JP4262975B2 - Manufacturing method of glass substrate microchip - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The invention of this application relates to a method for manufacturing a glass substrate microchip.
[0002]
[Prior art]
Form a micro-channel (channel) in a transparent substrate such as glass and use it as a liquid or gas channel, and perform operations such as chemical reaction, separation, mixing, and analysis in the micro-channel region Microchips for microfluidic manipulation that have been used are attracting attention as being useful in a wide range of fields such as analytical chemistry, chemical synthesis, and biochemistry. In fact, many remarkable results have been obtained so far by research using the microchip by the inventors of this application.
[0003]
Such a microchip substrate is considered to be practically composed of glass because it is chemically inert and has high translucency.
[0004]
Usually, a microchip using this glass as a substrate is manufactured by laminating two glass substrates after forming grooves on the surface portion of the substrate to form a fine channel. For example, as shown in FIG.
1) A Cr (chromium) / Au (gold) layer is vapor-deposited on the surface of the glass substrate, and then a photoresist is applied.
2) After performing photolithography, 3) develop and process the mask into a predetermined pattern,
4) Etching of Au / Cr layer,
5) Etching the glass 6) Removing the Au and Cr layers,
Grooves for fine channels having a predetermined pattern are formed on the surface of the glass substrate. Of course, the fine channel includes a port portion such as a liquid reservoir, a confluence portion, a branch portion, an inlet portion for a sample, a reagent and the like, a drain port for discharging and exhausting, and the like.
[0005]
Next, as shown in FIG. 4, another glass substrate (B) is bonded to the obtained glass substrate, that is, the glass substrate (A) in which the fine channel is grooved on the surface portion. This bonding is usually performed by heating up to about 650 ° C. with a heating time of about 1 hour, holding at this temperature for about 5 hours, and then slowly cooling to room temperature over about 10 hours. Yes.
[0006]
This bonding process greatly affects the yield of glass substrate microchip products and the quality of chips, and so far, hydrogen fluoride has been used to control heating conditions and clean surface parts. : The idea of combined use of HF has also been made (References 1 to 3).
[0007]
However, the conventional glass substrate bonding process as described above requires a long time of, for example, 16 hours, and the remaining photoresist or Au / Cr deposited film is bonded. Since it causes defects and leads to a decrease in yield, an extremely high treatment for cleaning the glass surface, which is a treatment with HF, is required, and there has been a big problem as a mass production technique.
[0008]
[Literature]
1: Proceeding of μ-TAS '98, 311-314 (1998)
2: Proceeding of Micro Electro Mechanical System '97, pp.299
3: JP-A-10-338555
[Problems to be solved by the invention]
Therefore, the invention of this application eliminates the problems of the prior art as described above, and requires high-throughput, short-time, high yield, and conventional means for advanced surface cleaning. An object of the present invention is to provide a new method capable of manufacturing a glass substrate microchip by bonding without doing so.
[Means for Solving the Problems]
In order to solve the above problems, the invention of this application is as follows. First, a glass substrate is formed by joining two glass substrates each having a fine channel formed in the surface of at least one glass substrate. A method of manufacturing a microchip, wherein an exhaust trench corresponding to a glass substrate outlet is formed at a heating temperature equal to or lower than a softening point of a glass substrate in a reduced pressure environment having a degree of vacuum of 10 ⁻¹ Torr to 10 ⁻⁴ Torr. There is provided a method for producing a glass substrate microchip, characterized in that a glass substrate is tightly bonded by press-pressing through a contact plate .
[0010]
In the invention of this application, as for the above-mentioned method, secondly, heating and pressurization are performed with a pressing force in the range of 1 to 100 kg / cm ^{2 at} a temperature lower by 50 ° C. to 100 ° C. than the softening point of the glass substrate. It provides a process for producing a glass substrate microchip, characterized in that, in the third, a method of manufacturing a glass substrate microchip which is characterized in that which has been constructed by the abutment plate Gagu Rafaito, 4 The present invention provides a method for manufacturing a glass substrate microchip, wherein two glass substrates to be bonded together are set as a set, and each of a plurality of glass substrates is simultaneously tightly bonded.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The invention of this application has the features as described above, and an embodiment thereof will be described below.
[0012]
In the invention of this application, for example, as illustrated in FIG. 1, two glass substrates (A) (in which a fine channel (C) is formed in a groove in the surface portion of at least one glass substrate (A) in advance. When bonding B), the glass substrate (A) is heated by a pressure below the softening point of the glass substrate (A), and is pressurized by a press (D) in a reduced-pressure environment at a low vacuum of 10 ⁻⁴ Torr or more. .
[0013]
In this case, the glass substrate (B) is not limited to the example shown in FIG. Further, the fine channel (C) can be formed by the conventional photoresist etching or the like as described above, and the fine channel (C) has an appropriate cross-sectional shape and plane arrangement pattern. Good.
[0014]
In the joining method of the invention of this application, the glass substrate is heated to a temperature below the softening point of the glass substrate, which is considerably lower than the conventional heating temperature of 650 ° C. This is because, for example, in the case of Pyrex (registered trademark) glass, the softening point is about 570 ° C., but in the invention of this application, a temperature lower than this temperature, for example, about 50 ° C. to 100 ° C. should be adopted. Can do.
[0015]
Further, in the bonding method of the invention of this application, a reduced pressure environment with a low vacuum degree of 10 ⁻⁴ Torr or more is employed. For example, the environment has a degree of vacuum of about 10 ⁻¹ to 10 ⁻⁴ Torr, more preferably about 10 ⁻³ Torr. In such a low vacuum environment, pressurization is performed by a press (D) as shown in FIG. 1 at a heating temperature equal to or lower than the softening point. In this case, the pressurization degree is the above-described vacuum degree or heating temperature. which varies depending condition, typically a pressure in the range of 1kg / cm ² ~100kg / cm ² is considered. Preferably will be a range of 5kg / cm ² ~50kg / cm ² is exemplified.
[0016]
In the method of the invention of this application, the close bonding of the two glass substrates (A) and (B) is realized as having practically sufficient bonding strength. Moreover, the process time for the bonding can be completed in several hours, for example, 1 to 3 hours, depending on the plane size of the glass substrate. Further, it is more characteristic that the fine channel (C) that is indispensable in the microchip is not deformed, broken, or damaged even by pressurization. This is a very important feature.
[0017]
Naturally, it is emphasized that the method of the invention of this application does not require a high-level surface cleaning treatment such as a conventional HF treatment.
[0018]
Even if the Au / Cr vapor deposition film remains on a part of the surface portion of the glass substrate, good adhesion bonding is realized. Of course, if desired, processing with HF or the like may be additionally performed.
[0019]
Further, in the invention of this application, for example, as shown in FIG. 1, the abutment having an exhaust opening (E) of the glass substrate, that is, an exhaust trench (F) corresponding to an opening for discharging liquid or gas. It is also effective to press with a press (D) with a plate (G) interposed. In this case, the contact plate may be used for the purpose of preventing damage due to pressurization of the press (D) on the glass substrate, improving heat conduction, and the like. At the same time, it is effective for exhausting from the fine flow path (C) of the glass substrate. An example of such a contact plate (G) is a hard graphite plate. Of course, the above contact plate may not be used.
[0020]
In the invention of this application, it is needless to say that the two glass substrates to be bonded may be set as a set and a plurality of sets may be bonded simultaneously without being limited to the example of FIG. Further, for example, 3 sheets of glass substrates as a pair, like the close contact in each of the opposed surface portion is possible as.
[0021]
Then, an Example is shown below and invention of this application is demonstrated in detail. Of course, the invention is not limited by the following examples.
[0022]
【Example】
As shown in FIG. 1, another Pyrex (registered trademark) glass substrate (B) was joined to the Pyrex (registered trademark) glass substrate (A) in which the fine channel (C) was formed. The degree of vacuum at that time was 10-3 Torr, and the press pressure was 6 kg / cm ² . Heating was performed according to the time pattern of FIG. That is, the temperature was raised to 500 ° C. in about 15 minutes, held at 500 ° C. for 1 hour, then lowered in temperature in about 15 minutes, and the bonding was completed in 90 minutes as a whole.
[0023]
In addition, the cleaning process by HF etc. is not performed previously with respect to the surface of a glass substrate (A).
[0024]
Through the above bonding, a glass substrate microchip having a bonding strength of about 4 to 7 MPa is obtained.
[0025]
【The invention's effect】
As described above in detail, the invention of the present application eliminates the problems of the prior art, requires high throughput, a short time and a high yield, and requires a conventional means for high-level surface cleaning. Without doing so, the glass substrate microchip can be manufactured by bonding.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view illustrating the method of the invention of this application.
FIG. 2 is a diagram showing a time pattern of heating temperature as an example.
FIG. 3 is a process cross-sectional view illustrating a method of forming a fine channel.
FIG. 4 is a schematic sectional view showing a conventional bonding method.

Claims (4)

A method of manufacturing a glass substrate microchip by joining two glass substrates each having a micro-channel formed in a surface portion of at least one glass substrate, the degree of vacuum being 10 ⁻¹ Torr to 10 ^{− In} a reduced pressure environment of ⁴ Torr, the glass substrate is closely bonded by press-pressing through a contact plate having an exhaust trench corresponding to the discharge port portion of the glass substrate at a heating temperature below the softening point of the glass substrate. A manufacturing method of a glass substrate microchip. ^2. The method for producing a glass substrate microchip according to claim 1, wherein heating and pressurization are performed at a temperature lower by 50 to 100 [deg.] C. than the softening point of the glass substrate by a pressurizing force in the range of 1 to 100 kg / cm < ² >. Contact plate Gagu Rafaito process according to claim 1 or 2 glass substrate microchip is characterized in that which has been constructed by. 4. The method of manufacturing a glass substrate microchip according to claim 1, wherein two glass substrates to be bonded are set as a set, and a plurality of sets of glass substrates are simultaneously tightly bonded.

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