JP2000002612A - Collective manufacture of pressure capacitance transducer made of glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize manufacture of transducers in a batch unit, by forming a plurality of pressure sensors for composing the transducers by sputtering an electrode pattern on a glass plate, and by separately breaking them into individual sensors. SOLUTION: The collective manufacture of pressure capacitance transducer with a glass diaphragm or the like in a batch unit is started from a glass sheet with a thickness based on a pressure range or the like. For example, the glass sheet is set to a plate with specific dimensions by a breaking along a scratch line, and a capacitor electrode or the like is formed on the plate by sputtering treatment. Then, glass frit or a crossover tab such as silver are screen-printed. Each plate for forming a capacitor is fixed for treating in a vacuum oven, pressure in the capacitor is reduced, and at the same time, a joint part is sealed. The jointed plate is subjected to, for example, a pressure cycle test or the like and is broken along the scratch line, thus obtaining a number of sensors.

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 pressure transducer, particularly a glass pressure capacity transducer, in batches.

[0002]

BACKGROUND OF THE INVENTION U.S. Pat. No. 5,189,591 to Bellnott, assigned to the assignee of the present application, discloses a method for manufacturing aluminosilicate glass pressure sensors and similar sensors one at a time. Obviously, if such a sensor could be manufactured in batches, it would be clear that the manufacturing costs could be reduced. U.S. Pat. No. 5,317,919 to Autrey discloses one method of batching glass sensors. In this method, a well-known photolithographic etching technique is employed to form a conductive coating.

On the other hand, there is still a need for a new method of manufacturing such a glass sensor in batches.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for manufacturing a glass sensor in batches.

[0005]

According to the present invention, this object is achieved in the following steps: a step of scratching a glass plate, a step of spattering an electrode pattern on the plate, and a step of spattering. Screen printing a glass frit and a crossover tab thereon. The plates are pre-glazed and glued together to form a plurality of sensors. The plate is then broken along the scratch line to obtain the sensor.

[0006] Other objects, features and advantages of the present invention are set forth in the following detailed description of preferred embodiments of the invention, which will be apparent as the description proceeds with reference to the accompanying drawings.

[0007]

DETAILED DESCRIPTION OF THE INVENTION U.S. Pat. No. 5,189,591 to Vernott, issued Feb. 1993 and assigned to Allied Signal Inc., is disclosed herein by reference. The present invention provides a capacitive pressure transducer made of aluminosilicate glass.

A glass pressure sensor or transducer 10 according to the present invention is shown in FIGS. The glass pressure transducer 10 includes a top diaphragm 12 and a bottom diaphragm 14, which are made of glass,
Preferably Corning # 1723 or # 1737F
Made of aluminosilicate glass like. The ground shield portions 18 and 24 are provided on the outer surfaces of the diaphragms 12 and 14. The electrode 20 is provided on the inner surfaces of the diaphragms 12 and 14. The crossover metal tab 26 is preferably made of silver and serves as a conductor extending from the electrode 20 to the top lead 21. Also crossover metal tab 2
6 can also be made of other metals such as palladium or gold. The electrode 22 is connected to the lead 23 of the bottom electrode. A grounding lead wire 25 can be added. The leads 21, 23, 25 are preferably made of platinum. Although not shown, another lead may be connected to the lead described above. The shape of the electrodes 20, 22 can be circular or square, and can form a standard capacitor. Ground shield portions 18 and 24 and electrodes 20 and 2
2 is made of a noble metal, preferably platinum.

The diaphragms 12, 14 are joined together,
The electrodes 20 and 22 form a capacitor. This bonding is performed by hydration bonding or glass fritting. The frit glass 30 functions as a spacer between the diaphragms 12 and 14 and as a sealing part forming a cavity 32 between the diaphragms. The cavity 32 is decompressed,
Vacuum or other reference pressure.

Referring to FIG. 3, a three-membered accelerometer 40 is provided with a glass, preferably aluminum silicate, ground vibration mass 42 on top and bottom diaphragm 1.
The pressure transducer 10 can be formed by being mounted between 2 and 14. The ground vibration mass body 42 includes an electrode 44 provided to face the electrode 20 and an electrode 4 provided to face the electrode 22.
6. The ground vibration mass 42 is separated from the diaphragm 1 by a frit 48 in such a manner that a cavity 49 is formed.
2, 14 are joined.

Referring to FIGS. 4 and 5, the glass pressure transducer 10 or accelerometer 40 and other similar transducers and accelerometers can be manufactured in batches at low cost as follows. The method begins with an uncoated glass sheet such as aluminum silicate glass, Corning # 1737F. The thickness of the glass is selected based on the pressure range of the sensor. For example, 2
With a 0 psi sensor, the thickness could be 0.5 mm. The glass sheet is scratched in step 50 and broken in step 52 to form a 6 x 6 inch square plate, preferably 5 x 6 inches.
Created on a 3/4 x 5.33 / 4 inch plate. If desired, the spaced cavities, as illustrated in the aforementioned U.S. Pat. No. 5,189,591, are etched into glass. Each plate is then subjected to a cleaning process, including a spin rinser dryer and an ozone cleaning, for approximately 60 minutes at steps 54 and 56, but the cleaning process is not limited to the cleaning described above.

To form the diaphragm 12, an aperture mask 100 is fixed on top of a glass plate 102,
An aperture mask 104 is fixed to the bottom of the glass plate 102. Depending on the type of spattering equipment used, each side of the plates 102, 114 may be sputtered separately, or both plates may be sputtered simultaneously. If sputtered separately, the plate is ozone washed during the spattering process. In the case of the diaphragm 14, the aperture mask 116
Is fixed to the bottom of the glass plate 114, and the aperture mask 112 is fixed to the top of the glass plate 114. Plate 60 with each mask in step 60
2, 114 are inserted into a well-known spattering device,
Here, a pre-etching process is performed for 5 to 10 minutes. The pattern of the opening mask 100 is sputtered on the glass plate 102 to form the ground shield portion 18,
The pattern on the opening mask 104 forms the electrode 20.
Similarly, the pattern of the opening mask 116 is the glass plate 1
The bottom shield 14 is sputtered to form the ground shield 24, and the aperture mask 112 constitutes the electrode 22. The preferred sputtering gas is argon.
The pattern is deposited to a thickness of 750-1000 Angstroms, preferably 1000 Angstroms. The deposition is performed at a partial pressure of oxygen. Other methods and materials can be used for vapor deposition, for example, electron beams, ion beams or organometallics. In order to increase the yield as an option, the silicon dioxide insulator 110 can be sputtered on the electrode 22 to a thickness of 1000 angstroms.

In the next step 66 after the inspection step 64, a glass screen fritting process is performed over the bottom surface of the glass plate 102. Glass frit 106 is selected to match the glass. For Corning 1737,
Glass frit Corning 7574 or Semicom S
CB1 can be used. The glass frit 106 is applied by a well-known screen printing device and preferably has 325 mesh or more. On the other hand, the mesh varies depending on the pressure range of the sensor. Another 200 or 250 can be used as a mesh. Crossover metal tab 108 is also screen printed on top of glass plate 114 with the same mesh as the glass frit.

What is important after screen printing is that the screen-printed frit (as opposed to the crossover tab) settles out, causing protrusions or small voids to spread out and become smooth. Step 68 is performed by allowing the frit to settle for about 30 minutes, and then in step 70 the frit is dried at 150 ° C. The fritted plate is then transferred to a flat quartz plate at step 72, slightly wrapped, polished to 5 microns for a few seconds to remove the high spots on the dried frit,
It is beautifully wiped off with a lintless wipe. The crow plate 114 having the silver crossover tab is also beautifully wiped off. Both plates 102, 114 are pre-glazed in an oven or furnace at step 74. A typical pre-gloss step is from 25 ° C (room temperature) to 5 ° C for about 1 hour.
Heat to 70 ° C, maintain a constant temperature of 570 ° C for about 45 minutes, heat to about 640 ° C for about 30 minutes, maintain a constant temperature of 640 ° C for about 30 minutes, turn off the heater in the oven and allow Cooled.

Optionally, a manual lap is applied over the polished flat light surface for a few seconds to remove high spots on the frit.

In step 76, the glass plate 114 is secured to the glass plate 102 at a pressure of about 3 psi per clip using a fixture with Inconel clips so that the frit faces the silver tab. Once properly aligned, the fixture is transferred to a vacuum furnace. In step 78, the furnace is evacuated to a vacuum (pressure less than 100 mil torr).
The plates are then sealed together by heating from room temperature to about 600 ° C. for a period of 60 ± 10 minutes. Maintain at 600 ° C. for about 15 ± 1 minute. Maintain at 680 ° C. for about 45 ± 1 minutes. The heater is turned off to cool naturally. Below 400 ° C., the furnace is open to the atmosphere. All the temperatures mentioned in this step can be varied in the range of ± 50 ° C.

In step 80, the fixture is removed and the frit seal is inspected. Optionally, a pressure cycle test is performed at step 82. The fixed body is placed in the pressure chamber,
Cycling over the sensor operating pressure leaves pressure hysteresis.

In step 84, the joined plates are scratched, transferred to a break table, and broken along the scratch line to obtain a number of sensors. After being visually inspected at step 86, the sensor is mounted on the pressure housing base at step 88.

Various modifications to the preferred embodiment described above will be apparent to those skilled in the art. Accordingly, the disclosure of the present invention is intended to be illustrative only and is not intended to limit the scope and spirit of the invention, which is set forth in the following claims.

[Brief description of the drawings]

FIG. 1 is a top plan view of a glass pressure transducer manufactured by the batch method according to the present invention.

FIG. 2 is a side view of the pressure transducer of FIG.

FIG. 3 is a side view of a glass accelerometer manufactured by the batch method according to the present invention.

FIG. 4 is a flow chart of the batch method according to the present invention.

FIG. 5 shows components used to make the pressure transducer of FIG. 1 using the method according to the invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Glass pressure transducer 12, 14 Diaphragm 18 Ground shield part 20 Electrode 21, 23, 25 Lead wire 30 Flit glass 32 Cavity part 40 Accelerometer 42 Ground vibration mass body 44 Electrode 46 Electrode 48 Flit 100 Opening mask 102, 114 Plate 104 Opening Mask 106 glass frit 108 crossover metal tab 110 silicon dioxide insulator 112 opening mask 114 glass plate 116 opening mask

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Raymond H. NISKA USA Arizona 85234, Gilbert, E. Chiapala Street 15836 (72) Inventor Nicholas F. Schmidt United States 85028 Arizona, Phoenix, E. Sunnyside Drive 3906 F-term (reference) 2F055 AA40 BB20 CC02 DD07 EE25 FF43 GG01 GG11

Claims (10)

[Claims] (A) scratching the first and second plates of uncoated glass; (b) cleaning the first and second plates; and (c) forming the electrode pattern. Fixing the first opening mask having the first opening mask to the first side of the first plate; and (d) fixing the second opening mask having the electrode pattern to the first side of the second plate. (E) sputtering the electrode pattern on the first side of the first and second plates, (f) removing the first and second aperture masks, and (g) removing the first and second aperture masks. Screen printing glass frit on a first side of one plate; (h) screen printing a crossover tab on a first side of a second plate; Work to pre-polish the second plate And (j) securing the first and second plates together and contacting the first respective sides; and (k) sealing and bonding the first and second plates to form the plurality of sensors. A method of manufacturing a glass pressure-capacity transducer in batches, comprising a forming step and (l) a step of forming a large number of sensors by breaking along a line for scratching a bonded plate. 2. A step of fixing a third opening mask having a polished shield pattern to a second side of the first plate, and a step of fixing a fourth opening mask having a polished shield pattern to a second side. Securing to the second side of the plate, sputtering the polished shield pattern on the second side of the first and second plates, and removing the third and fourth aperture masks Performing the method of claim 1. 3. The method of claim 2 wherein the step of spattering comprises the step of spattering and etching. 4. The method of claim 1, wherein the cleaning step includes ultrasonic cleaning, scratching and ozone cleaning. 5. The method of claim 1 including the step of spontaneously depositing the frit after step (g). 6. The method of claim 5 further comprising the step of drying the frit after the depositing step and lapping the frit by hand. 7. The method of claim 1, further comprising, after step (f), sputtering the silicon dioxide insulator on one of the first sides. 8. The method according to claim 8, further comprising: after step (l), mounting the sensor on a base portion of the housing.
the method of. 9. The method of claim 1 wherein step (k) includes heating the plate in a vacuum. 10. The method of claim 1, further comprising the step of performing a pressure cycle test on the plate after step (k).
the method of.