JP3143832B2 - Processing method of photosensitive glass - Google Patents

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 has been a method of forming a fine shape such as an ink jet printer head by processing a photosensitive glass by etching. In this method, a desired portion of the photosensitive glass is exposed to light from an ultraviolet lamp (exposure step), and the photosensitive glass is heated to 500 to 700 ° C. to crystallize the exposed portion (heat development step). This is a method of dissolving and removing the exposed portion with an etching solution (hydrofluoric acid solution) (etching step). Note that a high-pressure mercury lamp or the like is used as the ultraviolet lamp.

[0003]

In the conventional method, the control of the etching depth when etching a crystallized exposed portion formed on a photosensitive glass plate to form a groove or the like is performed by controlling the etching time or the etching solution. It has been performed under etching conditions such as temperature and concentration. However, the etching rate of the crystallized exposed portion fluctuates depending not only on the etching conditions but also on other factors such as exposure intensity and heat development conditions. Furthermore, since the etching rate changes due to fatigue of the etching solution, mixing of the photosensitive glass melted by the etching into the etching solution, and various effects such as how to hit the etching solution,
Controlling the etching depth was extremely difficult.

There is another problem that the surface roughness of the etched surface of the crystallized exposed portion is large. When used in an inkjet head, in the ink flow path on a surface with a large surface roughness, there is a problem that air bubbles mixed in the ink are stagnant, adversely affecting the ink ejection characteristics, and further, when used for micromachining, etc. Has a problem that the friction is large and the mechanical drive unit is difficult to move.

Further, it has been difficult to process a plurality of different etching depths by a single etching. Therefore, an object of the present invention is to make it easy to control the etching depth and to reduce the surface roughness of the etched surface when processing photosensitive glass, and to perform etching processing with different depths by one etching. Is to make it possible.

[0006]

In order to achieve the above object, a method for processing a photosensitive glass according to the present invention comprises the steps of:
An exposure step of exposing to a predetermined pattern by a laser , a heat development step of crystallizing the exposed part, and an etching step of removing the crystal part, by a processing method of forming a groove corresponding to the pattern in the photosensitive glass. And the above
Pal containing the photosensitive wavelength range of the photosensitive glass as a user
Used as the scan oscillation control type, the exposure step, the Le
Irradiating the photosensitive glass with multiple pulses
And by, characterized in providing a total exposure required to form the crystalline portion to a predetermined depth. Pulsed laser controlled, including the sensitivity wavelength range of sensitive <br/> light glass of the exposure means, XeCl excimer laser is preferable.

The above-described exposure step is performed at a plurality of positions on the surface of the photosensitive glass plate. If the total exposure amount differs depending on each position, it is suitable for processing grooves having different depths. It is.

The inventor of the present invention has proposed that, when exposing a photosensitive glass with an excimer laser and thermally developing the same, the etching rate is set to a minimum exposure amount that forms a crystal which is more susceptible to etching than an amorphous part. It has been found that a crystal which is susceptible to etching can be formed at a depth which does not penetrate the plate thickness even in a photosensitive glass having a small plate thickness.

The experimental data leading to this conclusion are shown in FIGS.
Is shown in FIG. 10 shows the transmittance and relative exposure sensitivity of the photosensitive glass. For example, 30 in the sensitivity wavelength range of the photosensitive glass
When a XeCl excimer laser having an emission wavelength of 8 nm is used, as shown in FIG. 10, the transmittance of the photosensitive glass is about 30% at a plate thickness of 1 mm. Therefore, the total exposure amount reaching the back surface of the photosensitive glass plate is 30% of the front surface. Therefore, the total exposure amount required to form a crystal part which is easily etched on the back surface does not reach.

[0010] Therefore, it is possible to form a crystal part which is easy to be etched by a predetermined depth by determining the exposure amount. As can be seen from FIG. 9, the energy intensity per pulse is 8
Exposed with XeCl excimer laser of 0 mJ / cm ^2, and the total exposure dose 160 mJ / cm ² and 320 mJ / cm ^2, using a hydrofluoric acid (HF) consists of a 6% solution liquid temperature 25 ° C. etchant Shower Etching with pressure 3kg / cm ²
As a result of examining the etching depth, the total exposure amount was 160 mJ / cm ^2.
Has an etching depth of about 1.0 mm and a total exposure of 320 mJ /
In cm ² , it can be seen that the etching depth changes to about 1.3 mm.

From this fact, it has been clarified that when the desired etching depth is determined, the total exposure amount to be irradiated is determined. Therefore, it is necessary to expose the film, and then perform thermal development and etching.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. Example 1 First, a method of manufacturing a flow path substrate of an inkjet printer head made of photosensitive glass by a processing method according to the present invention will be described in order of steps with reference to FIGS. As shown in FIG. 1, in a first step, a surface 10 a of a photosensitive glass plate 10 having a thickness of 2 mm is polished, a laser oscillator 1 is disposed above the photosensitive glass plate 10, and a laser 1 a is exposed to light through an exposure mask 2. Irradiate the surface 10a of the glass plate. The exposure mask 2 has exposure patterns (apertures) 2a, 2a corresponding to grooves to be formed on the surface of the photosensitive glass plate 10, and a light-shielding portion 2b at the other portion.

As the laser to be used, a pulse oscillation control type laser including a photosensitive glass having a sensitivity wavelength range of 150 to 400 nm is selected. In this example, a XeCl excimer laser having an oscillation wavelength of 308 nm was used. The energy intensity per pulse of the XeCl excimer laser at the time of this exposure was 80 mJ / cm ^2, and irradiation was performed for about two pulses to give a total exposure amount of about 160 mJ / cm ² . By this irradiation, exposed portions 11, 11 corresponding to the exposure pattern 2a are formed on the front surface 10a of the photosensitive glass plate 10. However, since the total exposure amount is small and equal, the exposed portions are formed up to the back surface 10b. It does not stop at a predetermined depth.

As shown in FIG. 2, the photosensitive glass plate 10 is heated to about 500 to 700 ° C., and is subjected to thermal development for crystallizing the exposed portion 11 to form a crystal portion 11a. Crystal part 1
Below 1a is an amorphous portion 11b.

Next, as shown in FIG. 3, a shower pressure of 3 kgf / h is applied to the photosensitive glass plate 10 using an etching solution in which a 6% solution of hydrofluoric acid (HF) is maintained at a temperature of 25 ° C.
Etching is performed in cm ² to dissolve and remove the crystal parts 11 a, thereby forming the grooves 12. As a result of this etching, as shown in FIG. 9, grooves 12 having the same depth of about 1.0 mm are formed, so that a flow path substrate of an ink jet printer head using these as ink flow paths is formed.

The ink jet printer head shown in FIG. 4 has a vibration plate 3 adhered to the surface of the photosensitive glass substrate formed as described above, and a piezoelectric element 4 provided at a predetermined position on the outer surface of the vibration plate. Things. In this ink jet printer head, ink is filled in an ink flow path 12 from an ink supply means (not shown), and when a voltage is applied to a piezoelectric element 4, the diaphragm 3 is deformed inward and the inside of the flow path is deformed. Is pressurized, the ink is ejected from the ink ejection port, and printing is performed.

Embodiment 2 Next, the embodiment shown in FIGS. 5 to 8 shows a method of forming a plurality of grooves having different depths on the surface of a photosensitive glass plate. As shown in FIG. 5, in the first exposure step, a plate thickness of 3 mm
The surface 20a of the photosensitive glass plate 20 is polished.
a through the exposure mask 5 to the surface 20a of the photosensitive glass plate.
Irradiation. The exposure mask 5 has an exposure pattern 5a in the form of a shallow groove formed on the surface of the photosensitive glass 20, and a light-shielding portion 5b in other portions.

The laser used is the same as in the first embodiment.
XeCl excimer laser with an oscillation wavelength of 8 nm
The energy intensity per pulse was 80 mJ / cm ^2, and irradiation was performed for about two pulses to give a total exposure amount of about 160 mJ / cm ² . By this irradiation, the surface 20a of the photosensitive glass plate 20
The exposed portion 21 corresponding to the exposure pattern 5a is formed, but since the total exposure amount is small, the exposed portion is not formed up to the back surface 20b, stops at a predetermined depth, and is not deeper than the predetermined depth. No exposed part is formed.

As shown in FIG. 6, in the second exposure step,
The laser 1a is applied to the surface 20a of the photosensitive glass plate via the exposure mask 6. The exposure mask 6 has an exposure pattern 6a in the form of a deep groove formed at another position on the surface of the photosensitive glass 20, and a light-shielding portion 6b at other portions. In this irradiation, the energy intensity per pulse of the laser 1a was set to 80 mJ / cm ^2, and irradiation was performed for about 4 pulses to give a total exposure amount of about 320 mJ / cm ² . By this irradiation, the surface 20a of the photosensitive glass plate 20
Although the exposure part 22 corresponding to the exposure pattern 6a is formed, since the total exposure amount is larger than in the case of the first exposure step,
The exposed portion is deeper than the depth of the exposed portion 21 but is not formed up to the back surface 20b, stops at a predetermined depth, and is not formed deeper than the predetermined depth.

As shown in FIG. 7, the photosensitive glass plate 20 is heated to about 500 to 700 ° C., and is subjected to thermal development for crystallizing the exposed portions 21 and 22 to form crystal portions 21a and 22a. Below these crystal parts 21a, 22a are non-crystal parts 21b, 22b.

Next, as shown in FIG. 8, the same etching as in the first embodiment is performed to dissolve and remove the crystal parts 21a and 22a to form grooves 23 and 24. As a result of this etching, as shown in FIG.
In the groove 24, the depth is about 1.3 mm, and a groove having a different depth is formed by one etching.

In each of the first and second embodiments, in the etching step, the amorphous portion below the crystal part 11a or 21a, 22a is slightly etched, but the etching rate is about 1/20 of the crystal part. Therefore, the total exposure amount may be determined in consideration of the etching depth in advance.

In the above embodiment, X is used as the exposure means.
Ecl excimer laser is used, but other lasers such as XeF (oscillation wavelength 351 nm), KrF
(Oscillation wavelength 248 nm), ArF (oscillation wavelength 193 nm) excimer laser or N ₂ laser (oscillation wavelength 337 nm)
A laser in which Nd ⁺ and YAG (yttrium aluminum garnet) are mixed,
Dye lasers, Kr ion laser, Ar ion laser or a copper vapor laser by <br/> physicians also fundamental oscillation wavelength light using a laser that is converted into the ultraviolet region by non-linear optical element.

[0024]

As described above, according to the present invention, in the present invention, Les
Pulse generator including the sensitive wavelength range of photosensitive glass
The vibration control type is used, and the exposure process uses the laser
By irradiating the photosensitive glass with a plurality of pulses,
Gives the total exposure required to form the crystal part to the specified depth
Time management is not required and total exposure
The amount can be easily controlled, and a crystal part easily susceptible to etching can be formed at a desired depth. Since an amorphous part appears by etching, the etched surface becomes smooth,
It is effective for processing ink channels and micro machines of ink jet printer heads. In addition , illumination of multiple pulses
By changing the total exposure amount of the exposure process by irradiation,
Grooves having different depths can be precisely formed by one etching, which facilitates processing.

[Brief description of the drawings]

FIG. 1 is a front view illustrating an exposure step according to a first embodiment of the present invention.

FIG. 2 is a front view of the photosensitive glass after a heat development step according to the first embodiment.

FIG. 3 is a cross-sectional view of the photosensitive glass after an etching step according to the first embodiment.

FIG. 4 is a cross-sectional view of an ink-jet printer head using a photosensitive glass substrate manufactured by the above method.

FIG. 5 is a front view showing a first exposure step in Embodiment 2 of the present invention.

FIG. 6 is a front view showing a second exposure step of the above.

FIG. 7 is a front view of the photosensitive glass after a heat development step of the above.

FIG. 8 is a cross-sectional view of the photosensitive glass after the above-described etching step.

FIG. 9 is a diagram illustrating a relationship between an etching time and an etching depth of a photosensitive glass.

FIG. 10 is a characteristic diagram showing transmittance and relative exposure sensitivity of a photosensitive glass.

[Explanation of symbols]

 1a Exposure means 10, 20 Photosensitive glass 11a, 21a, 22a Crystal part

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-232731 (JP, A) JP-A-5-139784 (JP, A)

Claims (3)

(57) [Claims] An exposure step of exposing the photosensitive glass to a predetermined pattern by a laser , a heat development step of crystallizing the exposed portion, and an etching step of removing the crystal portion.
A processing method for forming a groove corresponding to the pattern in the photosensitive glass, wherein the laser has a sensitivity wavelength range of the photosensitive glass.
In the exposure step, a plurality of pulses from the laser are applied to the sensing step.
By irradiating the optical glass, the crystal part
Method of processing a photosensitive glass is characterized in providing an overall exposure required to be formed in the. Wherein Oite to claim 1, said laser, X
A method for processing photosensitive glass, which is an eC1 excimer laser. 3. Oite to claim 1, said exposure step is intended to be performed for a plurality of positions of the photosensitive glass plate surface, the total exposure amount in each exposure step, wherein different respective Processing method of photosensitive glass.