CN113548803A - Passivation protection semiconductor glass powder, preparation method and application - Google Patents
Passivation protection semiconductor glass powder, preparation method and application Download PDFInfo
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- CN113548803A CN113548803A CN202110823152.1A CN202110823152A CN113548803A CN 113548803 A CN113548803 A CN 113548803A CN 202110823152 A CN202110823152 A CN 202110823152A CN 113548803 A CN113548803 A CN 113548803A
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- glass powder
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C12/00—Powdered glass; Bead compositions
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C3/00—Glass compositions
- C03C3/04—Glass compositions containing silica
- C03C3/062—Glass compositions containing silica with less than 40% silica by weight
- C03C3/064—Glass compositions containing silica with less than 40% silica by weight containing boron
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C8/00—Enamels; Glazes; Fusion seal compositions being frit compositions having non-frit additions
- C03C8/24—Fusion seal compositions being frit compositions having non-frit additions, i.e. for use as seals between dissimilar materials, e.g. glass and metal; Glass solders
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/28—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection
- H01L23/29—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the material, e.g. carbon
- H01L23/291—Oxides or nitrides or carbides, e.g. ceramics, glass
Abstract
The invention develops a preparation method of passivation protection semiconductor glass powder, and the glass powder can be used for preventing semiconductor oxidation, preventing acid, alkali and light from corroding semiconductor and the like. The lead-free low-melting-point glass powder prepared by the invention can be synthesized by a sol-gel method, and is calcined in an air atmosphere to form a glassy compact layer with strong adhesion property. The glass transition temperature of the glass frit can be further improved by introducing an auxiliary agent during the sol-gel process. The invention synthesizes R-Al by adopting a sol-gel method2O3‑B2O3‑SiO2‑Bi2O3The glass powder provides a new idea for passivation protection of semiconductor materials.
Description
Technical Field
The invention relates to a glass powder which is developed and designed for protecting a semiconductor material which is easily corroded by acid, alkali and other substances or easily oxidized.
Background field of the invention
Semiconductor material applications are very widespread, ranging from electron tubes to transistors to large scale and very large scale integrated circuits, which contain large amounts of semiconductor material. The semiconductor exists in the aspects of our lives, and provides great help for our lives. However, with the rapid development of electronic technology, the requirements for electrical characteristics, reliability, miniaturization and the like of semiconductors are higher and higher, and the exposed surface of the semiconductor is actually the edge from which the semiconductor lattice is arranged to the termination, and unsaturated bonds exist on the termination edge, so that the surface state of the semiconductor is easy to change, and the electrical performance of the device is poor; some semiconductors are exposed in the air and are easily corroded by substances such as acid, alkali, light and the like, so that the performance of the semiconductors is weakened or even disappears, and passivation protection treatment needs to be carried out on the surfaces of the semiconductors.
In the middle of sixties, the American general electric company adopts multicomponent oxide glass for the first time, is used for passivating the diode and also serves as an appearance packaging material, and greatly improves the performance of the diode. From the seventies, competitive research in the countries of the United states, the Japan, the Germany and the like continuously expands the application range of the glass passivation technology in high-voltage-resistant, high-temperature-resistant and high-power semiconductor devices. The research of glass powder for semiconductor chips in China begins in the eighties, the glass powder starts late, the quality of the developed glass powder is different from the advanced level in the world, and the glass powder and the auxiliary agent required by the production and the manufacture of the semiconductor chips depend on the import from abroad to a great extent, so that the research of the high-quality low-melting-point glass powder is urgent.
Among them, the glass passivation (GP for short) technique of passivating semiconductor p-n junction with fused glass has been widely used in the production of semiconductor materials. The glass powder of the basic material of GP technique has excellent electrical insulation property and chemical stability, and has certain mechanical strength after sintering, so that the glass powder with proper melting point and expansion coefficient is selected to prepare a layer of glass film on the surface of the semiconductor p-n junction, thereby playing good passivation and protection roles on the semiconductor chip p-n junction.
The development of the glass powder with low glass transition temperature capable of forming an effective protective layer can improve the manufacturing level of semiconductor materials in China, promote the development and progress of the semiconductor industry in China and improve the competitiveness of China in the semiconductor material market; can overcome the import requirement of a large number of semiconductors and realize the independent intellectual property rights and the localization of the semiconductor glass powder. Therefore, the development of glass frits for passivation protection of semiconductors and other materials is not trivial.
As is well known, the traditional glass powder is prepared by a melting-quenching method, melting and quenching are needed at high temperature (more than 1000 ℃), and grinding is carried out by a planetary ball mill, so that the energy consumption is high and certain potential safety hazards exist. The glass powder has a high glass transition temperature and poor adhesion to a semiconductor, and thus cannot protect the semiconductor. More importantly, how to realize lower glass transition temperature in the preparation process of the glass powder has important significance for effectively protecting the semiconductor p-n junction. The glass transition temperature of the glass powder can be reduced and the adhesive capacity of the glassy state compact layer can be improved by adjusting the type and the content of the auxiliary agent.
Disclosure of Invention
Aiming at the problems in the prior art, the invention prepares the lead-free glass powder with strong adhesive property by using a sol-gel method for passivating and protecting the semiconductor material.
The glass powder is R-Al2O3-B2O3-SiO2-Bi2O3(R is an oxide of a second main group metal), and the raw materials comprise the following components in percentage by mass: bi2O3：49％-52％、SiO2：27％-33％、B2O3：27％-33％、Al2O3: 4% -8%, R: 1-4% (R is an oxide of a metal of the second main group).
The components in the glass powder of the invention have mutual synergistic effect, wherein Bi2O3、SiO2、B2O3The glass is a main component of glass, has the advantages of high adhesion performance, low expansion coefficient, electrical insulation performance, chemical stability and the like, and can reduce the glass transition temperature of glass powder, further increase the adhesion capability of the glass and improve the mechanical performance of the glass when R is added into a glass system as an auxiliary agent, wherein the addition amount of R is not more than 8%.
The invention provides a simple sol-gel preparation method, which comprises the following steps:
1) dissolving tetraethyl orthosilicate (TEOS) in a solution of ethanol and deionized water, stirring for 30-60min at 50-80 ℃, wherein the volume ratio of TEOS to the ethanol solution is controlled to be 0.25-0.5, and then adding nitric acid, and controlling the pH of the solution to be 1-3;
2) adding boric acid with a certain mass into the mixture obtained in the step 1), and continuously hydrolyzing for 15-30 min;
3) adding a certain mass of R (second main group metal) salt raw material and aluminum salt raw material into the mixture obtained in step 2) and continuing hydrolysis for 0-5 min;
4) adding a bismuth salt raw material with a certain mass into the mixture obtained in step 3), adjusting the pH value of the mixture to be less than 2 by using nitric acid, adding a complexing agent with the same molar mass, and continuously stirring to form transparent gel;
5) drying the obtained transparent gel at 30-60 ℃ for 10-24h, and drying in an oven at 150-200 ℃ for 10h to obtain xerogel;
6) and (3) preserving the obtained dried gel in a muffle furnace in a protective atmosphere for 30-60min, setting the temperature at 350-500 ℃, and grinding the calcined dried gel to obtain the glass powder.
The raw material of the R salt is one or more than two of nitric acid R, acetic acid R, chloridized R, acetic acid R and sulfuric acid R.
The aluminum salt raw material is one or two of aluminum nitrate, aluminum sulfate and aluminum chloride.
The bismuth salt raw material is one or two of bismuth nitrate, bismuth sulfate and bismuth chloride.
The complexing agent is one or two of citric acid, polyacrylic acid and polyacrylamide.
The protective atmosphere is one or two of nitrogen, argon and air.
The invention has the advantages that:
the method for preparing the glass powder has low energy consumption, easily obtained raw materials and high economical efficiency; the prepared glass powder has the advantages of high adhesion, low expansion coefficient, electric insulation performance, chemical stability, low glass transition temperature, strong mechanical property and the like, and is used for passivating and protecting semiconductor materials.
Drawings
FIGS. 1 to 4 show R-Al prepared according to the present invention2O3-B2O3-SiO2-Bi2O3And (5) glass powder pictures.
FIGS. 5 to 8 show the R-Al obtained after calcination according to the present invention2O3-B2O3-SiO2-Bi2O3And (4) glass pictures.
FIG. 9 shows MgO-Al prepared by the present invention2O3-B2O3-SiO2-Bi2O3XRD pattern of glass powder
Detailed Description
Example 1
Table one composition of the glass frit is as follows:
| composition of | Bi2O3 | SiO2 | B2O3 | Al2O3 | MgO |
| Mass content | 49％ | 20％ | 20％ | 8％ | 4％ |
Weighing salt raw materials corresponding to the oxides according to the table I, preparing glass powder according to the steps, wherein the color of the obtained glass powder is yellow brown, grinding the glass powder subjected to heat treatment into fine powder in a grinding bowl, weighing a certain amount of glass powder, putting the glass powder in a quartz boat, heating the quartz boat to 800 ℃ in a muffle furnace at the temperature rise rate of 5 ℃/min, and naturally cooling the quartz boat to room temperature in the muffle furnace.
The glass powder for passivating and protecting the semiconductor, which is researched and developed by the invention, is environment-friendly, is non-toxic and harmless, can be formed into glass by calcining at 800 ℃, has stronger adhesive force, low expansion coefficient, electrical insulation performance, chemical stability and mechanical performance, can prevent corrosion of acid, alkali and light and the like, and is widely applied to passivating and protecting semiconductor materials.
Example 2
The compositions of the glass powder of the second table are as follows:
| composition of | Bi2O3 | SiO2 | B2O3 | Al2O3 | CaO |
| Mass content | 49％ | 20％ | 20％ | 8％ | 4％ |
And weighing salt raw materials corresponding to the oxides according to the second table, preparing glass powder according to the steps, wherein the color of the obtained glass powder is grey brown, grinding the glass powder subjected to heat treatment into fine powder in a grinding bowl, weighing a certain mass of the glass powder, putting the glass powder in a quartz boat, heating the quartz boat to 800 ℃ in a muffle furnace at the temperature rise rate of 6 ℃/min, and naturally cooling the quartz boat to room temperature in the muffle furnace.
The glass powder for passivating and protecting the semiconductor, which is researched and developed by the invention, is environment-friendly, is non-toxic and harmless, can be formed into glass by calcining at 800 ℃, has stronger adhesive force, low expansion coefficient, electrical insulation performance, chemical stability and mechanical performance, can prevent corrosion of acid, alkali and light and the like, and is widely applied to passivating and protecting semiconductor materials.
Example 3
The compositions of the glass powder of the third table are as follows:
| composition of | Bi2O3 | SiO2 | B2O3 | Al2O3 | BaO |
| Mass content | 49％ | 20％ | 20％ | 8％ | 4％ |
Weighing salt raw materials corresponding to the oxides according to the third table, preparing glass powder according to the steps, grinding the glass powder after heat treatment into fine powder in a grinding bowl, weighing the glass powder with a certain mass, placing the glass powder in a quartz boat, heating the quartz boat to 800 ℃ in a muffle furnace at the heating rate of 6 ℃/min, and naturally cooling the quartz boat to room temperature.
The glass powder for passivating and protecting the semiconductor, which is researched and developed by the invention, is environment-friendly, is non-toxic and harmless, can be formed into glass by calcining at 800 ℃, has stronger adhesive capacity, low expansion coefficient, electrical insulation performance, chemical stability and mechanical performance, can prevent corrosion of acid, alkali and light and the like, and is widely applied to passivating and protecting semiconductor materials.
Example 4:
table four the compositions of the glass frits are as follows:
| composition of | Bi2O3 | SiO2 | B2O3 | Al2O3 | SrO |
| Mass content | 49％ | 20％ | 20％ | 8％ | 4％ |
Weighing salt raw materials corresponding to the oxides according to the fourth table, preparing glass powder according to the steps, grinding the glass powder after heat treatment in a grinding bowl into fine powder, weighing a certain mass of the glass powder, putting the glass powder in a quartz boat, heating the quartz boat to 800 ℃ in a muffle furnace at the temperature rise rate of 6 ℃/min, and naturally cooling the quartz boat to room temperature.
The glass powder for passivating and protecting the semiconductor, which is researched and developed by the invention, is environment-friendly, is non-toxic and harmless, can be formed into glass by calcining at 800 ℃, has stronger adhesive capacity, low expansion coefficient, electrical insulation performance, chemical stability and mechanical performance, can prevent corrosion of acid, alkali and light and the like, and is widely applied to passivating and protecting semiconductor materials.
In summary, the present invention is described in the embodiments, but the scope of the present invention is not limited thereto, and any person skilled in the art should also cover the technical scope of the present invention, the technical solutions and the inventive concepts of the present invention with equivalent substitutions or changes.
Claims (9)
1. A preparation method of passivation protection semiconductor glass powder comprises the following steps:
1) dissolving tetraethyl orthosilicate in an ethanol aqueous solution, stirring at 50-80 ℃ for 30-60min, wherein the volume ratio of the tetraethyl orthosilicate to the ethanol aqueous solution is 0.25-0.5, and then adding nitric acid to control the pH of the solution to be 1-3;
2) adding boric acid into 1), and continuing to hydrolyze for 15-30 min;
3) adding the R salt raw material and the aluminum salt raw material into the mixture obtained in the step 2) and continuing to hydrolyze for 0-5 min;
4) adding a bismuth salt raw material into the mixture obtained in the step 3), adjusting the pH value of the mixture to be less than 2 by using nitric acid, adding a complexing agent with the same molar mass, and continuously stirring to form transparent gel;
5) drying the obtained transparent gel at 30-60 ℃ for 10-24h, and drying in an oven at 150-200 ℃ for 10h to obtain xerogel;
6) and (3) preserving the obtained dried gel in a muffle furnace in a protective atmosphere for 30-60min, setting the temperature at 350-500 ℃, and grinding the calcined dried gel to obtain the glass powder.
2. The method for preparing passivation semiconductor glass powder according to claim 1, wherein the method comprises the following steps: the salt R is one or more than two of nitric acid R, oxalic acid R, chloridized R, acetic acid R and sulfuric acid R.
3. The method for preparing passivation semiconductor glass powder according to claim 1, wherein the method comprises the following steps: the aluminum salt raw material is one or two of aluminum nitrate, aluminum sulfate and aluminum chloride.
4. The method for preparing passivation semiconductor glass powder according to claim 1, wherein the method comprises the following steps: the bismuth salt raw material is one or two of bismuth nitrate, bismuth sulfate and bismuth chloride.
5. The method for preparing passivation semiconductor glass powder according to claim 1, wherein the method comprises the following steps: the complexing agent is one or two of citric acid, polyacrylic acid and polyacrylamide.
6. The method for preparing passivation semiconductor glass powder according to claim 1, wherein the method comprises the following steps: the protective atmosphere is one or two of nitrogen, argon and air.
7. The method for preparing passivation semiconductor glass powder according to claim 1, wherein the method comprises the following steps: the weight ratio of tetraethyl orthosilicate, boric acid, aluminum salt raw material, R salt raw material and bismuth salt raw material is as follows: 27-33: 27-33: 4-8: 1-4: 49-52.
8. A glass frit for passivation protection of semiconductors, characterized in that the glass frit is prepared by the preparation method according to any one of claims 1 to 7.
9. Use of the glass frit for passivation of semiconductor protection according to claim 8 for passivation and protection of p-n junctions of semiconductors.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114195395A (en) * | 2021-12-08 | 2022-03-18 | 安徽大学 | Low-melting-point lead-free glass powder for passivating and protecting semiconductor and preparation method thereof |
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2021
- 2021-07-20 CN CN202110823152.1A patent/CN113548803A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPH08310836A (en) * | 1995-05-11 | 1996-11-26 | Sumitomo Osaka Cement Co Ltd | Spherical glass powder and its production |
| CN101891390A (en) * | 2009-12-31 | 2010-11-24 | 四川虹欧显示器件有限公司 | Lead-free medium slurry and manufacturing method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114195395A (en) * | 2021-12-08 | 2022-03-18 | 安徽大学 | Low-melting-point lead-free glass powder for passivating and protecting semiconductor and preparation method thereof |
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