Method for preparing micropore micro-valve silicone rubber chip from negative photosensitive adhesive

Abstract

The invention discloses a method for preparing a micropore micro-valve silicone rubber chip from negative photosensitive glue. The method comprises the following steps: S1, coating a silicon wafer with PCB photosensitive blue oil by using a nylon wire net; s2, the silicon wafer coated with the blue oil is placed in a drying oven to be dried, and after drying is completed, the silicon wafer is cooled to the room temperature; s3, a film (negative film) printed with a chip microchannel is attached to the surface of the blue oil coating, four corners of the silicon wafer are attached and fixed through transparent adhesive tape, exposure is carried out through ultraviolet rays, then the film is stripped, the silicon wafer is soaked in a developing solution, after soaking and developing, the unexposed part is cleaned up through a brush, and washing is carried out through running water. According to the manufacturing method, the microporous micro-valve silicone rubber chip is manufactured by combining a screen cloth difference secondary photosensitive blue oil coating method with a twice exposure mode, so that line width change and technical difficulty caused by long-time exposure of positive optical cement are avoided, multiple times of exposure are not needed, the process is simpler, the chip manufacturing flow is shortened, and the production cost is reduced. And the preparation of the chip is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of microvalve silicone rubber chip preparation, and in particular to a method for preparing a microporous microvalve silicone rubber chip by preparing negative photosensitive adhesive. Background Art

[0002] The microporous microvalve chip uses microvalves to precisely control the flow of microfluids in the chip. The microcylinder lever connects the pipes below the cylinder with pipes in different directions in the substrate to complete the opening and closing of the flow path. It is a special chip.

[0003] Positive photoresist is usually used for the positive mold of the integrated PDMS chip of the micropore microvalve silicone rubber chip, but it has obvious disadvantages. The pipeline is thin (0.5mm) and the channel is shallow (0.1-0.2mm). At the same time, long-term exposure will bring about changes in line width and technical difficulties. If diluted positive photoresist is used for multiple exposure superposition (through multiple coating / exposure, 4-5 times), theoretically a millimeter-level convex positive mold with a semicircular cross-section can be achieved, but the process is complicated. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings existing in the prior art, such as: the pipeline is thin, the channel is shallow, and long-term exposure will bring about changes in line width and technical difficulties; if multiple exposures are superimposed with diluted positive photoresist, theoretically a millimeter-level convex positive mold with a semicircular cross-section can be achieved, but the process is complicated, and a method for preparing a negative photosensitive resin to prepare a microporous microvalve silicone rubber chip is proposed.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing a microporous microvalve silicone rubber chip by using a negative photosensitive adhesive comprises the following steps:

[0007] S1, use nylon mesh to apply PCB photosensitive blue oil on the silicon wafer;

[0008] S2, placing the silicon wafer coated with blue oil in an oven to dry, and after drying, cooling to room temperature;

[0009] S3, a film (negative film) printed with chip microchannels is pasted on the surface of the blue oil coating, the four corners of the silicon wafer are fixed with transparent tape, and exposed to ultraviolet light, then the film is peeled off, and the silicon wafer is soaked in developer. After soaking and developing, the unexposed part is cleaned with a brush and rinsed with running water;

[0010] S4, taking out the rinsed silicon wafer and drying it in an oven;

[0011] S5. Take another piece of nylon screen, lay it flat on a smooth plastic plate, take a small amount of photosensitive blue oil, scrape it over the entire screen (screen polyurethane scraper), keep the photosensitive blue oil moist, slowly lift the screen film with tweezers, and transfer it to the upper surface of the silicon wafer;

[0012] S6, peeling off the silk screen film from the surface of the silicon wafer, and turning the silicon wafer upside down so that its upper surface faces downward in an inverted state, and placing the silicon wafer on the frame with the middle empty;

[0013] S7, then transfer the silicon wafer to an oven for drying. After drying, take out the blue oil silicon wafer, place the original film close to the blue oil coating surface, and expose it again;

[0014] S8, peeling off the film on the silicon wafer, and soaking the silicon wafer in a developer, using a brush to remove the unexposed part after soaking, washing with running water, blowing away excess water with a hair dryer, and then drying in an oven, thereby obtaining the preparation of a positive mold of a chip integrated with a microchannel and microvalve;

[0015] S9. Use the chip positive mold as a mold and cast silicone rubber AB glue to obtain a silicone rubber pipeline part chip (upper part). Then use air plasma to treat the silicone rubber surface and bond it with another thin film silicone rubber to obtain a microporous microvalve silicone rubber chip.

[0016] Preferably, the silicon wafer is a single-side polished silicon wafer, and the photosensitive blue oil in S1 is applied to the polished side of the silicon wafer.

[0017] Preferably, after the S3 running water rinse, solidified blue oil raised lines appear on the silicon wafer, and the cross-section of the lines is rectangular.

[0018] Preferably, when the silk screen film is transferred to the upper surface of the silicon wafer with the convex lines, the silk screen film is brought into contact with the convex lines on the surface of the silicon wafer.

[0019] Preferably, when the silk screen film is peeled off from the surface of the silicon wafer, the photosensitive blue oil adhering to the raised lines on the silicon wafer is in a semi-fluid state.

[0020] Preferably, after placing the silicon wafer on the frame in S6, the silicon wafer needs to be left to stand for more than 10 minutes.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: the micropore microvalve silicone rubber chip is manufactured by a method of differential secondary photosensitive blue oil coating on a silk screen cloth in combination with a double exposure method, thereby avoiding line width changes and technical difficulties caused by long-term exposure using positive photoresist, and no multiple exposures are required. The process is simpler, the chip manufacturing process is shortened, the chip production time is reduced, and it is beneficial to chip preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention provides a flow chart of a method for preparing a microporous microvalve silicone rubber chip using a negative photosensitive adhesive. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0024] Reference Figure 1 A method for preparing a microporous microvalve silicone rubber chip using a negative photosensitive adhesive comprises the following steps:

[0025] S1, use nylon mesh to apply PCB photosensitive blue oil on the silicon wafer;

[0026] S2, placing the silicon wafer coated with blue oil in an oven to dry, and after drying, cooling to room temperature;

[0027] S3, a film (negative film) printed with chip microchannels is pasted on the surface of the blue oil coating, the four corners of the silicon wafer are fixed with transparent tape, and exposed to ultraviolet light, then the film is peeled off, and the silicon wafer is soaked in developer. After soaking and developing, the unexposed part is cleaned with a brush and rinsed with running water;

[0028] S4, taking out the rinsed silicon wafer and drying it in an oven;

[0029] S5. Take another piece of nylon screen, lay it flat on a smooth plastic plate, take a small amount of photosensitive blue oil, scrape it over the entire screen (screen polyurethane scraper), keep the photosensitive blue oil moist, slowly lift the screen film with tweezers, and transfer it to the upper surface of the silicon wafer;

[0030] S6, peeling off the silk screen film from the surface of the silicon wafer, and turning the silicon wafer upside down so that its upper surface faces downward in an inverted state, and placing the silicon wafer on the frame with the middle empty;

[0031] S7, then transfer the silicon wafer to an oven for drying. After drying, take out the blue oil silicon wafer, place the original film close to the blue oil coating surface, and expose it again;

[0032] S8, peeling off the film on the silicon wafer, and soaking the silicon wafer in a developer, using a brush to remove the unexposed part after soaking, washing with running water, blowing away excess water with a hair dryer, and then drying in an oven, thereby obtaining the preparation of a positive mold of a chip integrated with a microchannel and microvalve;

[0033] S9, using the chip positive mold as a mold, casting and re-molding with silicone rubber AB glue, thereby obtaining a silicone rubber pipeline part chip (upper part), and then using air plasma to treat the silicone rubber surface and bond it with another thin film silicone rubber to obtain a microporous microvalve silicone rubber chip;

[0034] The silicon wafer is a single-sided polished silicon wafer, and the photosensitive blue oil in S1 is applied to the polished side of the silicon wafer; after being rinsed with running water in S3, a solidified blue oil raised line appears on the silicon wafer, and the cross section of the line is rectangular; when the silk screen film is transferred to the upper surface of the silicon wafer with the raised lines, the silk screen film is made to fit and contact with the raised lines on the surface of the silicon wafer, so as to facilitate the application of photosensitive blue oil on the raised lines on the surface of the silicon wafer;

[0035] When the silk screen film is peeled off from the surface of the silicon wafer, the photosensitive blue oil adhering to the raised lines on the silicon wafer is in a semi-fluid state, and the photosensitive blue oil can flow and deform at this time; after placing the silicon wafer on the frame in S6, the silicon wafer needs to be left to stand for more than 10 minutes to allow the semi-fluid photosensitive blue oil to form a semicircle under the suspension effect of gravity.

[0036] In the present invention, when the device is used, PCB photosensitive blue oil is firstly coated on a single-side polished silicon wafer with a nylon screen, and then the silicon wafer coated with blue oil is placed in an oven for drying. After the silicon wafer is dried, the silicon wafer is cooled to room temperature, and then a film printed with a chip microchannel is pasted on the surface of the blue oil coating, and the four corners of the silicon wafer are pasted and fixed with transparent adhesive. After the fixing is completed, the silicon wafer is exposed with an ultraviolet lamp. After the exposure is completed, the film is peeled off from the surface of the silicon wafer, and the silicon wafer is sent to a developer for immersion and development. After the development of the silicon wafer is completed, the silicon wafer is taken out, and the unexposed part of the silicon wafer surface is cleaned with a brush. After the cleaning is completed, After the formation, the silicon wafer is rinsed with running water. At this time, the silicon wafer shows raised lines of solidified blue oil, and the cross-section of the lines is rectangular. Then the silicon wafer is dried in an oven. At the same time, another nylon screen is taken and laid flat on a flat and smooth plastic plate. A small amount of photosensitive blue oil is taken and scraped to fill the entire screen. The photosensitive blue oil is kept moist, and the screens are filled with a sufficient amount of photosensitive blue oil. The screen film is slowly lifted with tweezers and transferred to the upper surface of the silicon wafer with the raised lines, so that the screen film is in contact with the raised lines on the surface of the silicon wafer, and then the screen film is peeled off from the surface of the silicon wafer. At this time, the photosensitive blue oil adhering to the raised lines on the surface of the silicon wafer is The photosensitive blue oil is in a semi-fluid state, and then the silicon wafer is turned upside down with the upper surface of the silicon wafer facing down in an inverted state. At the same time, the silicon wafer is placed on a frame with an empty space in the middle and left to stand for more than 10 minutes to allow the semi-fluid photosensitive blue oil to flow and deform. The semi-fluid photosensitive blue oil forms a semicircle under the hanging effect of gravity, and then the silicon wafer in this state is transferred to an oven for drying. Next, the dried blue oil silicon wafer is taken out, and the original film is closely aligned with the surface of the blue oil coating, and it is exposed again by ultraviolet light. After the exposure is completed, the film is peeled off and the silicon wafer is immersed in a developer. After the immersion is completed, the silicon wafer is taken out, and a brush is used to remove the unexposed parts of the silicon wafer, especially the residual photosensitive blue oil between the convex lines, which needs to be cleaned. After the photosensitive blue oil is cleaned, the silicon wafer is rinsed with running water, and then the excess water is blown away with a hair dryer. The silicon wafer is dried in an oven to obtain the preparation of the positive mold of the chip integrated with microchannel microvalve. Finally, the chip positive mold is used as a mold, and silicone rubber AB glue is used for casting and mold turning to obtain a silicone rubber pipeline part chip (upper part), and then the silicone rubber surface is treated with air plasma and bonded with another thin film silicone rubber to obtain a microporous microvalve silicone rubber chip.

[0037] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a microporous microvalve silicone rubber chip by using a negative photosensitive adhesive, characterized in that: The following steps are involved: S1, use nylon mesh to apply PCB photosensitive blue oil on the silicon wafer; S2, placing the silicon wafer coated with blue oil in an oven to dry, and after drying, cooling to room temperature; S3, a film (negative film) printed with chip microchannels is pasted on the surface of the blue oil coating, the four corners of the silicon wafer are fixed with transparent tape, and exposed to ultraviolet light, then the film is peeled off, and the silicon wafer is soaked in developer. After soaking and developing, the unexposed part is cleaned with a brush and rinsed with running water; S4, taking out the rinsed silicon wafer and drying it in an oven; S5. Take another piece of nylon screen, lay it flat on a smooth plastic plate, take a small amount of photosensitive blue oil, scrape it over the entire screen (screen polyurethane scraper), keep the photosensitive blue oil moist, slowly lift the screen film with tweezers, and transfer it to the upper surface of the silicon wafer; S6, peeling off the silk screen film from the surface of the silicon wafer, and turning the silicon wafer upside down so that its upper surface faces downward in an inverted state, and placing the silicon wafer on the frame with the middle empty; S7, then transfer the silicon wafer to an oven for drying. After drying, take out the blue oil silicon wafer, align the original film closely with the blue oil coating surface, and expose it again; S8, peeling off the film on the silicon wafer, and soaking the silicon wafer in a developer, using a brush to remove the unexposed part after soaking, washing with running water, blowing away excess water with a hair dryer, and then drying in an oven, thereby obtaining the preparation of a positive mold of a chip integrated with a microchannel and microvalve; S9. Use the chip positive mold as a mold and cast silicone rubber AB glue to obtain a silicone rubber pipeline part chip (upper part). Then use air plasma to treat the silicone rubber surface and bond it with another thin film silicone rubber to obtain a microporous microvalve silicone rubber chip.

2. The method for preparing a microporous microvalve silicone rubber chip by preparing a negative photosensitive resin according to claim 1, characterized in that: The silicon wafer is a single-side polished silicon wafer, and the photosensitive blue oil in S1 is applied to the polished side of the silicon wafer.

3. The method for preparing a microporous microvalve silicone rubber chip by preparing a negative photosensitive resin according to claim 1, characterized in that: After washing with S3 running water, solidified blue oil raised lines appear on the silicon wafer, and the cross-section of the lines is rectangular.

4. The method for preparing a microporous microvalve silicone rubber chip by preparing a negative photosensitive resin according to claim 1, characterized in that: When the silk screen film is transferred to the upper surface of the silicon wafer with the convex lines, the silk screen film is made to fit and contact with the convex lines on the surface of the silicon wafer.

5. The method for preparing a microporous microvalve silicone rubber chip by preparing a negative photosensitive resin according to claim 1, characterized in that: When the silk screen film is peeled off from the surface of the silicon wafer, the photosensitive blue oil adhering to the raised lines on the silicon wafer is in a semi-fluid state.

6. The method for preparing a microporous microvalve silicone rubber chip by preparing a negative photosensitive resin according to claim 1, characterized in that: After placing the silicon wafer on the frame in S6, the silicon wafer needs to be left to stand for more than 10 minutes.

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