JP2002033539A - Drilling apparatus for green sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for fast precision drilling and for free alignment of drilling with no use of a mask in green sheet working which uses laser. SOLUTION: There are provided an LD excitation laser oscillator 1, a field lens 2, an imaging lens 4, and an XY table 9. A green sheet 5, which is to be worked, is placed as an XY table. The laser oscillated from a laser rod of the oscillator 1 is end-surface focused on the green sheet on the XY table through the field lens 2 and the imaging lens 4, so that a given shape is projected on the green sheet for drilling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for boring a ceramic green sheet and a processing apparatus using a laser. In particular, the present invention relates to a method for providing a means for improving the quality at the time of drilling, that is, the accuracy of the drilling speed and the hole shape, and for providing these techniques at low cost.

[0002]

2. Description of the Related Art A green sheet is a very soft sheet in a raw sheet state before ceramic sintering. In recent years, inductors and capacitors have been laminated for miniaturization and high capacity, and each layer is electrically connected via a hole. This piercing is performed by using a raw sheet (green sheet) before sintering because the ceramic is hard after sintering and it becomes very difficult to pierce. When the hole diameter for interlayer bonding is 150 μm or less, laser processing is used. In the case of green sheets, initially CO2 lasers were mainly used. However, when the hole diameter becomes φ50μm or less, C
O2 lasers have a long wavelength, which exceeds the limit of light-gathering ability. Therefore, recently, for ferrite-based green sheets that have an absorption band even in the near infrared region, Nd:
YAG lasers are beginning to be used.

A YAG laser has an oscillation wavelength of 1.064 μm,
Since a brown ferrite sheet has strong absorption, good processing can be performed with an imaging optical system having a configuration as shown in FIG. In the figure, the aperture of the mask is transferred onto the green sheet at the reduction magnification indicated by the imaging magnification M = b / a.
For example, assuming that the hole diameter of the mask is φ0.5 mm, when M = 1/10, a hole with a diameter of φ50 μm will be formed. If a high-precision XY stage is used in this imaging method, the processing position accuracy will be 5 to 10 μm. Regarding the drilling speed, laser oscillation is limited to operation up to about 200 pps. Therefore, drilling one hole at a time with one shot of a laser pulse is also inefficient and cannot meet the drilling speed of 1,000 holes / second required in recent years. Therefore, as shown in FIG. 14, a plurality of holes are formed in the mask, and a sufficiently large laser pulse energy is applied to all the holes to form a uniform image. Can be improved to seconds. High-speed YAG laser machines using this principle have become widespread.

[0004]

In the above-mentioned conventional processing method, a laser-excited multi-mode pulse laser is used as a laser light source, so that the transverse mode is unstable, so that the laser beam distribution is poor, and the laser beam distribution is poor. Aperture
Since the laser intensity applied to the hole also fluctuates greatly, there has been a problem that the size of the hole diameter and the shape of the hole become unstable.
In addition, the power actually used for drilling on the green sheet is several percent of the total power applied to the mask.
-5%, and the efficiency of using laser power is low, and the mounting of a high-power laser for improving accuracy increases the cost of the entire apparatus. Further, there are also problems such as necessity of a heat treatment problem in the mask and severe consumption of the mask.

An object of the present invention is to provide a green sheet drilling apparatus capable of processing both the hole shape and the drilling position with high precision, and reducing the cost of the apparatus itself and its operation. I do.

[0006]

To achieve the above object, the present invention provides a green sheet drilling apparatus comprising a plurality of laser diodes (LD) pumping type laser oscillators which can be adjusted independently. At most φ
It is characterized by processing a plurality of holes in the green sheet through an optical system that irradiates an input beam onto a small-diameter rod of about 3 mm and forms an image directly on the output side end surface of the green sheet without using a mask. And

The first invention of the present application comprises a solid-state pulse laser oscillator having a small-diameter laser rod, a table on which a field lens, an imaging lens, and a green sheet are mounted, and a laser pulse width of 1 μs to 200 μs. A green sheet is directly illuminated with a predetermined shape on the green sheet by an emission laser set in the green sheet. According to the present invention, there is no need to create a mask used in conventional laser processing. In this respect, the present invention differs from the prior art.

The second invention of the present application comprises a pulsed solid-state laser oscillator of the LD excitation type having a small-diameter laser rod, a field lens, an imaging lens, and a table on which a green sheet is mounted. A green sheet drilling apparatus characterized by directly irradiating a predetermined shape with a laser. According to the present invention, there is no need to create a mask used in conventional laser processing.

The third invention of the present application is directed to a green sheet drilling apparatus according to claim 1 or 2,
An adjusting means for adjusting the position of the laser oscillator is provided. According to the third invention of the present application, by adjusting the position of the laser oscillator, there is an advantage that the shape of the hole formed by forming an image on the green sheet can be adjusted.

The fourth invention of the present application is directed to a green sheet drilling apparatus according to claim 1 or 2,
A total reflection mirror is provided between the field lens and the imaging lens. According to the fourth invention of the present application, by adjusting the angle of the reflection mirror, the installation positions of the laser oscillator and the green sheet can be freely adjusted.

In a fifth aspect of the present invention, in the green sheet drilling apparatus according to the fourth aspect, there is provided a means for observing a laser leakage from a total reflection mirror. Specifically, a laser power monitor having a function of monitoring light leaking from the total reflection mirror is provided at a position facing the laser oscillator via the total reflection mirror. As a result, the laser power value applied to the green sheet is relatively monitored, so that the laser power can be properly managed during laser drilling. Therefore, according to the fifth invention of the present application, since the laser power corresponding to each of the holes processed by one LD laser can be detected independently, variation in the hole diameter can be prevented, and the hole of each hole can be prevented. The diameter can be controlled to a stable size.

According to a sixth aspect of the present invention, there is provided a green sheet drilling apparatus according to the first or second aspect,
It is characterized by having a means for optically observing laser processing on the green sheet. According to the sixth invention of the present application, it is possible to observe the shape, size, or position of the hole formed in the green sheet.

According to a seventh aspect of the present invention, there is provided a green sheet drilling apparatus according to claim 1 or 2,
The coupling means in the laser oscillator comprises an optical fiber having a pair of coupling lenses at both ends. According to the seventh invention of the present application, it is possible to freely set the positions of the laser oscillator in the laser oscillator and the laser rod of the emission unit.

According to an eighth aspect of the present invention, in the green sheet drilling apparatus according to the first or second aspect, the shape of the coupling means in the laser oscillator is larger than the entrance to which the laser diode excitation light is incident. Is characterized in that its diameter is reduced. According to the eighth invention of the present application, when the oscillated laser is made incident on the emission rod, it is possible to concentrate the laser on the central portion of the rod.

According to a ninth aspect of the present invention, in the apparatus for drilling a green sheet according to claim 1 or 2, the laser rod emission port in the laser oscillator is provided with a coat through which almost 100% of laser diode excitation light is transmitted. The laser rod is characterized by comprising a partial region including a central portion of the laser rod, and another region to which a total reflection mirror coat is applied.
According to the eighth invention of the present application, since the beam diameter of the laser emission light can be made smaller than the laser rod diameter, the emission end face of the laser rod can be imaged to a smaller diameter. Here, it is desirable that a part of the region including the central portion of the laser rod coated with almost 100% transmission is a region of 1/2 or 1/3 of the rod diameter. It is even more desirable that they form a substantially perfect circle.

According to a tenth aspect of the present invention, in the green sheet drilling apparatus of the first or second aspect, a nonlinear crystal is arranged between the laser oscillator and the field lens. According to the tenth aspect of the present application, it is possible to convert the wavelength of the oscillated laser. As a result, it is possible to form a hole in a green sheet, which has conventionally been difficult to process.

The eleventh invention of the present application is characterized in that, in the green sheet drilling apparatus according to claim 1 or 2, a plurality of laser oscillators are arranged. According to the eleventh invention of the present application, since a simultaneous laser can be emitted from a plurality of laser rods and processing can be performed, it is possible to increase the processing speed for drilling a green sheet.

According to a twelfth aspect of the present invention, in the green sheet drilling apparatus according to the eleventh aspect, an adjusting means having a function of independently controlling the operations of the plurality of laser oscillators is provided. According to the twelfth invention of the present application,
A more complex drilling pattern can be applied to the green sheet than when a plurality of laser oscillators are simply emitted simultaneously.

According to a thirteenth aspect of the present invention, in the green sheet drilling apparatus according to the first or second aspect, an adjusting means for adjusting a position of a table on which the green sheet is placed is provided. And This makes it possible to adjust the position of the hole by adjusting the position of the green sheet according to the position where the laser image is formed.

According to the fourteenth invention of the present application, claim 5
The apparatus for drilling a green sheet according to any one of the preceding claims, further comprising adjusting means for analyzing an optical observation result of the green sheet and adjusting a position of the laser oscillator. This makes it possible to automatically adjust the laser oscillator with reference to the hole processed on the green sheet.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment) FIG. 1 is a structural view of a processing apparatus according to the present invention, FIG. 2 is a view showing a detailed internal form of a laser oscillator and a rod, and FIG. FIG. 3 is a principle diagram of an optical system that directly forms an image on an output side end surface on a green sheet.

In FIG. 1, 1 is an LD pump laser oscillator, 2 is a feed lens, 3 is a mirror, 4 is an imaging lens, 5 is a green sheet, and 6 is a fine movement stage. 7
Indicates an observation optical system, 7-1 is a CCD camera, and 7-2 is a relay lens. 8 is a power monitor and 9 is an XY stage.

The LD excitation lasers emitted from a plurality of LD excitation laser heads 1 (four in the first embodiment) pass through a long focal point feed lens 2 and are reflected by a mirror 3. The light leaked from the mirror is observed by the power monitor 8.
The power monitor 8 is provided for the purpose of relatively monitoring the laser power value applied to the green sheet in order to prevent variations in the diameter of the laser drilling hole. That is, the laser power corresponding to each hole processed by one LD laser can be appropriately managed based on the amount of leaked light detected by the power monitor 8. The reflected light is condensed at the front focus of the imaging lens 4 and is incident. The focus is adjusted by finely adjusting the laser head in the optical axis direction using the stage 6. Here, the main imaging lens 4
After passing through, the (pseudo) telecentric optical system is configured as shown in FIG. 2, so that the green sheet 5 can be irradiated with laser light almost vertically. The hole on the green sheet processed by laser irradiation is the observation optical system 7
The position can be adjusted by the XY stage 9 as needed, and can be adjusted so that a hole is formed at an appropriate position on the green sheet.

As described above, the laser light is oscillated by the laser rod inside the LD laser head 1, which forms the optical system shown in FIG. 2 and is directly connected to the green sheet without requiring a mask. The image has been realized. FIG. 2 is an explanatory diagram of the optical system of the LD excitation section according to the first embodiment.

In FIG. 2, 100 is a YAG rod, 2 is a field lens, 3 is a total reflection mirror, 4 is an imaging lens, and 5 is a green sheet.

The laser light oscillated from the YAG rod 100 is YAG
When the light exits from the exit end face of the rod, it passes through the field lens 2 and is reflected by the total reflection mirror 3 and is focused near the front focal point of the imaging lens 4. Thereafter, the light that has passed through the imaging lens 4 is irradiated vertically on the green sheet 5. At this time, on the surface of the green sheet 5, an image is formed at a reduction ratio of approximately M = a / A. Assuming that the diameter of the YAG rod is φ2 mm and the imaging magnification is M = 1/20, φ1
Irradiation can be performed at 00 μm. FIG. 3 shows a case where two laser heads are used. However, in actuality, as shown in FIG. 1, the system is configured to increase the number to about 4 to 8 and to process about 4 to 8 holes simultaneously. Each laser head is independently a stage that can be finely moved in the X, Y, and Z directions, and can be adjusted with a precision of 10 μm. Since these movement mechanisms are controlled so that the fluctuation of the environmental temperature is controlled to ± 0.5 ° C., it is possible to perform the control in consideration of the change due to the thermal expansion.

In order to realize the optical system as shown in FIG. 2, it is necessary to devise an LD-excited laser through a small-diameter rod so as to form an image on the end face of the rod.
FIG. 3 shows a detailed configuration diagram of such a laser rod.

FIG. 3 shows a detailed configuration of the LD pumped laser head in FIG. In FIG. 2, 100 denotes an Nd: YAG rod, 100-1 denotes a partially transmitting mirror coat, and 100-2 denotes a total reflection mirror coat. 101 is a heat sink for cooling, 102
Denotes a high thermal conductive material, 103 denotes a coupling lens, 104 denotes a laser diode (LD), and 105 denotes a housing case.

The laser oscillation head includes a laser oscillator and a laser rod. In laser oscillators,
The configuration is such that the excitation laser light emitted from the LD 104 is introduced into the YAG rod 100 via the coupling lens without loss. Although a green lens is used as the coupling lens in FIG. 3, it is also possible to configure a combination of various lenses described later as another embodiment. The temperature of the LD 104 is controlled to be constant by using a Peltier element 105. Although not shown in the drawing, the other side of the Peltier element is made of constant-temperature cooling water used for the cooling heat sink 101, and the laser head is designed to be as small as possible. The laser light oscillated from the laser oscillator enters through the coupling lens 103 and is incident on the YAG rod.
Incident at 100.

In this laser rod portion, a partially transmitting mirror coat 100-1 and a total reflection mirror coat 100-2 are mounted on both end surfaces of the rod, respectively, and constitute a resonator. This mechanism functions as a laser resonator, and laser alignment is not broken, so that the long-term stability of the laser is improved. In order to form an image of the rod end surface of the laser beam via the YAG rod 100, the rod end is projected from the end surface of the cooling heat sink 101 by about several mm. At this time, the coat of the 100-2 part is totally reflected at 1064 nm by the dichroic mirror and also serves as the 908 nm AR coat. 908 nm is the LD oscillation wavelength of the YAG laser. Laser rod up to 30mJ /
The rod side surface is cooled by a cooling heat sink 101 at a constant temperature that does not cause dew condensation in order to enable excitation light input of pulse and 500 pps. Although FIG. 2 shows an example in which the cooling water passage 101-1 is provided and water-cooled, the cooling can be actually performed by an electronic cooling unit such as a Peltier element. Indium (metal) is used as the high thermal conductive material 102 to reduce the thermal resistance between the YAG rod and the heat sink 101 for cooling.

(Other Embodiments) In the green sheet drilling apparatus according to the present invention, in addition to the above-described embodiment, each component part is changed according to the situation and the type of green sheet to be processed within the scope of the gist. By changing or improving, it becomes possible to improve the processing accuracy and to perform processing that was difficult in the past.

The coupling means of the laser oscillating section may be made of any shape or material other than the coupling lens as long as it can be incident on the laser rod without impairing the frequency and intensity of the incident laser. The changes used are also possible. For example, the coupling lens of the laser oscillator shown in FIG.
103 is an optical fiber 9 provided with coupling lenses 10 at both ends as shown in FIG. 4, so that the laser light can be guided flexibly and the apparatus configuration can be given a degree of freedom. In the configuration of this patent, the reduction of the pitch interval of the laser head is also an important design factor, but by incorporating a coupling lens using this optical fiber, a composite laser head portion with a reduced pitch interval can be constructed. .

Further, the coupling lens 103 in FIG. 3 may be formed into a tapered rod 11 as shown in FIG. 5, and the excitation laser light may be introduced into the YAG rod 100. Thereby, even when the excited laser is largely leaked when entering the rod via the coupling lens, the laser can be concentrated at the center of the rod, and efficient excitation laser incidence becomes possible. Here, the ratio of the diameter of the entrance end to the diameter of the exit end of the tapered rod is about 2: 1.
AR coating is applied to 1064 nm. The diameter of the exit end should be 90% or less of 100 YAG rod diameter.

Further, the YA of the LD pumped laser oscillator shown in FIG.
The coating on the emission end face of the G rod may be divided into two types of dielectric multilayer films. In FIG. 6, an AR coat 100-4 (partial reflection coat) is applied to the central part of the output end face of the YAG rod for 1064 nm, and a mirror coat for totally reflecting 1064 nm is attached to the remaining outer peripheral part. A dichroic mirror 100-2 (1064 nm total reflection coat / 809 nm AR coat) is attached to the other rod (incident) end face. By applying an output mirror coat with a diameter smaller than the laser rod diameter,
Even if a φ3.0 mm laser rod is used, the diameter of the actual laser output can be easily reduced to about φ1.0 mm to 2.0 mm. As a result, a hole diameter of Φ50 μm to 100 μm can be easily realized on the green sheet. In practice, it is practically difficult to directly use a laser rod of φ2.0 mm or less, so this method is a very effective means when drilling holes near φ50 μm.

Further, a non-linear crystal can be arranged at the tip of the laser rod of the LD-pumped laser oscillator shown in FIG. 3 as shown in FIG. As a nonlinear crystal, for example, KT
High conversion efficiency for P, LBO, BBO, CLBO, etc.
It is desirable to use one having excellent crystal stability. In this case, use a thin crystal of about 0.5 to 3.0 mm and bring it into contact with the laser rod emission end face. In this case, Nd: Y
Since almost no converted light can be obtained by irradiating an AG laser beam to a nonlinear crystal, Nd: YL having a fundamental wavelength of 1053 nm is used.
Use F laser. Therefore, Nd:
Oscillate with polarized light using a YLF rod. Although not shown in the figure, a constant temperature cooling mechanism for keeping the crystal temperature constant is attached around the nonlinear crystal to keep the conversion efficiency constant. As a result, with regard to white green sheets (alumina ceramics), which have been increasing in demand recently, even if the processability is poor at a YAG laser wavelength of 1064 nm, the second harmonic (SHG) 532 nm and the third harmonic (THG ) Can be expected to improve workability by mixing ultraviolet light (UV light).

In addition, a plurality of LD pumped laser heads
By forming a LD laser head section by arranging in a matrix of rows x N columns and by adding a function for controlling each operation to an XY stage or the like, complicated drilling becomes possible, Accuracy can be improved.

FIG. 7 shows a mechanism for independently controlling eight LD pumped laser heads arranged in 4 rows × 2 columns. In the figure, 1 denotes an LD pump laser head unit, 200 denotes an LD driver unit, 201 denotes a decoder, 202 denotes a PIO, and 203 denotes a control computer (PC). LD driver 200 with control PC installed independently for each laser head
By controlling the laser beam, each laser head can emit laser independently and synchronously with the operation of the XY stage. Therefore, in addition to the repetitive patterns such as the drilling examples 1) and 2) shown in FIG. 9, the processing in the case where the drilling pattern has no periodicity, which is impossible with the processing using the conventional mask. Also becomes possible.

Further, as shown in FIG. 10, a linear scale 12 is provided on an XY table for processing a green sheet, which is connected to an XY stage controller 13, and further controlled by the control PC 203. Thus, it is possible to constantly recognize the exact position of the stage. Drilling can be controlled in synchronization with this and the oscillation of each laser rod, so that the drilling pattern can be further complicated.
For example, if the LD pump laser heads are arranged in one or more rows in the processing direction, the signal from the linear scale of the XY stage gives the delay time set only to the specific LD pump laser head, so that the hole position can be adjusted. Can be shifted as set. FIG. 11 shows an example of a drilling pattern when a delay time is provided. The drilling position can be shifted by giving a specific laser head a delay time τ [sec] obtained by a distance X [mm] = Vconst × τ to be shifted. However, in this case, it is assumed that the XY stage is moving at a constant speed Vconst [mm / sec]. If the current control system is used, the drilling position accuracy at this time will be about ± several μm, and the change of the hole position can be easily controlled by this method.

Further, it is also possible to observe the drilling position and shape in real time, and synchronize this with the control of the laser head irradiation time interval and the stage position. FIG.
, 10 is an image processing device, 7 is an observation optical system, 1
Reference numeral 1 denotes an XYZ linear translator. Image processing device
According to 10, the hole diameter of the hole processed on the green sheet and the interval between each hole are measured by image processing. For image processing, a resolution of about 1/20 of the minimum drilled hole diameter is used as the minimum resolution. The state of drilling is determined by the control PC 203 through image processing, and the position of the laser head is finely adjusted with an accuracy of about 10 μm by the interlocking XYZ linear translator 11.

Lastly, in the embodiment of the present invention, only two types of laser media, Nd: YAG and Nd: YLF, are shown, but those belonging to Nd: YVO4, Nd: YAP, and Nd: YAIO are also the same. It is effective for In addition, an Nd: YAB laser capable of directly oscillating visible light (SHG) can be applied.

[0041]

As is clear from the above description, according to the present invention, the pulse width and intensity suitable for the green sheet to be processed can be selected by converting the laser excitation mechanism from lamp excitation to LD excitation. Therefore, laser oscillation with high energy efficiency and high stability can be achieved. in addition,
Since an optical system that does not project a mask used in the related art is used, the laser output can be reduced by almost two digits, so that the stability is improved and the drilling accuracy is improved. At the same time, the laser utilization efficiency becomes almost 100%, and the size and cost of the drilling device can be reduced.

Since the LD-excited laser oscillator according to the present invention also requires low oscillation intensity during processing, it is possible to reduce the size of one laser head. In particular, since the laser in this patent is of the end face type, it is possible to reduce the size and make the laser head smaller than φ10 mm as shown in FIG. It is possible to form a laser head unit in which a plurality of these are combined and arranged in M columns × N rows. Lasers oscillated from the respective laser heads form a pseudo-telecentric optical system via a field lens and a coupling lens, and vertically enter the green sheet on the XY stage from the imaging lens. This allows the laser head to:
A hole corresponding to the hole drilled by 1 and having high hole shape accuracy can be obtained. By controlling the position and irradiation timing of each LD excitation laser head using a control system, it is possible to form an arbitrary hole pattern on a green sheet, which was difficult with an optical system using a conventional mask.

Assuming that the imaging ratio at the time of processing is 1 / M,
If a mechanism to adjust the position of each LD pumped laser head with 10 μm accuracy is provided, 10 μm / M
Can be adjusted with a precision of. For example, if M = 10, then 1
Fine adjustment with μm accuracy is possible. The hole diameter can also be controlled by adjusting the fine movement stage 6 shown in the first embodiment of FIG. 1 in the optical axis direction (Z-axis direction). In the conventional machining process, after looking at the machining results,
The hole diameter and the hole interval formed in the mask are adjusted, but in comparison with this, the present invention also has the effect of greatly saving time and mask cost in green sheet processing technology.

Further, by using an LD-pumped laser oscillator, the laser pulse width can be reduced from 1 μs to 200 μs.
It has become possible to continuously vary the width of s. With the conventional laser, the shape of the processed hole becomes explosive, it is not a perfect circle, it is distorted, and the material and thickness have been optimized for the drilling of white alumina-based green sheets that could not be processed with good quality. There is also an effect that the pulse width can be selected, and a drilling technology of φ100 μm or less having an excellent shape can be provided.

[0045]

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a green sheet drilling apparatus of the present invention.

FIG. 2 is a diagram showing an image forming optical system in an embodiment.

FIG. 3 is a diagram showing details of an LD oscillation laser head unit in FIG. 1;

FIG. 4 is a diagram showing details of an LD oscillation laser head unit when an optical fiber is used.

FIG. 5 is a diagram showing details of an LD oscillation laser head unit when a tapered rod is used.

FIG. 6 is a diagram showing details when two types of dielectric multilayer films are mounted on the tip of a laser rod of a laser head unit.

FIG. 7 is a diagram showing details when a nonlinear crystal is mounted on the tip of the laser rod of the laser head.

FIG. 8 is a schematic configuration diagram of an LD laser head unit in which a plurality of LD excitation laser heads are arranged in M rows × N columns.

FIG. 9 shows an example of drilling processing using the LD pumped laser head shown in FIG. 8;

FIG. 10 is a schematic configuration diagram of an XY stage equipped with a linear scale and a control mechanism of a laser head unit shown in FIG. 8;

FIG. 11 shows an example of drilling when the control mechanism shown in FIG. 10 is used.

FIG. 12 is an observation optical system equipped with an image processing device and XYZ.
Schematic configuration diagram of a green sheet drilling apparatus of the present invention equipped with a laser head equipped with a linear translator and these control devices

FIG. 13 shows an image forming optical system used for a conventional green sheet drilling process.

FIG. 14 is a diagram showing a correlation between a laser irradiation range and a hole shape of a mask in an imaging optical system using a conventional mask.

[Explanation of symbols]

 1. LD excitation laser head, 2. Field lens 3. Total reflection mirror 4. Imaging lens 5. Green sheet 6. Fine movement stage 7-1. CCD camera 7-2. Relay lens 8. Power monitor 9. XY stage 10 .Image processing device 11.XYZ linear translator 12.Linear scale 13.XY stage controller 100.YAG rod 100-1.Partial transmission mirror coat 100-2.Total reflection mirror coat 100-3.Total reflection mirror coat 100-4. AR coating (partial reflection mirror coating) 100-5. YLF laser rod 101. Cooling heat sink 101-1. Cooling water channel 102. Indium 103. Coupling lens 104. Laser diode (LD) 105. Casing case 106. Peltier element 200 .LD driver 201.Recorder 202.PIO 203.PC (Personal Computer) 210. nonlinear crystal 500. copper mask 501. The laser irradiation region 502. Mask holes (four holes)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01S 3/07 B23K 101: 42 // B23K 101: 42 H01S 3/094 S

Claims (14)

[Claims] A solid-state pulse laser oscillator including at least a laser diode, a small-diameter laser rod, and coupling means for condensing laser light emitted from the laser diode into the small-diameter laser rod; and a field lens. It consists of an image lens and a table on which the green sheet is placed,
A green sheet drilling apparatus, which irradiates an emitted laser having a laser pulse width of 1 μs to 200 μs directly onto a green sheet in a predetermined shape. 2. An LD-excited pulsed solid-state laser oscillator having a small-diameter laser rod, a field lens, an imaging lens, and a table on which a green sheet is mounted. A green sheet drilling device characterized by irradiation. 3. The green sheet drilling apparatus according to claim 1, further comprising adjusting means for adjusting a position of the laser oscillator. 4. The green sheet drilling apparatus according to claim 1, further comprising a total reflection mirror between the field lens and the imaging lens. 5. The green sheet drilling apparatus according to claim 4, further comprising means for observing laser leakage from the total reflection mirror. 6. The green sheet drilling apparatus according to claim 1, further comprising means for optically observing laser processing on the green sheet. 7. The green sheet drilling apparatus according to claim 1, wherein the coupling means in the laser oscillator comprises an optical fiber having a pair of coupling lenses at both ends. apparatus. 8. The apparatus for drilling a green sheet according to claim 1, wherein the shape of the coupling means in the laser oscillator is smaller than the diameter of the entrance to which the laser diode excitation light is incident. A green sheet drilling device. 9. An apparatus for drilling a green sheet according to claim 1, wherein the laser rod emission port in the laser oscillator receives almost 100% of the laser diode excitation light.
A green sheet drilling device, comprising: a part of a region including a central portion of a laser rod coated with a light-transmitting coating; and another region coated with a total reflection mirror. 10. The green sheet drilling apparatus according to claim 1, wherein a nonlinear crystal is arranged between the laser oscillator and the field lens. 11. The green sheet drilling apparatus according to claim 1, wherein two or more laser oscillators are arranged. 12. The green sheet drilling apparatus according to claim 10, further comprising adjusting means having a function of independently controlling the operations of the plurality of laser oscillators. 13. The green sheet drilling apparatus according to claim 1, further comprising adjusting means for adjusting a position of a table on which the green sheet is placed. 14. A green sheet drilling apparatus according to claim 5, further comprising adjusting means for analyzing the optical observation result of the green sheet and adjusting the position of the laser oscillator. .