aligning of the printed film and the silicon wafer includes adjusting the position of the silicon wafer to be 0.5 mm to 1 mm below the printed film.

[0019] Furthermore, the scraper evenly scrapes the glass slurry into the grooves of the silicon wafer along the diagonal direction of the table, including applying downward pressure to the printed film, the pressure value is not more than 80N, the speed of the scraper is not more than 300mm / s, the angle between the scraper and the plane of the printed film is 40-90 degrees, and the number of unidirectional scraping by the scraper is not more than 5 times.

[0020] Furthermore, the drying temperature of the drying and curing is 150-200° C., the drying time is 60-90 seconds, the sintering temperature is 650-850° C., the sintering time is 6-7 hours, and 99.99% oxygen is passed through the sintering process.

[0021] In summary, the present invention has the following beneficial technical effects: 1. The present invention proposes an efficient GPP chip glass passivation layer preparation process, the product has PN junction sharp corner protection, the glass slurry is coated around the metal film by printing the film, the PN junction sharp corner is effectively protected, the leakage caused by the electric field concentration at the PN junction sharp corner is reduced, and the electrical performance and service life of the chip are improved.

[0022] 2. The present invention proposes an efficient GPP chip glass passivation layer preparation process, which is easy to cut and the passivation glass is damageless. By etching double grooves, there is no need to perform complex back etching laser cutting procedures in the subsequent cutting process, thereby avoiding damage to the glass caused by back cutting cracks in traditional processes and the problem of hidden cracks in the glass, and reducing the cost increase caused by cutting damage.

[0023] 3. The present invention saves process steps and reduces costs. The present invention eliminates the expensive back-side photolithography plate. Since there is no need to perform back-side photolithography operation, the corresponding process flow is simplified. Compared with the photolithography method, the equipment required is simpler and no high-precision photolithography machine is required. When making the table, the etching of double grooves is completed at the same time. The produced printed film can be reused, and the production efficiency and stability are good.

[0024] 4. The table of the present invention has no glass spots, and it is easy to weld the leads. The preparation of the metal electrode is completed before etching the double grooves. The metal film is made by two layers of photoresist and using the front and back steps of positive developer and negative developer. At the same time, the etching solution is used to etch the silicon wafer without damaging the metal film. The double grooves are etched, wherein the generation of the metal film not only saves the production of the table electrode in the subsequent process but also protects the silicon wafer electrode, thereby producing a special structure of the double grooves, and using the alignment and coating of the printed film to completely expose the metal film table without glass spots. Compared with the electrophoresis method, the environmental protection advantage is outstanding, and the equipment requirements are greatly reduced compared with the photolithography method. The present invention has high production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flow chart of an efficient process for preparing a glass passivation layer of a GPP chip according to Example 1 of the present invention.

[0026] Figure 2 This is a flow chart of manufacturing a double-groove substrate according to Example 1 of the present invention.

[0027] Figure 3 It is a schematic diagram of the structure of the device prepared by the scraping method in the prior art of Example 1 of the present invention.

[0028] Figure 4 It is a schematic diagram of the structure of a device prepared by photolithography in the prior art of Example 1 of the present invention.

[0029] Figure 5 It is a schematic diagram of the structure of a silicon wafer coated with photoresist according to Example 1 of the present invention.

[0030] Figure 6 It is a schematic diagram of the structure of the silicon wafer after photolithography according to Example 1 of the present invention.

[0031] Figure 7 It is a schematic diagram of the structure of the cured upper photoresist according to Example 1 of the present invention.

[0032] Figure 8 It is a schematic structural diagram of the opening of the lower layer photoresist being widened laterally according to Embodiment 1 of the present invention.

[0033] Fig. 9 It is a schematic diagram of the structure of the sputtered metal film of Example 1 of the present invention.

[0034] Fig.10 It is a schematic diagram of the structure of etching double trenches in Example 1 of the present invention.

[0035] Fig.11 It is a schematic structural diagram of stripping photoresist according to Example 1 of the present invention.

[0036] Fig.12 Schematic diagram of the coating glass paste of Example 1 of the present invention.

[0037] Fig.13 It is a schematic diagram of the structure of the device after sintering of Example 1 of the present invention.

[0038] Among them, 1. Silicon wafer; 2. Metal film; 3. Table; 4. Glass slurry; 5. Lower photoresist layer; 6. Upper photoresist layer; 7. Cured layer; 8. Double grooves; 9. Printed film; 10. Scraper; 11. Sharp corners. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0040] Example 1 In the prior art, reference Figure 3 In the prior art, the GPP chip prepared by the scraping method has continuous glass between the table tops 3 and the table tops 3, and a laser cutting path needs to be etched on the back. The process is complicated and the glass will be damaged when the back is cut. If the cutting is improper, the glass will crack under the stress, affecting the reliability of the product. Secondly, in the scraping method, the glass cannot cover the table top 3 and cannot protect the sharp corner 11 of the PN junction. The sharp corner 11 is where the electric field is most concentrated, and leakage is prone to occur, resulting in application failure.

[0041] Reference Figure 4In the prior art, the GPP chip prepared by photolithography is used. The glass in the groove is removed by photolithography to facilitate subsequent cutting, and the sharp corner 11 of the PN junction is protected. It is applied to scenes with high equipment requirements. However, the glass paste 4 of the photolithography method is mixed with photoresist to form photoresist glass, which requires a photolithography machine to etch the cutting channel. At the same time, the exposed table 3 needs to be etched above the table 3. When making the welding window, it is easy to have many glass points on the table 3 and a small effective area, resulting in insufficient height of the solder joint boss, and contact between the metal and the glass passivation layer during welding. At the same time, it has high requirements for the photolithography equipment. It is necessary to etch the groove first, then etch the glass paste, prepare the cutting channel and remove the glass paste on the table. Two photolithography processes are required. The second photolithography has high requirements for photolithography accuracy, and the process is complicated and the preparation cost is high.

[0042] Reference Figure 1 , an efficient GPP chip glass passivation layer preparation process of this embodiment includes: S1. Prepare a double trench 8 substrate, provide a PN junction silicon wafer 1 as a substrate, and the silicon wafer 1 includes a double trench 8 and a metal film 2 mesa 3 located around the double trench 8.

[0043] Reference Figure 2 The manufacturing of the double groove 8 substrate comprises: Reference Figure 5 , S11. The lower photoresist 5 and the upper photoresist 6 are sequentially coated on the etching surface of the silicon wafer 1, the mask is placed in a photolithography machine, and the lower photoresist 5 and the upper photoresist 6 are simultaneously exposed by photolithography, wherein the thickness of the upper photoresist 6 and the lower photoresist 5 is 1-1.5 μm.

[0044] It is a prior art to make a silicon wafer 1 with a PN junction. Donor impurities (such as phosphorus) are doped on one side of the silicon wafer 1 by diffusion or ion implantation to form an N-type region; acceptor impurities (such as boron) are doped on the other side to form a P-type region. The doped silicon wafer 1 is subjected to appropriate heat treatment to promote the diffusion and activation of impurities to form a stable PN junction. Before coating the lower layer of photoresist 5, the etched surface of the silicon wafer 1 is ensured to be clean, and the organic matter and oxide layer on the surface are removed by RCA cleaning method. When coating the photoresist, the coating thickness is ensured to be uniform by adjusting the speed of the coating machine. The present invention uses a silicon wafer with a PN junction for preparation, and the PN layer is not shown in the figure.

[0045] Reference Figure 6 and Figure 7 , S12. Using a positive developer to remove the pattern portion, respectively, on the lower photoresist 5 and the upper photoresist 6 to form openings of equal width, the upper photoresist 6 is cured to form a cured layer 7, reference Figure 8, and then negatively develop the lower photoresist 5 using a negative developer to widen the opening of the lower photoresist 5 in the lateral direction, and use a fixing solution to remove the developer containing impurities in the photoresist.

[0046] Among them, the lower photoresist 5 and the upper photoresist 6 are positive photoresists, the positive developer is n-propanol, the upper photoresist 6 contains a photoinitiator and an epoxy resin, and the curing of the upper photoresist 6 includes using triethylenetetramine, and the curing temperature is 150-170°C. The epoxy resin in the upper photoresist 6 can react with triethylenetetramine to form a cured layer 7.

[0047] The negative developer solution contains tetramethylammonium hydroxide, the concentration of tetramethylammonium hydroxide in the negative developer solution is 2.38-2.42%, and the negative development temperature is 23-25° C. The negative development time is controlled within 60-120 seconds, and the fixing time is controlled within 30-60 seconds.

[0048] Reference Fig. 9 , S13. Form a metal film 2 on the silicon wafer 1 by physical sputtering, wherein the metal film 2 is made of one of copper, gold, titanium, nickel, silver, platinum and chromium.

[0049] Physical sputtering requires the use of physical sputtering equipment. The sputtering gas (usually argon) is ionized under the action of a high electric field to form a plasma. The ions in the plasma bombard the target material, causing the target material atoms to be sputtered out and deposited on the surface of the silicon wafer 1 to form a metal film 2. At the same time, the metal film 2 is also sputtered on the upper photoresist 6. The metal film 2 of the upper photoresist 6 is removed along with the removal of the photoresist in the subsequent process.

[0050] Reference Fig.10 S14. The developed silicon wafer 1 is etched to form a double groove 8 between two adjacent metal films 2, and the area covered by the metal film 2 forms a mesa 3. After etching, the photoresist is removed using a stripping solution.

[0051] The etching of the developed silicon wafer 1 includes wet etching, wherein the wet etching includes etching the silicon wafer 1 with a tetramethylammonium hydroxide etching solution, wherein the concentration of the tetramethylammonium hydroxide in the etching solution is 20-25%, and the etching temperature is 70-90°C.

[0052] Tetramethylammonium hydroxide does not react with the metal film 2 and has no dissolving effect. The metal film 2 plays a role in protecting the silicon in the covering area from being etched.

[0053] The etching depth is 80-160 μm, the etching width is 200-350 μm, and the line width between the double grooves 8 is 80-130 μm.

[0054] Reference Fig.11The stripping solution includes one or more of N-methylpyrrolidone, γ-butyrolactone or ethyl lactate and dimethyl sulfoxide.

[0055] After etching, the solution containing the stripping solution is evenly sprayed or immersed on the silicon wafer 1 to make the stripping solution fully contact with the photoresist. After the photoresist is dissolved, the silicon wafer 1 is rinsed with deionized water to remove the residual stripping solution and photoresist impurities.

[0056] S2. Prepare a glass paste 4 and a printed film 9, wherein the printed film 9 includes a transparent portion of the printed pattern, wherein the transparent portion includes an area corresponding to the surroundings of the metal film 2 table 3; S21. Preparing glass slurry 4, comprising mixing butyl carbitol ethyl acetate and cellulose acetate to form a slurry solvent, and mixing the slurry solvent with glass powder to form glass slurry 4.

[0057] Butyl carbitol ethyl acetate and cellulose acetate are mixed as slurry solvents to provide a uniform medium environment. The mixing ratio of butyl carbitol ethyl acetate and cellulose acetate is 2:3, so that the glass powder can be fully dispersed and form a stable slurry system. Butyl carbitol ethyl acetate has good solubility and volatility, and can gradually evaporate in the subsequent drying and curing process, while cellulose acetate can increase the viscosity and stability of the slurry and prevent the glass powder from precipitating and agglomerating during the mixing process.

[0058] The mass ratio of glass powder to slurry solvent is between 1:1.5 and 1:2. During the stirring process, care should be taken to prevent the glass powder from agglomerating, and the stirring speed should be increased for 60-90 minutes until the glass powder is evenly dispersed in the slurry solvent to form a stable glass slurry 4.

[0059] S22. Making a printed film 9, including selecting a silk screen and coating a photosensitive adhesive on the printing surface of the silk screen, the coating thickness is controlled at 5-10 μm, after the coating is completed, the silk screen is placed in a drying oven to dry, the patterned film is tightly attached to the silk screen coated with the photosensitive adhesive, and the silk screen is exposed, developed and washed, wherein the pattern in the patterned film corresponds to the transparent part of the printed pattern.

[0060] S23. Place the screen in a drying oven to dry at a temperature of 30-40°C for 10-20 minutes, and the developing temperature is 20-30°C for 1-5 minutes. The screen is a 300-500 mesh polyester screen. The polyester screen has good strength and wear resistance, and can withstand multiple printing and scraping operations without being easily damaged.

[0061] Reference Fig.12, S3. Aligning and coating the glass paste 4, placing the silicon wafer 1 on the wafer stage by the suction device, aligning the printed film 9 with the silicon wafer 1, pouring the glass paste 4 on the printed film 9, and using a scraper 10 to evenly scrape the glass paste 4 into the groove of the silicon wafer 1 along the diagonal direction of the table 3 to obtain the silicon wafer 1 coated with the glass paste 4; The printing film 9 and the silicon wafer 1 are aligned, including adjusting the position of the silicon wafer 1 to 0.5mm-1mm below the printing film 9. When applying the glass paste 4, a proper distance is maintained between the printing film 9 and the silicon wafer 1 to facilitate the flow and filling of the glass paste 4, and at the same time, the glass paste 4 is better covered around the table 3 to protect the sharp corners 11 of the table 3.

[0062] The scraper 10 is made of stainless steel or polytetrafluoroethylene. The scraper 10 evenly scrapes the glass slurry 4 into the groove of the silicon wafer 1 along the diagonal direction of the table 3, including applying downward pressure to the printed film 9, the pressure value is not more than 80N, the speed of the scraper 10 is not more than 300mm / s, the angle between the scraper 10 and the plane of the printed film 9 is 40-90 degrees, and the number of unidirectional scraping of the scraper 10 is not more than 5 times.

[0063] A small amount of glass paste 4 will remain on the silicon wafer between the double grooves, and the main body of the passivation glass will not be damaged during cutting.

[0064] Reference Fig.13 S4. Drying, curing and sintering: the silicon wafer 1 coated with the glass slurry 4 is placed in a high-temperature chain furnace for drying, and then heated and sintered.

[0065] The drying temperature of the drying and curing is 150-200°C, the drying time is 60-90s, the sintering temperature is 650-850°C, the sintering time is 6-7h, and 99.99% oxygen is passed during the sintering process. After sintering is completed, the high-temperature chain furnace is closed, and the silicon wafer 1 is taken out after being cooled naturally in the furnace.

[0066] Finally, the silicon wafer 1 is laser cut by a laser cutting device, and the cutting is performed along the unetched pillars between the double grooves 8 without manual splitting. The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An efficient GPP chip glass passivation layer preparation process, characterized in that: include: A double-groove substrate is manufactured, and a PN junction silicon wafer is provided as the substrate, wherein the silicon wafer comprises a double groove and a metal film table located around the double groove; Prepare glass paste and printed film, wherein the printed film includes a transparent portion of the printed pattern, and the transparent portion includes an area corresponding to the periphery of the metal film table; Aligning the plate and coating the glass slurry, placing the silicon wafer on the wafer stage by a wafer suction device, aligning the printed film with the silicon wafer, pouring the glass slurry on the printed film, and using a scraper to evenly scrape the glass slurry into the grooves of the silicon wafer along the diagonal direction of the table to obtain a silicon wafer coated with glass slurry; Drying, curing and sintering: the silicon wafer coated with glass slurry is placed in a high-temperature chain furnace for drying, and then heated and sintered.

2. The efficient GPP chip glass passivation layer preparation process according to claim 1, characterized in that: The manufacturing of the double groove substrate comprises: Sequentially coating a lower layer of photoresist and an upper layer of photoresist on the etching surface of the silicon wafer, placing a mask in a photolithography machine, and simultaneously exposing the lower layer of photoresist and the upper layer of photoresist by photolithography; Using a positive developer to remove the pattern portion, forming openings of equal width on the lower photoresist and the upper photoresist, curing the upper photoresist, and then using a negative developer to negatively develop the lower photoresist, widening the opening of the lower photoresist in the lateral direction, and using a fixing solution to remove the developer containing photoresist impurities; Forming metal films on silicon wafers using physical sputtering; The developed silicon wafer is etched to form a double groove between two adjacent metal films, and the area covered by the metal film forms a mesa. After etching, the photoresist is removed using a stripping solution.

3. The efficient GPP chip glass passivation layer preparation process according to claim 2, characterized in that: The thickness of the upper photoresist layer and the lower photoresist layer is 1-1.5 μm.

4. The efficient GPP chip glass passivation layer preparation process according to claim 2, characterized in that: The lower photoresist and the upper photoresist are positive photoresists, the positive developer is n-propanol, the upper photoresist contains a photoinitiator and an epoxy resin, and curing the upper photoresist includes using triethylenetetramine.

5. The efficient GPP chip glass passivation layer preparation process according to claim 2, characterized in that: The negative developer solution contains tetramethylammonium hydroxide, the concentration of tetramethylammonium hydroxide in the negative developer solution is 2.38-2.42%, and the temperature of the negative development is 23-25°C.

6. The efficient GPP chip glass passivation layer preparation process according to claim 2, characterized in that: The etching of the developed silicon wafer includes etching by wet method, wherein the wet etching includes etching the silicon wafer by using tetramethylammonium hydroxide etching solution, wherein the concentration of tetramethylammonium hydroxide in the etching solution is 20-25%, and the etching temperature is 70-90°C.

7. The efficient GPP chip glass passivation layer preparation process according to claim 2, characterized in that: The etching depth is 80-160 μm, the etching width is 200-350 μm, and the line width between the double grooves is 80-130 μm.

8. The efficient GPP chip glass passivation layer preparation process according to claim 2, characterized in that: The metal film is one of copper, gold, titanium, nickel, silver, platinum and chromium.

9. The efficient GPP chip glass passivation layer preparation process according to claim 1, characterized in that: The method of making the printed film comprises selecting a silk screen and coating a photosensitive adhesive on the printing surface of the silk screen, placing the silk screen in a drying oven for drying, closely attaching a patterned film to the silk screen coated with the photosensitive adhesive, and exposing, developing and washing the silk screen, wherein the pattern in the patterned film corresponds to the transparent part of the printed pattern.

10. The efficient GPP chip glass passivation layer preparation process according to claim 1, characterized in that: The step of aligning the printed film with the silicon wafer includes adjusting the position of the silicon wafer to be 0.5 mm to 1 mm below the printed film.

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