JPH01502631A - Electrical insulation method for large area electrode body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Electrical insulation method for large area electrode body 1 step 1 The present invention provides a method for facilitating the next step in manufacturing semiconductor devices, particularly solar cells. The present invention relates to a method of electrically insulating a large-area electrode body.

11 stories The manufacturing process of electronic devices requires many complex steps and precise handling. series In the manufacturing process of devices connected to It is necessary to separate the underlying components of the device. Manufacture of such devices In this case, the electrical isolation process can be difficult and complicated.

Layers are used to electrically isolate various layers of adjacent cells or building blocks in a device. It is well known in the prior art to irradiate a laser beam across the surface of a semiconductor substrate. Mechanical separation also directs the abrasive flow towards abrasive tools and microelectronic devices. In recent years, polishing trimmers and the like with nozzles have been used. A club between semiconductor comrades Removal of the material layer in minutes until the electrical resistance of the electrode in that part rises to the desired value , by removing the cross-sectional portion located between the semiconductors.

In traditional methods, a patterned material layer is deposited using a mechanical mask on the substrate during deposition. It was formed by holding and vapor depositing. Unfortunately, mechanical masking It is appropriate to say that it has the effect of blocking a significant portion of The area under the mask required to achieve the desired separation is too large to fabricate semiconductor devices. This is because it is too loud. In addition to this, the problem occurs due to the difficulty in positioning the mask. There are also problems.

U.S. Patent No. 3,691,695, granted to Green et al. on September 19, 1972. The issue describes a microelectronic device with a nozzle that sprays abrasive material directly onto microelectronic elements. A polishing trimmer for devices is disclosed. The nozzle is mounted on a pivot shaft and is set to its initial normal operating position in the retracted state. electrical circuits are trimmed It senses the electrical properties of microelectronic devices that are It will send a signal when it is detected.

No. 8,444,3651 issued to Swartz on April 17, 1984. discloses amorphous silicon solar cells formed in series on a single substrate. There is. Forming such series-connected amorphous silicon solar cells inexpensively The method used a series of paints sprayed through a grooved mask. 0, which involves a “paint and peel” method, where the paint is removed and the resulting metal parts forms a protrusion that extends to the electrode above it.

U.S. Patent No. 4,590,093, issued to Walley et al. on May 20, 1986. A method for forming thin conductors made of metal silicide is disclosed in this issue. Open As shown, the patterned polycrystalline silicon covers a large portion of the protective layer. By covering the edges with metal, the edges are converted to metal silicide. It will be done. The remaining silicon portion is selectively removed, and the traces formed serve as a conductor mask. I can work there.

Therefore, one object of the present invention is to provide electrical isolation for large-area electrode bodies for semiconductor device manufacturing. Another purpose of the present invention is to perform edge cutting without expensive laser scribing methods. or mechanical scribing methods that consume valuable board area for insulation. The purpose of this method is to separate electrode bodies of semiconductor devices such as solar cells without having to use a solar cell.

I Mamedate! j The present invention provides an improved method for electrically insulating large area electrode bodies. Sara For details, refer to 5. The present invention is applied to the manufacturing process of semiconductor devices, in which fine particles of thin film electrode bodies are It provides a chemical method for separation. Decide on the masking agent in advance. A pattern is provided on the surface of the substrate. Preferred masking agents are organic solvents A masking agent such as a solvent selected from the group consisting of The resulting material is one that can be easily removed with a chemically inert solvent.

Examples of organic solvents include alcohol, acetone, etc. Examples of aqueous solutions include acidic solutions. can be mentioned.

A conductive electrode material is then formed over the patterned masking agent, and By dissolving in a solvent, the masking agent interacts with the electrode material formed on it. Also removed. After removal, at least a portion of the substrate is exposed and electrically isolated. electrically insulated from each other to provide the desired electrical connection between the electrode parts. Ru.

Masking agents include polymeric materials, carbonaceous materials, sulfates, nitrates, photoresists, and acids. Selected from the group consisting of salts and salts. The masking agent is preferably a carbonated bag. calcium carbonate, or silicon carbide. The process of applying masking agent is It is performed by one step of clean printing or photolithography.

Another preferred masking agent, particularly suitable for screen printing, is Examples include pastes, which are mixtures of powder, vehicle, and other materials.

Calcium carbonate, barium carbonate, or silicon carbide is preferred as the shielding powder. , these materials are deposited on top of the masking agent by chemical vapor deposition to form an upper layer. It is stable even at high temperatures, usually around 400 to 600℃, and does not damage the substrate or mass. This is because it is substantially chemically inert to the upper layer film formed on the king agent.

Furthermore, regarding calcium carbonate, powder with uniform particle size can be easily obtained. It is evenly dispersed in the vehicle and provides a uniform shielding effect. Moreover, calcium carbonate is very easily removable by acidic solutions.

The average particle size of the shielding powder is desirably less than 0.51 Lm, more preferably It is preferable that the maximum particle size is less than 0.51Lm.The smaller the particle size, the more The shielding effect of the skinning agent is improved. Also, the smaller the particle size, the better the masking agent. This makes it possible to screen print finer patterns. In other words, the thickness is smaller. This allows you to print in narrower widths. This is especially important for photovoltaic switching cells. It is. This is because if the masking agent used during screen printing is too thick, it will not coat the surface. This causes very high protrusions to occur at the edges of each part of the layered film, and this This can be fatal as the protrusion contacts the back electrode of the photoelectric exchange cell and causes a short circuit. This becomes a problem. Also, if the width of the screen-printed masking agent is wide, the photovoltaic The surface area of the solar-exposed active part of the conversion cell is reduced, reducing the photoelectric conversion efficiency. This is because you end up doing it.

However, on the other hand, if the particle size of the shielding powder is too small, it will not distribute uniformly into the vehicle. It is difficult to disperse, and moreover, it is difficult to make very fine particles. For these reasons, the average particle size of the shielding powder is less than 0.5 μm and more than osgm. It is preferable that

The vehicle contained in the masking agent has excellent screen printing properties and can be printed in fine patterns. If it has a viscosity that allows printing with good dimensional accuracy and can be easily removed, it is fine. Considering these properties, the vehicle is ethylcellulose, nitrocellulose, Preferably, those containing a base or acrylic resin are used to adjust the viscosity. Solvents that are compatible with the substances may be added, if necessary, high boiling point solvents, oxidation Agents etc. may be added to the vehicle.

The masking agent contains 40 to 60 wt% of the above-mentioned shielding powder and 60 to 40 wt% of the vehicle. It is preferable that it contains t%.

The pattern in which the masking agent disclosed in the present invention is provided is suitable for semiconductor devices. A rectangular shape that extends from one end of the base to the other. It contains a pattern that leaves a conductive band. Such conductive bands are arranged between each conductive band. To minimize the distance, for example, keep the distance between about 0-1 mm or more and about 1.0 mm or less. According to the method of the present invention, not only such patterns but also any type of pattern can be formed. Patterns of various shapes are also possible.

The formation of the upper layer film consisting of conductive electrode material is carried out using tin oxide containing indium and fluorine doped. from transparent conductive oxides such as doped tin oxide and antimony-doped tin oxide. In order to remove the masking agent and the electrode material formed thereon, the substrate is Sonically and/or chemically cleaned.

The masking agent is thereby removed, and as a result, the substrate is partially exposed and the above electrode is removed. The portion of the material that remains on the substrate is electrically insulated. This allows isolated electrical Pole bodies are formed and selective electrical connections are made between such electrically isolated electrode portions. It becomes possible. There is an electrical resistance of 1000Ω or more between such electrically insulated electrode parts. exhibits electrical resistance that causes separation.

The advantage of the present invention is that it is inexpensive and accurate, without the use of lasers or mechanical polishing equipment. Other advantages and features of the present invention include the ability to remove electrode materials. That's recognized.

just snow Figures 1a to 1C used the method of the invention. Manufacture of semiconductor devices such as solar cells FIG. 2 is a cross-sectional view showing an outline of the manufacturing process.

FIG. 2 is a plan view showing an example of a substrate patterned according to the present invention.

−／Bear The method of the present invention is illustrated in FIG. FIG. 1a also shows a substrate 14 and a preselected pattern. A device designated 10 is shown having a masking agent 12 provided with There is. Typical examples of the base 14 include glass, but plastic, metal foil, etc. , silicon wafers, gallium arsenide univar, conventionally used substrates, etc.

The substrate 14 may be made of a material other than glass, but may be a non-conductive, insulating substrate such as glass. In the case of a glass substrate containing an alkali metal, the substrate 14 may contain such an alkali metal. S,02. A sentence consisting of 0, ZrO2, etc. The size of the substrate, which may include a lukewarm anti-diffusion layer, is 1 foot x 1 It can be of any size, including substrates for foot solar cells.

The materials constituting the masking agent 12 include polymer materials, carbonaceous materials, sulfates, and nitrates. , photoresists, oxides, carbides, carbonates. Good and preferred masking agents include barium carbonate, calcium carbonate, or charcoal. Examples include silicon oxide. Other preferred masking agents include shielding powders, vehicle and mixtures of other materials. Pre-selected masking agent 12 The resulting pattern is formed by screen printing or a single photolithography process. The constituent material of the masking agent 12 is preferably made of an organic solvent and an aqueous solution. It is selected in consideration of ease of removal by a solvent selected from the group consisting of:

Of course, various solvents must be selected and used depending on the type of masking agent. No.

When using a masking agent containing a shielding powder and a vehicle, Before forming a layer film, the masking agent needs to be dried or pre-baked.

In FIG. 2, the masking agents 12 extend from one end of the substrate 14 to the other at intervals. An example is shown in which they are provided in a pattern that forms a rectangular strip 20.

The masking agent is provided to minimize the spacing 21 between each strip. this is , it is more advantageous to maximize the surface area of the sun-exposed active part of the photovoltaic material. This is particularly advantageous in the field of photoelectric conversion elements, which have many advantages. The minimum between the strips 20 The interval 21 is preferably about 0.1 mm or more and about 1.0 mm or less.

Next, as shown in Figure 1b, indium oxide containing tin.

Made of transparent conductive oxide electrode materials such as tin oxide doped with fluorine or antimony. Jjli 16 applies the shape from above the masking agent 12 applied in a pattern. will be accomplished. The upper layer M16 has a diameter of 300A or more and 20,000A or less, preferably 3 It is formed with a thickness of 000A or more and 20000A or less.

Device 10 is then contacted with a solvent to remove masking agent 12. Ma The skinning agent 12 is applied to ultrasonic cleaning and/or chemical cleaning 1 such as spray pass, tap removed in organic or aqueous solutions by water baths or other conventional cleaning methods. .

Then, as shown in Figure IC, the masking agent 12 is removed and a pattern is placed on the substrate 14. The etched electrode material N16 is left behind. After removing the masking agent 12, The resistance will be 1000Ω or more. As a result, the electrode material 16 is divided into separate electrode parts. A structure like the one shown in FIG. 1c is created when separated. Now these electrode parts are integrated. Series connection can be made in the next manufacturing process of overlapping photoelectric conversion devices.

The protrusion 17 on the edge of the electrode portion 16 is coated with a very thin layer of masking agent. This can be reduced if printing is performed. This means that the particle size is small, preferably less than 0.5 lm This can be achieved by using a masking agent having a shielding powder of

The invention will be explained in more detail by the following examples.

1st Seal” A rectangular shape extending from one end of the base to the other on a 1 foot sized glass substrate. With a pattern like the one shown in Figure 2 that covers the strip, the width of the strip is about 1 cm. m, and the spacing between the strips was approximately 0.5 mm, and the barium carbonate was placed in a desired mask. A pattern of the dyeing agent was formed. After that, a transparent conductive oxide film with a pattern is applied. Next, apply barium carbonate and alcohol. It was removed by chemical cleaning inside. Part of the glass substrate is exposed and transparent conductive oxide The remaining portion was electrically isolated with a resistance of 5000Ω or more.

The Emperor of China” (average particle size) (100 g of calcium carbonate powder of approximately 0.3 μm and ethyl cellulose) 6 wt% and trimethylpentanediol monoisobutyrate) 94 wt% Knead with 90g of vehicle, and then add trimethylpentanediol monoisobutylene. ) to form a paste-like mass with a viscosity of 5ooooocps at 25°C. A king agent was prepared.

1 foot large, with one layer of alkali diffusion barrier made of SiO2 on the surface. on a soda lime silicate glass substrate with a rectangular shape extending from one end of the substrate to the other. Adjust the width of the strip with a pre-selected pattern that leaves a strip of shape. The above masking agent was applied on top with a width of about 1 cm and a spacing between the strips of about 0.4 mm. Screen printed on the 5i02 calendar. Automatically placed by screen printing process The desired masking agent pattern was formed. The thickness of the printed masking agent is approximately 1 It was 0Bm.

The glass substrate with the pattern-printed masking agent was heated at 150°C for 10 minutes. After drying, put it into the CVD equipment.

It was heated to 500°C. Tetramethyltin vapor oxygen (0.517 min), and bromoto Nitrogen gas containing refluoromethane (CFB, 0.11/ml) was A 1.0 wt% film was sprayed onto the glass substrate with the above pattern printed at 217 m1n. An upper layer m (II thickness: 5000 A) made of fluorine-doped tin oxide was formed.

Next, the masking agent was removed by ultrasonic cleaning in an aqueous solution. Part of the glass substrate The remaining portions of the exposed, fluorine-doped tin oxide film are connected to each other by a resistance of 4000Ω or more. electrically isolated with resistance. Edges of each part of fluorine-doped tin oxide film The height of the edge protrusion was approximately 0.21 Lm.

Next, a plasma CVD method was applied to the glass substrate having the patterned tin oxide film. An amorphous silicon film (M thickness 400OA) was formed using A silver film was formed on the amorphous silicon film to produce a solar cell.

Each section corresponding to each patterned portion of the tin oxide film of the solar cell When we examined the electrical characteristics of each section, there were no sections where a short circuit occurred.

In the above examples and explanations, specific examples of transparent conductive oxides and masking agents were illustrated, but It should be noted to those involved in such technology that other materials not exemplified can also be used. is clear. Furthermore, the above description and examples are directed to electrode body materials. However, the usefulness of the present invention is not limited to this. It attempts to specify the scope of the invention.

FJGLJF? E I a FIGυREIb FIGURE Ic FIGURE 2 −　International search report

Claims (27)

[Claims] 1. A preselected pattern is placed on a substrate that has a surface that supports the masking agent. applying a masking agent with a mask; On the masking agent provided with the pattern, indium oxide containing tin, film A group consisting of fluorine-doped tin oxide and antimony-doped tin oxide forming an upper layer film made of a transparent conductive oxide electrode material selected from; By dissolving the masking agent and the electrode material formed on it in a solvent, removing the electrode material, thereby exposing at least a portion of the substrate; The remaining parts of the substrate form the desired electrical connection between the electrically isolated electrode parts. a step of electrically insulating each other so that connections can be made; and a large surface for facilitating series connection of semiconductors formed on the electrode body. A method of electrically insulating a stacked electrode body. 2. The substance subsequently formed and the substantially chemically inactive solvent Applying an easily removable masking agent onto a substrate having a surface forming the masking agent. process of providing a pattern with a preselected pattern; A process of forming an upper layer film made of a conductive oxide electrode material on the masking agent that has been exposed. Process: Dissolving the masking agent and the electrode material formed thereon in the above solvent. and removing at least a portion of the substrate, thereby exposing at least a portion of the substrate; The portion of the electrode material remaining on the substrate is placed between the electrically isolated electrode portions as desired. making them electrically isolated from each other so that electrical connections can be made; and a large surface for facilitating series connection of semiconductors formed on the electrode body. A method of electrically insulating a stacked electrode body. 3. The process of providing a masking agent involves the use of polymeric materials, carbonaceous materials, sulfates, nitrates, A mass selected from the group consisting of photoresists, oxides, carbides, carbonates Claim 1 or 2, characterized in that it is achieved by providing a king agent. Electrical insulation method for large area electrode bodies. 4. The masking agent is a glue made of barium carbonate, calcium carbonate, and silicon carbide. 4. The large area electrode body according to claim 3, wherein the electrode body is selected from the group consisting of: Gas insulation method. 5. The step of providing a masking agent includes forming a masking agent consisting of a shielding powder and a vehicle. A large area according to claim 1 or 2, characterized in that the large area is achieved by providing an agent. Method of electrically insulating electrode bodies. 6. The shielding powder is a group consisting of barium carbonate, calcium carbonate, and silicon carbide. The electrical conductivity of the large area electrode body according to claim 5, characterized in that it is selected from Insulation method. 7. Claim 5, characterized in that the shielding powder has a particle size of less than 0.5 μm. A method for electrically insulating large-area electrode bodies. 8. The vehicle is made of ethylcellulose, nitrocellulose, and acrylic resin. Claim 5, characterized in that it contains at least one species selected from the group consisting of: A method for electrically insulating large-area electrode bodies. 9. The process of providing masking agents involves applying masking agents that extend from one end of the substrate to the other at intervals. This is done by providing a pattern that applies to series connections, including rectangular strips. 3. The method of electrically insulating a large-area electrode body according to claim 1 or 2. 10. Claim 9, characterized in that the strips are formed with a minimum distance from each other. A method for electrically insulating the large-area electrode body described above. 11. Characterized by the minimum interval between the strips being 0.1 mm or more and 1.0 mm or less The method of electrically insulating a large-area electrode body according to claim 10. 12. The process of applying the masking agent on the substrate involves applying the masking agent to a non-conductive insulator. The main body according to claim 1 or 2, characterized in that it is achieved by providing on a base body. Method of electrically insulating area electrode bodies. 13. The process of providing a masking agent consists of a group consisting of an organic solvent and an aqueous solution. This is accomplished by providing a masking agent that is easily removed by the chosen solvent. 3. The method of electrically insulating a large-area electrode body according to claim 1 or 2. 14. 14. The large area electrode according to claim 13, wherein the organic solvent is alcohol. Method of electrically insulating pole bodies. 15. The large-area electrode body according to claim 13, wherein the aqueous solution is an acidic solution. electrical isolation method. 16. Formation of the upper layer film consisting of a conductive oxide electrode material involves forming a transparent conductive oxide. The electrical conductivity of the large area electrode body according to claim 2, characterized in that the electrical Insulation method. 17. The formation of the upper layer film consisting of a conductive oxide electrode material consists of indium oxide containing tin. 3. The large-area electrode body according to claim 2, wherein the large-area electrode body is formed by forming a electrical isolation method. 18. The formation of the upper layer film consisting of a conductive oxide electrode material consists of fluorine and antimony. Claim 2, characterized in that it is achieved by forming doped tin oxide. A method for electrically insulating large-area electrode bodies. 19. Formation of the upper layer of conductive oxide electrode material involves depositing such material at a thickness of 3000 Å. It is characterized by being formed by forming a film with a thickness of at least 20,000 Å or less. A method for electrically insulating a large-area electrode body according to claim 1 or 2. 20. The masking agent is removed by ultrasonic cleaning. A method for electrically insulating a large-area electrode body according to claim 1 or 2. 21. The masking agent is removed by chemical cleaning. A method for electrically insulating a large-area electrode body according to claim 1 or 2. 22. It is noted that the process of applying the masking agent is carried out by screen printing. 3. The method of electrically insulating a large-area electrode body according to claim 1 or 2. 23. The process of applying the masking agent is a process using photolithography. The electrical isolation of the large area electrode body according to claim 1 or 2, characterized in that Edge method. 24. By removing the masking agent, electrical isolation of 1000Ω or more can be achieved. 3. The method of electrically insulating a large area electrode body according to claim 1 or 2, characterized in that: Law. 25. On a glass substrate having a surface, a distance of about 0.1 mm or more and 1.0 mm or less from each other is formed. Pre-selected to leave rectangular strips extending from edge to edge of the substrate at intervals. Step of applying barium carbonate with the selected pattern; A step of forming an upper layer film made of a transparent conductive oxide on the oxidized barium carbonate; By dissolving barium carbonate and the electrode material formed on it in alcohol. The glass substrate is thus removed, thereby exposing at least a portion of the glass substrate and making it transparent. The remaining portions of the conductive oxide are electrically insulated between the transparent conductive oxide portions. providing electrical isolation so that the desired electrical connections can be made; and a large surface for facilitating series connection of semiconductors formed on the electrode body. A method of electrically insulating a stacked electrode body. 26. On a glass substrate having a surface, a distance of about 0.1 mm or more and 1.0 mm or less from each other is formed. Pre-selected to leave rectangular strips extending from edge to edge of the substrate at intervals. from calcium carbonate, barium carbonate, and silicon carbide with selected patterns. A maskin comprising at least one powder selected from the group consisting of a vehicle and a vehicle. applying the adhesive by screen printing; A coating made of a transparent conductive oxide is placed on the masking agent provided with the pattern. Step of forming a layer; the masking agent and the electrode material formed thereon are dissolved in an aqueous solution. removing at least a portion of the glass substrate by dissolving it in the glass substrate, thereby removing at least a portion of the glass substrate; The remaining portion of the transparent conductive oxide is exposed and the remaining portion of the transparent conductive oxide is electrically insulated. electrically isolated to allow the desired electrical connection between the oxidized portions. The process of making; and a large surface for facilitating series connection of semiconductors formed on the electrode body. A method of electrically insulating a stacked electrode body. 27. Characterized by the fact that the masking agent is removed by ultrasonic cleaning in an aqueous solution. 27. The method of electrically insulating a large-area electrode body according to claim 26.