JP2000202675A - Laser beam machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam machine capable of easily conducting the same machining to plural places of a work to be machined. SOLUTION: In a laser beam machine provided with a laser beam source, an optical system to irradiate a machining face of a work 30 to be machined with the laser beam oscillated from the laser beam source and a table to suck/ hold the work 30 as well as movable at least in the planar direction, a porous member 24 having plural holes communicating in the thickness direction and a suction means 28 to hold the work 30 placed on the surface of the porous member 24 from the end face of the porous member 24 are arranged above the table where the work 30 is placed, the work 30 is sucked/held through the holes of the porous member 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus using a laser beam, and more particularly to a laser processing apparatus using an excimer laser. The present invention relates to a laser processing apparatus for forming a through hole such as the above.

[0002]

2. Description of the Related Art Conventionally, when a workpiece such as a substrate is precision-processed on the order of μm, for example, when a hole is formed, the workpiece is processed by irradiating a laser beam such as an excimer laser. Laser processing machines are used.
In particular, a laser processing machine with high processing accuracy is generally used for a hole serving as a nozzle opening for discharging ink of an ink jet recording head since the processing state of the hole greatly affects ink characteristics.

In such a laser beam machine 100, FIG.
As shown in FIG. 1, a workpiece 110 is held on a chucking table 102 provided on an XYZ table 101 that can move in a three-dimensional direction. Further, as shown in FIG. 7, the chucking table 102
A plurality of suction holes 102a penetrating in the thickness direction are intermittently provided in a region where the substrate 10 is placed, and the workpiece 110 is moved through the suction holes 102a by, for example, a suction device 120 such as a vacuum. By being sucked, it is sucked and held on the surface of the chucking table 102.

Then, a laser beam L oscillated from a laser oscillator (not shown) is focused by an optical system 105 including a focusing lens 104 and the like held in a casing 103 and irradiated on the surface of a workpiece 110 to penetrate. A hole 111 is formed. Using such a processing machine, for example, when processing the nozzle openings in the nozzle plate constituting the ink jet recording head, generally, for example, using a polyimide sheet or the like having a thickness of about 50 μm, A tapered hole that gradually decreases from the laser light irradiation side surface to the back surface is formed.

In this case, since the diameter of the tapered hole, the angle of the taper, and the like need to be uniformed with high precision, the energy density, focus, and the like of the laser beam must be controlled with high precision.

[0006]

However, in the above-described laser beam machine 100, the workpiece 110 is held by sucking the workpiece 110 through the plurality of intermittently provided suction holes 102a as described above. The workpiece 1
A portion corresponding to the ten suction holes 102a;
Irregularities are formed between the portion between a and a. That is, the flatness of the surface of the workpiece 110 held on the chucking table 102 varies. Therefore, even if the focal position of the laser beam is adjusted with high accuracy at a predetermined position,
Since the substantial focal position of the laser beam with respect to the workpiece 110 at each processing position changes, there is a problem that the shape, size, and the like of the formed through-hole 105 vary. In order to solve this problem, it is necessary to readjust the focal position of the laser beam at each processing position, which increases the number of manufacturing steps.

Further, as described above, when forming the nozzle openings in the nozzle plate, this variation is directly
Since the ink ejection performance is greatly affected, it is desirable to form the ink as uniformly as possible. In view of such circumstances, an object of the present invention is to provide a laser processing apparatus capable of easily performing the same processing on a plurality of locations on a workpiece.

[0008]

According to a first aspect of the present invention, there is provided a laser light source, and an optical system for irradiating a laser light oscillated from the laser light source to a processing surface of a workpiece. And a table that holds the workpiece by suction and that can move at least in a plane direction. In the laser processing apparatus, an upper part of a region of the table on which the workpiece is placed is provided in a thickness direction. A laser processing apparatus comprising: a porous member that communicates air; and suction means for holding a workpiece placed on a surface of the porous member from an end surface of the porous member. .

A second aspect of the present invention is the laser processing apparatus according to the first aspect, wherein the porous member is made of a porous metal or a porous ceramic. According to a third aspect of the present invention, in the first or second aspect, the workpiece is a nozzle plate film constituting an ink jet recording head, and the nozzle irradiates the film with laser light to discharge ink. An opening is formed in a laser processing apparatus.

According to the present invention, there is provided a laser processing apparatus capable of holding a workpiece in a state in which the flatness of the surface thereof has a small variation and easily performing the same processing at a plurality of portions of the workpiece. it can.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments of the present invention. FIG. 1 is a schematic diagram of a laser processing machine according to one embodiment of the present invention. As shown in FIG. 1, a laser processing machine 10 according to the present embodiment is a device for forming a nozzle opening in a nozzle plate film 30 constituting an ink jet recording head, for example, a laser beam such as an excimer laser. A laser oscillator 11 for oscillating laser light, an optical system 12 arranged so that a laser beam oscillated from the laser oscillator 11 is irradiated perpendicularly to the surface of the workpiece 30, and a film 30 processed by the laser beam. And a holding movable part 13 that can move in three-dimensional directions.

The optical system 12 includes an attenuator 14, a homogenizer 15, a mask 16, and a wobble unit 17.
And a converging lens 19 held by a housing 18, which are sequentially arranged from the laser oscillator 11 side to the film 30. The laser light oscillated by the laser oscillator 11 is rectangular and has an energy distribution with a large energy density at the center, but the attenuator 14
This reduces the entire amount of laser light to an appropriate level, and the laser light after passing through the attenuator 14 has a similar energy distribution.

The homogenizer 15 is for homogenizing the energy distribution of the laser beam in the horizontal and vertical directions. For example, the homogenizer 15 homogenizes the energy distribution in the horizontal direction in the first stage, and homogenizes the energy distribution in the vertical direction in the second stage. Uniform energy distribution. The mask 16 is for cutting a rectangular laser beam into a predetermined size and shape, and has a predetermined size and shape, for example, as shown in FIG. A plurality of through-holes 16a having a diameter about three times as large as that of FIG.

The wobble unit 17 adjusts the energy distribution of the laser beam in the radial direction. As shown in FIG. 3, the wobble unit 17 is rotatably held with the translucent plate 21a inclined at a predetermined angle. I have. That is, after passing through such a wobble unit 17, the high-density region L ₁ in which the laser beam is always irradiated intermittently with low-density regions L ₂ occurs irradiated, the energy density in the radial direction of the laser beam L Differences occur. The rate of change of the energy density in the radial direction changes depending on the inclination angle of the transmissive plate 17a. For example, as shown in FIG.
If having a small inclination angle of 7a, the proportion is relatively large in the high-density region L ₁ of the central portion is small low-density regions L ₂ of the surrounding. On the other hand, as shown in FIG. 3 (b), when increasing the inclination angle of the plate 17a has a small proportion of high-density regions L ₁ of the central portion, the low-density region L ₂ of the surrounding
Is big. Thus, by changing the inclination angle of the plate 17a, it is possible to substantially adjust the average energy density of the entire laser beam L. Thereby, the energy density can be adjusted to an appropriate size.

For example, the film 30 is irradiated with laser light.
When a nozzle opening is formed, the taper angle of the through hole is usually changed by changing the energy density. For example, it is necessary to stabilize the energy density to about 1 J / cm ^2. The energy density of the laser light is not stable. However, by using the wobble unit as described above, the energy density of the laser beam can be substantially stabilized.

The focusing lens 1 held by the housing 18
Numeral 9 is for focusing the laser beam at a predetermined position. Note that the focusing lens 1 is actually provided inside the housing 18.
9, a plurality of lenses (not shown) are held, and the laser beam is focused at a predetermined position via the plurality of lenses. On the other hand, the holding movable section 13 includes a chucking table 20 for sucking and holding the film 30, and X, Y, and Z tables 21, 22, and 23 for moving the chucking table 20 in three-dimensional directions. Although not shown, these XYZ tables 21, 22, 23 are controlled by control means provided in the laser beam machine 10.

As shown in FIG. 4, the chucking table 20 of the present embodiment comprises a porous member 24 having a plurality of holes communicating in the thickness direction, and a holding member 25 for holding the porous member 24. The film 30 is placed on the porous member 24. The porous member 24 is not particularly limited as long as it has a plurality of holes for communicating air in a thickness direction and has a predetermined hardness.
It is made of porous metal or porous ceramics having countless air communication holes obtained by sintering metal or ceramics. Further, the size of the porous member 24 is preferably smaller than the film 30, and is most preferably substantially the same as the film 30.

On the other hand, the holding member 25 has, on one surface side, a concave portion 26 in which the porous member 24 can be fitted.
For example, a locking portion 26b for locking the porous member 24 over the entire circumference is provided on the periphery of the bottom surface 26a. In the present embodiment, the depth of the concave portion 26 to the locking portion 26b is substantially the same as the thickness of the porous member 24. Further, a communication hole 27 communicating with the outside is provided on the bottom surface 26a of the recess 26, and a suction device 28 such as a vacuum is connected to the outside of the communication hole 27.

The chucking table 20 of the present embodiment is obtained by fitting and holding the porous member 24 in the concave portion 26 of the holding member 25. At this time, the porous member 24 comes into contact with the locking portion 26b to be locked and held and fixed in the concave portion 26, and a predetermined space 29 is defined between the porous member 24 and the bottom surface 25a. . Further, since the depth of the concave portion 26 to the locking portion 26b is substantially the same as the thickness of the porous member 24, all the side surfaces of the porous member 24 are joined and sealed with the holding member 25, and the porous member 24 is sealed. The hole inside 24 is communicated only in the thickness direction.

Therefore, when the film 30 is placed on the chucking table 20 and the suction device 28 is driven, the film 30 is sucked through the communication hole 27, the space 29 and the hole of the porous member 24, and Is held by suction on the surface of the conductive member 24. Such a chucking table 2
In the case of 0, the film is sucked through the holes of the porous member 24, but since these holes are innumerable, the surface of the film corresponding to the holes and the surface of the film 30 corresponding to the other portions are different from each other. Accordingly, there is no displacement in the thickness direction, and the flatness of the surface of the film 30 is extremely high. Therefore, when the nozzle opening is formed in the film 30, once the focal position of the laser beam is adjusted with high precision, a uniform shape and size can be obtained at each processing portion without adjusting the focal position of the laser beam again at each processing position. Nozzle opening can be reliably formed.

It should be noted that such a laser processing apparatus is not limited to one that forms a nozzle opening, and it goes without saying that it can be used for any other processing.
Here, an example of a head chip using a nozzle plate formed using such an apparatus will be described. FIG. 6 is an exploded perspective view of the head chip according to one embodiment of the present invention.

As shown in FIG. 6, a plurality of grooves 52 are provided in the piezoelectric ceramic plate 51 in parallel, and each groove 52 is separated by a side wall 53. One end in the longitudinal direction of each groove 52 extends to one end surface of the piezoelectric ceramic plate 51, and the other end does not extend to the other end surface, but gradually decreases in depth. Further, electrodes 54 for applying a driving electric field are formed on the opening side surfaces of both side walls 53 in each groove 52 in the longitudinal direction.

Here, each groove 52 formed in the piezoelectric ceramic plate 51 is formed by, for example, a disk-shaped die cutter, and a portion whose depth is gradually reduced is formed by using the shape of the die cutter. Is done. In addition, each groove 5
The electrode 54 formed in 2 is formed by, for example, a known oblique evaporation. An ink chamber plate 55 is joined to the opening side of the groove 52 of the piezoelectric ceramic plate 51. In the ink chamber plate 55,
The ink chamber 56 has a recess communicating with the shallow other end of each groove 52, and an ink supply port 57 penetrating from the bottom of the ink chamber 56 in a direction opposite to the groove 52.

A nozzle plate 35 is joined to an end surface of the joined body of the piezoelectric ceramic plate 51 and the ink chamber plate 55 where the groove 52 is open, and the nozzle plate 35 is opposed to each groove 52 of the nozzle plate 35. Is formed with the nozzle opening 32 formed as described above. Further, the piezoelectric ceramic plate 51 and the ink chamber plate 5
Around the end of the joint 52 with which the groove 52 is open,
A nozzle support plate 58 is provided. The nozzle support plate 58 is joined to the outside of the end face of the joined body of the nozzle plate 35 to stably hold the nozzle plate 35.

[0025]

As described above, in the present invention, at least a part of the chucking table is constituted by a porous member having a plurality of holes communicating in the thickness direction. Also,
The workpiece was placed on the porous member, and the workpiece was suction-held through the holes of the porous member. As a result, the workpiece is held on the chucking table with a substantially uniform suction force in the surface direction, and the unevenness of the surface flatness is reduced. Therefore, when processing a through hole or the like in the workpiece, it is not necessary to correct the shift of the focal position of the laser light in each processing portion, and the focal position of the laser light with respect to the workpiece is always constant, and An object can be processed into a uniform shape and size.

Further, according to the present invention, a uniform nozzle opening can be formed in a film for each nozzle plate of an ink jet recording head, and an ink jet recording head having good ink discharge characteristics is surely provided. It has the effect that it can be done.

[Brief description of the drawings]

FIG. 1 is a schematic view of a laser processing machine according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a mask used in the laser beam machine according to the embodiment.

FIG. 3 is a schematic diagram illustrating a wobble unit used in the laser beam machine according to the embodiment.

FIG. 4 is a perspective view and a sectional view schematically showing a chucking plate according to the embodiment.

FIG. 5 is an exploded perspective view of a head chip according to one embodiment of the present invention.

FIG. 6 is a schematic view showing a main part of a laser beam machine according to the related art.

FIG. 7 is a schematic view showing a main part of a chucking plate according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Laser processing machine 11 Laser oscillator 12 Optical system 13 Holding movable part 14 Attenuator 15 Homogenizer 16 Mask 17 Wobble unit 18 Housing 19 Converging lens 20 Chucking table 21 X table 22 Y table 23 Z table

Continued on the front page F term (reference) 2C057 AF24 AF93 AP02 AP13 AP23 AP77 3C016 DA05 4E068 AF02 CE09

Claims (3)

[Claims] 1. A laser light source, an optical system for irradiating a laser beam oscillated from the laser light source to a processing surface of a workpiece, and a workpiece which is suction-held and movable at least in a plane direction. In a laser processing apparatus having a table, a porous member that communicates air in a thickness direction is provided above an area of the table on which the workpiece is mounted, and a porous member is formed from an end surface of the porous member. And a suction means for sucking and holding the workpiece placed on the surface of the elastic member. 2. The method according to claim 1, wherein the porous member comprises:
A laser processing apparatus comprising a porous metal or a porous ceramic. 3. The method according to claim 1, wherein the workpiece is a film for a nozzle plate constituting an ink jet recording head, and the film is formed with a nozzle opening for irradiating a laser beam to discharge ink. A laser processing apparatus characterized by the above-mentioned.