JPH0579460A - Manufacture of micropump - Google Patents

Abstract

PURPOSE:To prevent entrance of contaminants to a pump by laminating a plastic film to a glass base sheet when a laminate is separated into individual pumps after base sheets are joined together, in a substance wherein a silicone base sheet to which a diaphragm part is attached is nipped between upper and lower glass base sheets. CONSTITUTION:A monocrystal silicone base sheet 1 is etched from both surfaces by means of a potasium hydroxide solution by using a substance produced by applying photolitho patterning on a thermal oxidation film by means of hydrofluoric acid and serving as a mask. In this way, a plurality of micropump structures having a diaphragm part, a valve, and a flow passage part are formed. After the thermal oxidation film, except a pressurized part on the upper surface of a valve, is dissolved for removal by means of hydrofluoric acid, upper and lower glass base sheets 4 and 5 are joined on both surfaces of the silicone base sheet 1 by an anode jointing method to produce a lamination base sheet on which a plurality of micropumps are formed. Thereafter, a plastic film 7 is stuck on the glass base sheet 5 side in which hole parts 6 for inflow and delivery of a pump are formed, and the laminate is cut and separated into individual micropumps by means of a dicing blade 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a micropump, and more particularly, as a device for precision fluid control to which micromachining technology is applied, a method for manufacturing a micropump which is expected to be put to practical use in the fields of medicine, analysis and the like. It is about.

[0002]

2. Description of the Related Art The micromachining technology as described above is
It is currently under development as a pioneer in advanced new technology fields.

The application of micromachining can be considered to be applied to many fields, and as a field where research is progressing specifically for practical use, there are fluid control devices such as micropumps and microvalves.

There are various types of micropumps based on the micromachining technique, such as piezoelectric type and electrostatic type, but the basic structure is almost the same. As shown in FIG. 1, a silicon substrate is etched from both sides to form a diaphragm. Part and valve part are formed and processed into a three-dimensional structure, then this silicon substrate is sandwiched between the upper and lower glass substrates and joined together by an anodic bonding method, etc. to fabricate a micropump with a flow path and a valve formed. I can.

In manufacturing a micropump (device) by such a micromachining technique, a plurality of micropumps are formed on a silicon wafer substrate by a photolithography process and bonded to upper and lower glass substrates to complete a micropump structure. After that, it is cut into individual micropumps and separated.

[0006] In this step, a method of fixing the substrates joined by using a wax to a cutting device table and cutting and separating the substrates has been conventionally performed.

[0007]

However, in the above-mentioned prior art, since the wax is used and the wet dicing process is performed, the wax remaining from the holes for the inflow and the outflow of the fluid formed in the glass substrate. Fine grinding powder from inspection and dicing penetrates into the micro pump as contamination,
It is impossible to completely remove even by cleaning, and the performance as a micropump that controls a minute amount of liquid is greatly deteriorated, such as a leak from the valve portion.

[0008] Also, pasting the work with wax,
The productivity was remarkably low due to the peeling process, the cleaning process of individual micropumps that were individual products, a complicated process, and handling problems.

The present invention solves such a problem, and its purpose is to prevent the inflow of fluid in the cutting process of the micropump and the contamination from the discharge hole portion to improve the product quality and yield. In addition to improving the productivity by shortening the process, it is possible to significantly improve the handling including the post process such as assembly.

[0010]

In order to solve the above problems, in the process of cutting and separating a bonded substrate on which a plurality of micropumps are formed in the manufacture of the micropump of the present invention, a fluid for inflow and outflow is used. Cutting and then laminating a plastic film on the glass substrate side where the through holes are formed, or joining and break separation after pre-grooving the glass substrate and silicon substrate to separate each micro pump. Is characterized by.

[0011]

According to the present invention, in the cutting and separating steps of the micropump, a plastic film is laminated on the glass substrate side where the fluid inflow and discharge holes are formed, and then the cutting process is carried out. Then, it became possible to prevent the residual glass of wax from the holes for inflow and discharge, the fine glass by the dicing process, or the grinding powder of silicon from entering the micropump as contamination.

Further, a silicon substrate on which a micropump structure is formed is formed by dicing the glass substrate and the silicon substrate after performing a groove process for break cutting and separating into individual micropumps in advance and then bonding the micropump structure. Since it is not exposed to the cutting process like the above, and since it is processed as a single item even when grooving the glass substrate, it is possible to easily wash and remove contaminants after grooving processing, excellent performance It became possible to manufacture a micro pump stably.

Further, by vacuum chucking the work laminated with the plastic film to the apparatus table, pasting and peeling of the work by the conventional wax,
It is possible to eliminate the complicated and time-consuming processes such as the cleaning process after the separation of individual products, and it is possible to greatly improve the productivity.

[0014]

【Example】

(Embodiment 1) FIG. 1 is a schematic sectional view of a micropump manufacturing process for explaining Embodiment 1 according to the present invention.

FIG. 1A shows a φ4 inch single crystal silicon substrate having a crystal orientation (100) and a thickness of 350 μm, which is obtained by photolithographically patterning a thermal oxide film (silicon dioxide) with 7% hydrofluoric acid. 70 degrees Celsius
A plurality of micropump structures having a diaphragm portion, a valve portion, a valve portion, and a flow passage portion are formed by etching from both sides with a 30% potassium hydroxide solution.

Next, the thermal oxide film used as the mask was dissolved and removed with hydrofluoric acid except for the preload portion on the upper surface of the valve portion (FIG. 1 (b)).

On both sides of this silicon substrate, upper and lower glass substrates having a thickness of 1 mm were applied at a voltage of 500 V at 350 ° C., and joined by an anodic bonding method to form a φ4 inch laminated substrate on which a plurality of micropumps were formed. (FIG. 1 (c)).

Next, a plastic film with an adhesive is attached to the side of the glass substrate on which the inflow and discharge holes of the pump are formed, and after vacuum adsorption to the table of the dicing machine, it is shown in FIG. 1 (d). In order to separate into individual micropumps, this laminated substrate is cut from the upper glass side. At this time, the dicing blade is set to a height at which the processing stops on the upper surface of the plastic film laminated on the lower side. After dicing, each micro pump separated on the plastic film is washed and dried in a bonded state, and peeled from the plastic film is irradiated with UV (80 W / cm × 15 W) on the film side.
Second) to reduce the adhesive strength of the film,
It was completely separated into individual micropumps, and finally, a piezo element for driving was attached to the diaphragm part, and a pipe for inflowing and discharging fluid was attached to the glass hole part to complete the process.

(Embodiment 2) FIG. 2 is a schematic cross-sectional view of a micropump manufacturing process for explaining Embodiment 2 according to the present invention.

FIG. 2A shows a plurality of micropump structures each having a diaphragm portion, a flow passage portion, and a valve portion formed on a φ4-inch single crystal silicon substrate having a thickness of 350 microns by the same process as in the first embodiment. Although formed individually, in the case of this example, at the same time, V-shaped grooves required for cutting and separating into individual micropumps were also formed.

Next, the thermal oxide film used as a mask was dissolved and removed with hydrofluoric acid except for the portion of the upper surface of the valve portion which was to be preloaded (FIG. 2B).

Further, a glass substrate having a thickness of 1 mm to be fitted to a silicon substrate is also preliminarily prepared by dicing or the like.
Grooving is performed at a depth of 7 mm (Fig. 2
(C)).

The silicon substrate thus formed and the upper and lower glass substrates are joined by an anodic bonding method (400 ° C., 750 ° C.).
V), a φ4 inch laminated plate on which a plurality of micropumps are formed (FIG. 2D).

By breaking along the already formed grooves of this laminated plate, the micro-pumps are separated into individual micro-pumps, and finally, a piezo element for driving is provided in the diaphragm part, and a fluid is flown into and discharged from the glass hole part. It was completed by attaching the pipe for.

[0025]

As described above, according to the present invention, in the cutting and separating step in the manufacture of the micro pump, the inflow of the fluid,
After laminating the plastic film on the glass substrate side where the discharge holes are formed, a method of cutting, or by performing a groove processing for cutting the glass substrate and the silicon substrate into breaks into individual micropumps in advance, Wax residue in dicing cutting, etc.
It is possible to prevent contaminants such as grinding powder from entering the micro pump, and it is possible to stably manufacture products that satisfy the performance as a pump.

Further, the productivity and the yield can be greatly improved by eliminating the processes such as the process of sticking the substrate with the wax, the process of peeling the substrate, the process of cleaning the product in a separated state, the process of drying, and the like, which requires a lot of steps including handling. I was able to do something.

[Brief description of drawings]

FIG. 1 is a diagram showing a manufacturing process of a micropump according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a manufacturing process of a micro pump according to a second embodiment of the present invention.

[Explanation of symbols]

 1,11 Silicon substrate 2,12 Thermal oxide film (silicon dioxide) 3,14 Preload part 4,15 Upper glass substrate 5,16 Lower glass substrate 6,19 Inflow hole 7 Laminate plastic film 8 Dicing blade and processing groove 9,20 Piezo element 10,21 Discharge pipe 13 Silicon substrate separation groove 17,18 Glass substrate separation groove

Claims (8)

[Claims] 1. A method of manufacturing a micropump having a structure in which a silicon substrate on which a diaphragm, a flow path, and a valve portion are formed is sandwiched between upper and lower glass substrates, and a silicon substrate on which a plurality of micropump structures are formed. A method for manufacturing a micropump, comprising laminating a plastic film on a side of a glass substrate having a liquid inflow / discharge hole portion in a step of cutting and separating the upper and lower glass substrates into individual micropumps. 2. A step of laminating a plastic film on a side (lower side) of a glass substrate having a liquid inflow / ejection hole portion, and then cutting from a surface on the opposite side (upper side), the cutting depth is laminated. 2. The method for manufacturing a micropump according to claim 1, wherein the process is performed up to the lower glass substrate on the plastic film or halfway through the thickness of the lower glass substrate. 3. A plastic film laminated on the side of the glass substrate having a liquid inflow / discharge hole is attached to the glass substrate with an adhesive, and the cut plastic film is peeled after irradiation with ultraviolet rays (UV). The method for manufacturing a micropump according to claim 1, wherein the method is for manufacturing a micropump. 4. A method of manufacturing a micropump having a structure in which a silicon substrate having a diaphragm, a flow path, and a valve portion is sandwiched between upper and lower glass substrates, and a silicon substrate having a plurality of micropump structures formed thereon. After joining the upper and lower glass substrates, in the process of separating into individual micropumps, the upper and lower glass substrates were previously grooved for cutting and separating into individual micropumps, and then joined to the silicon substrate. And a method for manufacturing a micropump. 5. A groove for preliminarily cutting and separating the silicon substrate into individual micropumps in the step of separating the individual micropumps after bonding the silicon substrate on which a plurality of micropump structures are formed and the upper and lower glass substrates. A method for manufacturing a micropump, comprising: forming a film by anisotropic etching, and then joining the film to a glass substrate. 6. The method for manufacturing a micropump according to claim 1, wherein the step of cutting and separating into individual micropumps is a chocolate break method. 7. The method for manufacturing a micropump according to claim 1, wherein the method of grooving for cutting and separating into individual micropumps is dicing or scribing. 8. The method of joining a silicon substrate and upper and lower glass substrates is anodic bonding.
A method for manufacturing the described micropump.