JPH04357133A - Processing of photosensitive glass - Google Patents

Abstract

PURPOSE:To improve efficiency and accuracy of processing of photosensitive glass by irradiating one surface of photosensitive glass with given laser, reflecting the transmitted laser by a reflecting mirror, passing into the other surface of glass, exposing and etching the exposed the part. CONSTITUTION:A photosensitive glass 1 having both the polished top and bottom surfaces 1a and 1b and a reflecting mirror 2 below the photosensitive glass are set side by side and irradiated with XeCl excimer laser at 280-350<nm> from an excimer laser oscillator 3 laid above the glass 1 and passed into the top 1a of the glass l. Then the laser transmitted in the glass 1 is reflected by the reflecting mirror 2, repassed from the bottom 1b into the glass 1, the laser is made to go and return to expose the glass 1. Then, after the exposure is completed, the glass is thermally developed at 500-700 deg.C, the exposed part is crystallized, sprayed with a solution of hydrogen fluoride in a showered state and etched to process the photosensitive glass.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing photosensitive glass by etching.

0002

2. Description of the Related Art Conventionally, there is a method of manufacturing ink jet printer heads and the like by etching photosensitive glass. This method involves exposing a desired part of the photosensitive glass to irradiation with an ultraviolet lamp (exposure process), heating the photosensitive glass to 500 to 700°C to crystallize the exposed area (thermal development process), and crystallizing the glass. In this method, the exposed areas are dissolved and removed using an etching solution (hydrofluoric acid solution). Note that a mercury lamp or the like is used as the ultraviolet lamp.

0003

FIG. 17 shows the spectral distribution of an ultra-high pressure mercury lamp, which is commonly called an ultraviolet lamp. According to this, mercury lamps have spectral distribution characteristics that cover not only ultraviolet rays but also a wide wavelength range.
Photosensitive glass is only sensitive to light with a wavelength of 280 to 350 nm. That is, when using a mercury lamp,
Since the spectrum in the wavelength range of 350 nm or more is not involved in the exposure of the photosensitive glass, much of the irradiation energy is wasted, the exposure efficiency is low, and the exposure time becomes long.

[0004] Therefore, in order to shorten the exposure time, as shown in FIG.
A possible method is to arrange a reflecting mirror 17 below the photosensitive glass 16, as shown in FIG. 2, to make the reflected light re-enter the lower surface of the photosensitive glass, thereby increasing the efficiency. However, in the method using the mercury lamp 18, the light emitted from the light source has a low straightness and travels with a spread of about ±1 degree. Therefore,
If the thickness of the photosensitive glass 16 to be exposed is thick, even if the light can be exposed accurately on the light incident surface 16a, the light will spread when passing through the inside of the glass. And the reflector 17
When the light is reflected by the light beam, enters from the opposite surface 16b, passes through the photosensitive glass again, and returns to the incident surface 16a, the light spreads far beyond the exposure range at the time of incidence. In this way, when the dimensional error of the exposed area becomes large, it becomes impossible to accurately remove only the desired area in the etching process.
Dimensional accuracy of processed products deteriorates. For the above reasons, in the conventional method using a mercury lamp, it is difficult to increase the efficiency of exposure using a reflecting mirror.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a processing method that can improve the efficiency and shorten the exposure process time, and can expose even thick photosensitive glass with high dimensional accuracy.

[0006]

[Means for Solving the Problems] The photosensitive glass processing method according to the present invention is characterized in that the oscillation wavelength is 280 to 350 nm.
A laser beam is irradiated onto one side of the photosensitive glass, and a reflecting mirror placed in parallel with the photosensitive glass reflects the laser beam that has passed through the photosensitive glass and makes it incident on the other side of the photosensitive glass. The method includes a step of exposing the glass to light and a step of etching the exposed portion of the photosensitive glass. Note that it is preferable to use a XeCl excimer laser as this laser.

[0007] If the exposed photosensitive glass is cut into a plurality of pieces in a direction perpendicular to the exposure direction, efficiency in obtaining a plurality of members made of photosensitive glass can be improved.

[0008] Furthermore, in the exposure step, if a plurality of laminated photosensitive glasses are exposed simultaneously, it is possible to improve efficiency when processing a large number of photosensitive glasses.

[0009] If exposure by laser irradiation is performed while the photosensitive glass is placed in a liquid having a refractive index comparable to that of the photosensitive glass, the precision of exposure is further improved.

0010

[Function] Lasers have good straight-line propagation, and for example, in the case of a XeCl excimer laser, the spread of light can be reduced to about ±0.02 degrees, so even in thick photosensitive glass, the spread of light inside the glass can be reduced. . Therefore, even if the laser passes through the photosensitive glass, is reflected by a reflecting mirror, and then enters the photosensitive glass again, it will pass through the photosensitive glass with the same dimensions as when it first entered, so there will be dimensional errors in the exposed area. does not occur.

[0011]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, a method for manufacturing an inkjet printer head made of photosensitive glass by the processing method according to the present invention will be explained step by step with reference to FIGS. 1 to 5. first,
As shown in FIG. 1, reflecting mirrors 2 are juxtaposed at intervals below a photosensitive glass 1 (a plate member with a thickness of 1 mm in this embodiment) whose upper and lower surfaces 1a and 1b are polished. Then, a XeCl excimer laser is irradiated from an excimer laser oscillator 3 provided above the photosensitive glass 1. As shown in FIG. 1, the XeCl excimer laser is emitted from the oscillator 3 and travels straight to the upper surface of the photosensitive glass 1.
incident on a.

When transmitted through the photosensitive glass 1, the reflecting mirror 2
and enters the photosensitive glass 1 again from the lower surface 1b. Then, the laser passes from the lower surface 1b of the photosensitive glass 1 toward the upper surface 1a, and travels upward. While reciprocating between the laser oscillator 3 and the reflecting mirror 2, the laser travels substantially straight. The photosensitive glass 1 is exposed to the laser light that reciprocates in this way.

Then, the photosensitive glass 1 is moved by a moving means (not shown), and the entire area to be etched is exposed to laser light, as shown in FIG.

When the exposure is completed, the photosensitive glass 1 is
Heating to a high temperature of about 0 to 700°C, as shown in Figure 3,
A heat development step is performed to crystallize the exposed portion 1c.

Next, this photosensitive glass 1 is etched by showering it with an etching solution consisting of a 5-10% solution of hydrofluoric acid (HF). At this time, by changing the time for applying the etching solution depending on the part of the photosensitive glass, the amount dissolved by etching is changed, and as shown in FIG. 4, an ink flow path 1d of a desired shape is formed. In this embodiment, ink channels 1d are provided on both sides of the photosensitive glass 1 by performing an etching process on both sides.

After the channel substrate 1 made of photosensitive glass is formed in this manner, a diaphragm 4 is attached so as to close the ink channels 1d on both the front and back surfaces, and a piezoelectric element 5 is further provided on the diaphragm 4. Thus, the inkjet printer head shown in FIG. 5 is completed. In this printer head, ink is filled into the ink flow path 1d from a supply means (not shown), and when power is supplied to the piezoelectric element 5, the diaphragm 4 vibrates and the ink in the flow path is pressurized. It stands out.

In the present invention, the photosensitive glass 1 is exposed using a laser as shown in FIG.
In the case of a Cl excimer laser), it can be made extremely small, and the light can be made to travel substantially straight. As a result, even if a somewhat thick photosensitive glass 1 is exposed by reciprocating laser light using the reflecting mirror 2, both the light incident surface 1a and the opposite surface 1b can be exposed with high precision. Therefore, when etching is performed on both sides, channels of the same shape can be accurately formed on both sides.

In the present invention, the photosensitive glass 1 is exposed from both the front and back sides by the laser irradiated from the oscillator 3 and the laser reflected by the reflecting mirror 2, so that the exposure time can be shortened. Note that the photosensitive glass 1 is 1
It is experimentally required that approximately 90% of laser light be transmitted per mm. Calculating based on this, in this example, the photosensitive glass 1 with a thickness of 1 mm is used, and approximately 81% of the laser light is transmitted in a 2 mm round trip.
Exposure can be performed with a light intensity of about 180% compared to the case where no reflecting mirror is used, and the exposure time can be shortened to about 55% of the conventional method. Further, since the light intensity on the incident surface 1a side and the opposite surface 1b side are made uniform, variations in exposure are eliminated.

FIG. 6 shows the spectral distribution of the XeCl excimer laser used in this example. The oscillation wavelength of this XeCl excimer laser is 308 nm, and the light intensity at other wavelengths is almost 0. That is, there is almost no spectrum other than the photosensitive region (wavelength 280 to 350 nm) of the photosensitive glass, and all of the irradiation energy is used for exposing the photosensitive glass. Therefore, exposure efficiency is better than that of a mercury lamp.

In this embodiment, the photosensitive glass 1 was exposed by direct laser irradiation, but the photosensitive glass may be irradiated with the laser after masking the portions that will not be exposed. Examples of such an exposure process are shown in FIGS. 7 and 8. That is, the photomask 1 includes a light-transmitting part 19a having the shape of the ink flow path 1d and a light-blocking part 19b having a shape other than that.
9 is placed on the photosensitive glass 1, and this photomask 1
The photosensitive glass 1 is irradiated with a laser through the laser beam 9. At this time, the laser enters the photosensitive glass 1 from the oscillator 3, is reflected by the lower reflecting mirror 2, and enters the photosensitive glass 1 again, so that the photosensitive glass 1 is efficiently exposed. Then, as shown in FIG. 8, the entire area of the light-transmitting portion 19a is irradiated with a laser. Thereafter, in the same manner as in the previous example, the ink flow path 1d shown in FIG. 4 is formed by the heat development process and the etching process shown in FIG. complete.

According to this method, the light-shielding portion 19b does not transmit the laser and the photosensitive glass in that portion is not exposed, so extremely fine processing such as the formation of a groove narrower than the width of the laser beam, such as the nozzle of an inkjet head, is possible. is possible. Further, by forming the photomask 19 with high precision, processing precision can be improved.

Furthermore, although it is optimal to use the XeCl excimer laser as described above, if the oscillation wavelength is 280~
As long as the wavelength is 350 nm, other excimer lasers, carbon dioxide lasers, etc. can also be used.

Next, a second embodiment of the present invention will be described. In FIG. 9, a block 6 of photosensitive glass having a thickness of about 5 mm is exposed to light by irradiation with a XeCl laser and reflection by a reflecting mirror 7, as in the first embodiment. When the exposure is completed, the block 6 is cut along the cutting line 8 and divided into small pieces 6a to 6e. To cut the block 6, a well-known slicing machine or dicing machine for cutting semiconductor wafers is used. After thermally developing the divided small pieces 6a to 6e, the small pieces 6a to 6e are lined up as shown in FIG. 10, and with one side covered with the protective member 9, an etching solution (not shown) is poured from above the drawing. Perform etching. When the etching on one side is completed in this way, the small pieces 6a to 6e are reversed and the other side is etched in the same manner. A plurality of small pieces 6a to 6 that have been subjected to the same processing on both the front and back sides in this way
get e.

According to this, the exposure process for a large number of small pieces 6a to 6e can be performed simultaneously, so that work efficiency is greatly improved and work time can be shortened. By performing a plurality of etching steps at the same time as shown in FIG. 10, the work time can be further shortened. Particularly, when manufacturing a large number of pieces of the same shape as in this embodiment, the work is extremely efficient.

[0026] Furthermore, in order to ensure proper light incidence during exposure, the surface of the photosensitive glass is polished;
Conventionally, when manufacturing a plurality of plate members, it was necessary to polish each plate member individually, but according to this embodiment, only the surface of the block 6 needs to be polished, reducing the number of times of polishing. Significantly reduced and work efficiency improved.

In this embodiment, since a 5 mm photosensitive glass block 6 is used, the transmittance of the laser beam is about 35% in a 10 mm round trip. Therefore, compared to the case where no reflecting mirror is used, exposure can be performed with 135% of the light intensity, and the exposure time can be shortened to about 74%.

FIG. 11 shows an example of this processing method in which the exposure step is performed using a photomask. That is, on the top surface of the photosensitive glass block 6, there is a transparent section 19a.
A photomask 19 consisting of and a light shielding part 19b is arranged,
A reflecting mirror 7 is disposed below the block 6, and the block 6 is irradiated with a laser through a photomask 19. The subsequent heat development process, etching process, etc. are the same as in the above example. In this way, by performing the exposure process using the photomask 19, extremely fine and precise processing is possible.

In the third embodiment shown in FIG. 12, a plurality of photosensitive glass plates 10a to 10e are laminated and a reflecting mirror 11 is arranged below them to expose them at once by irradiating and reflecting laser light. This is a method of doing this. This method also shortens the exposure process and improves work efficiency. In this embodiment as well, five 1 mm thick photosensitive glass plates are laminated, so that exposure can be performed at approximately 135% of the light intensity as in the second embodiment, and the exposure time can be shortened to approximately 74%. Further, as shown in FIG. 13, an exposure process can be performed using a photomask 19 to perform precise processing.

Since the light emitted from the laser travels in a very straight line, it can be used when the photosensitive glass is thick as in the second embodiment, or when multiple photosensitive glass plates are used as in the third embodiment. Even when the glass is laminated, the light hardly spreads even after passing through the glass and being reflected and re-transmitted, allowing accurate exposure from the top edge to the bottom edge. Therefore, the second
Small pieces 6a to 6e, 10a manufactured based on Example 3
~10e can be etched with good dimensional accuracy.

[0031] Since exposure is performed by irradiation with laser light and its reflection, uniform exposure can be performed on the upper surface side and the lower surface side of the exposed portion. Therefore, according to the second and third embodiments,
A plurality of photosensitive glass pieces 6a to 6 exposed to the same degree of light
e, 10a to 10e can be obtained.

As mentioned above, the transmittance of the laser beam changes depending on the thickness of the photosensitive glass, and the exposure efficiency is determined accordingly, so by appropriately setting the light intensity during irradiation and the glass thickness, The exposure time can be set as desired.

In the first to third embodiments, exposure was performed with the photosensitive glass placed in the air, but if the photosensitive glass was placed in a liquid with a refractive index similar to that of the liquid and exposed, The influence of light refraction at the end face of the photosensitive glass is small, allowing for more accurate exposure. An example is shown in FIG. According to this, a liquid 12 that has a refractive index close to that of photosensitive glass (refractive index 1.51117) and has good light transmittance, such as benzene (refractive index 1.5
A photosensitive glass plate 14 is placed in a container 13 filled with
a to 14e are inserted, and a reflecting mirror 15 is arranged below them. In this embodiment, a jig (not shown) is used to stack the glass plates 14a to 14e at intervals so that the liquid 12 is present in the gaps. When exposure is performed using a laser as in the third embodiment, the photosensitive glass plates 14a to 14e are exposed with high precision without being affected by the refraction of light on the surface of the photosensitive glass.

The liquid 12 containing the photosensitive glass only needs to have a refractive index of around 1.5 and high light transmittance, such as carbon tetrachloride (refractive index 1.4607) or paraffin oil (refractive index 1.48). ) can be used. Furthermore, in this embodiment, a plurality of photosensitive glass plates are stacked at intervals and placed in the liquid 12, but when only one plate member is exposed as in the first embodiment, Even when exposing a block as in the second embodiment, the accuracy can be improved by exposing the photosensitive glass in the liquid 12 in this way.

Of course, in this case, as shown in FIG. 15, the photosensitive glass plates 14a to 14 are
By performing laser irradiation on e, finer processing becomes possible.

As in the first to fourth embodiments above, when photosensitive glass is exposed using a laser whose oscillation wavelength is approximately 280 to 350 nm and a reflecting mirror, the spread of light is extremely small and processing accuracy is improved. At the same time, there is no waste in laser irradiation energy, and reflected light is also used.
Exposure is extremely efficient. In particular, when photosensitive glass is irradiated with laser through a photomask, more precise processing becomes possible.

[0037]

[Effects of the Invention] As described above, according to the present invention, since a laser is used to expose the photosensitive glass, the laser beam that has passed through the photosensitive glass is reflected by a reflecting mirror and transmitted through the photosensitive glass again. It is possible to perform exposure with high dimensional accuracy and high efficiency. Therefore, it is also possible to shorten the working time. Furthermore, since a laser oscillator that does not oscillate at wavelengths outside the sensitivity range of photosensitive glass is used, irradiation energy is not wasted and is efficient.

By dividing a block of photosensitive glass after exposure, or by exposing a plurality of photosensitive glasses at once in a stacked state, a large number of photosensitive glass members can be produced more efficiently in a shorter time.

If the exposure process is carried out with the photosensitive glass placed in a liquid having a refractive index similar to that of the photosensitive glass, it will be hardly affected by the refraction of light on the surface of the photosensitive glass, and it will be possible to achieve even higher precision. Exposure can be performed.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the exposure process of the first embodiment of the present invention.

[Figure 2] Front view of the photosensitive glass at the end of the exposure process shown in Figure 1

[Figure 3] Front view of photosensitive glass in the heat development process

[Figure 4] Cross-sectional view of photosensitive glass after etching process

[Figure 5]
Cross-sectional view of an inkjet printer head manufactured using photosensitive glass

[Figure 6] Spectral distribution diagram of xenon chloride excimer laser

[
FIG. 7 is a front view showing the exposure process using a photomask in the first embodiment

[Figure 8] Front view of the photosensitive glass at the end of the exposure process shown in Figure 7

FIG. 9 is a front view showing the exposure process of the second embodiment of the present invention.

FIG. 10 is a reduced front view showing the etching process of the second embodiment.

FIG. 11 is a front view showing the exposure process using a photomask in the second embodiment.

FIG. 12 is a front view showing the exposure process of the third embodiment of the present invention.

FIG. 13 is a front view showing an exposure process using a photomask in the third embodiment.

FIG. 14 is a front view showing the exposure process of the fourth embodiment of the present invention.

FIG. 15 is a front view showing the exposure process using a photomask in the fourth embodiment.

[Figure 16] Front view showing the conventional exposure process

[Figure 17] 50
Spectral distribution diagram of 0W ultra-high pressure mercury lamp

[Explanation of symbols]

1 Photosensitive glass 2 Reflector 3 Laser oscillator 6 Photosensitive glass 7 Reflector 10a, 10b, 10c, 10d, 10e Photosensitive glass 11 Reflector 12 Liquid 14a, 14b, 14c, 14d, 14e Photosensitive glass

Claims (5)

[Claims] Claim 1: A laser having an oscillation wavelength of 280 to 350 nm is irradiated onto one surface of a photosensitive glass, and the laser that has passed through the photosensitive glass is reflected by a reflecting mirror juxtaposed with the photosensitive glass. A method for processing photosensitive glass, comprising the steps of: exposing the photosensitive glass by exposing the photosensitive glass to the other surface of the photosensitive glass; and etching the exposed portion of the photosensitive glass. 2. The method of processing photosensitive glass according to claim 1, wherein the laser is a XeCl excimer laser. 3. The method of processing photosensitive glass according to claim 1, further comprising the step of cutting the exposed photosensitive glass in a direction perpendicular to the exposure direction to divide it into a plurality of pieces. 4. The method of processing photosensitive glass according to claim 1, wherein the exposure step is carried out simultaneously on a plurality of laminated photosensitive glasses. 5. The exposure step is characterized in that the laser irradiation is performed while the photosensitive glass is placed in a liquid having a refractive index similar to that of the photosensitive glass. 4. The method for processing photosensitive glass according to any one of 4 to 4.