JPH0412602B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a laser processing device, and particularly to a laser trimming device that can perform laser trimming with high efficiency.

[Background of the invention]

2. Description of the Related Art Conventionally, there has been known a laser trimming device as shown in FIG. 1, which adjusts the resistance value by forming grooves on a resistor printed on a substrate using a laser beam. That is, 1 is a laser oscillator, which is equipped with a Q switch 2 to obtain a single pulse having a narrow pulse width and a large peak value. A reflecting mirror 4 tilted at 45 degrees so as to irradiate the workpiece 6 on the main body station 7 placed perpendicularly to the laser oscillator 1 with the laser beam 3 from the laser oscillator 1
is placed on the optical path. The laser beam 3 reflected by the reflecting mirror 4 enters the scan optical section 5, where it is focused and scanned so as to match the processing position of the workpiece 6. The measurement control section 9 controls oscillation and stopping of the laser oscillator 1, scanning of the laser beam by the scan optical section 5, measurement of the resistance value of the workpiece 6, and the like. Note that 8 is a control line.

Functional trimming using such a laser trimmer device operates the circuit of a thick film module, which is a product to be laser processed, to bring the circuit characteristics into line with desired target values.

However, in actual trimming, the time it takes for the circuit to stabilize after circuit switching and the measurement time after trimming take up a large proportion of the time, accounting for more than half of the total working time. For this reason, the laser oscillation time of the trimmer device is short.
Laser oscillation efficiency was extremely low.

The processing status of such a conventional laser trimming device is shown in a timing chart as shown in FIG. Note that the horizontal axis represents the passage of time, and the vertical axis represents the amount of laser light irradiation. Therefore, as is clear from this figure, the rectangular area where the trimming process is actually performed is extremely small.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a laser trimming device that increases the oscillation efficiency of a laser and thus enables efficient laser trimming work.

[Summary of the invention]

In order to achieve the above object, in the present invention,
The laser beam oscillated from the laser oscillator is received by a deflector, and the deflector deflects it to take multiple optical paths.The scan optical section and workpiece are placed on each optical path to focus and scan the laser beam. The present invention provides a laser trimming device in which a laser oscillator, a deflector, a scan optical section, and a station section are arranged, and a measurement control section controls the laser oscillator, deflector, scanning optical section, and station section.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Note that the same parts in the drawings are given the same reference numerals. FIG. 2 is a configuration diagram showing an example of a laser trimming device according to the present invention.

Reference numeral 1 denotes a laser oscillator, which is equipped with a Q switch 2 to obtain a single pulsed laser beam having a narrow pulse width and a large peak value. As a method for the Q switch 2, for example, an electro-optical element is placed in a resonator, and the direction of polarization is controlled by applying a voltage from the outside.
Laser light 3 irradiated from laser oscillator 1 is incident on deflector 10 . The deflector 10 switches and deflects the laser beam 3 so that it can take a plurality of optical paths. In this embodiment, two optical paths are selected. First, the laser beam 31 passing through the first optical path is bent at a right angle by a reflecting mirror 41 arranged on the optical path at an angle of 45 degrees. This is because the resistor 61, which is the workpiece, is placed in a direction perpendicular to the laser oscillator 1. The laser beam 31 whose optical path is bent by the reflecting mirror 41 enters a scan optical section 51 disposed in front of the optical path. The scan optical section 51 is for condensing and further scanning the laser beam 31 so as to be suitable for trimming work. The workpiece is placed at a position where this focused laser light 31 is optimally irradiated. The laser beam 31 is then scanned by the scan optical section 51 to form a desired groove on the resistor 61 printed on the substrate 71. During this trimming process,
The resistance value of the resistor 61 is successively measured by the measurement control section 9, and the scanning of the scan optical section 51 is similarly controlled by the measurement control section 9 according to the data. 8 is a control line.

Next, a case will be described in which the laser beam 3 is deflected to the second optical path by the deflector 10.

The laser beam 32 whose optical path is deflected by the deflector 10 passes through two reflecting mirrors 4 arranged on the optical path.
2,43 at right angles. The inclination of the first reflecting mirror 42 is set so that the laser beam travels parallel to the direction in which it is irradiated from the laser oscillator 1, and the second reflecting mirror 43 is provided at an angle of 45°. The laser beam 32 is bent at a right angle. Similar to the case where the laser beam 31 travels along the first optical path, the laser beam 32 whose optical path is bent by the reflecting mirrors 42 and 43 passes through the scan optical section 52 disposed in front of the optical path.
incident on . The laser beam 32 is transmitted to the scan optical section 52
The light is focused and scanned. This scan optical section 5
2 may be the same as 51. A resistor 62, which is a workpiece, is placed at a position where this focused laser light 32 is optimally irradiated. And laser beam 3
2 is scanned by the scan optical section 52 to form a desired groove on the resistor 62 printed on the substrate 72. As in the case of the first optical path, control of the scan optical section 52, oscillation/stop control of the laser oscillator 1, and measurement of the resistance value of the resistor 62 are performed by the measurement control section 9, respectively.

Trimming processing using the laser trimming device configured as described above is performed as follows. First, the measurement control unit 9 positions the resistor 61 to be processed as desired, and then the focusing and scanning of the scan optical unit 51 is checked in accordance with the processing position. Next, the measurement control unit 9 controls the deflector 10
is controlled to be deflected to the first optical path. When these series of preparatory work before starting processing are completed, the measurement control section 9 causes the laser oscillator 1 to oscillate and irradiates the laser beam 3. While the groove is being formed to obtain a desired resistance value, the measurement control section 9 checks the positioning of the resistor 62 on the second optical path and the focusing and scanning of the scan optical section 52. Trimming is performed while the resistance value of the resistor 61 is successively measured by the measurement control section 9. Immediately after one process is completed, the measurement control unit 9 controls the deflector 10 to deflect the laser beam 3 to the second optical path. Then, laser trimming of the resistor 62 is performed in the same manner. During this time, the measurement control unit 9 again selects the resistor 61 on the first optical path.
Performs positioning for the next process, etc. These tasks are
This process is repeated until all of the resistors 61 and 62 printed on the substrates 71 and 72 have been processed.
Note that the above-described series of preparatory operations before starting machining do not necessarily have to be performed in a fixed order, and can be changed depending on the content of trimming.

FIG. 4 is a timing chart showing the processing state of the laser trimming apparatus according to the present invention. Note that, similarly to FIG. 3, the horizontal axis represents the passage of time, and the vertical axis represents the amount of laser light irradiation. Further, ST1 indicates the processing state when the laser beam is deflected to the first optical path, and ST2 indicates the processing state when the laser beam is deflected to the second optical path. As is clear from this, the loss time during which the laser beam is not irradiated during the entire working time is small, and laser oscillation can be performed efficiently. If the time it takes for the circuit characteristics to stabilize when the circuit on the board 71 or the board 72 is operated, the time to measure the circuit characteristics, or the time to focus and scan the laser beam at a predetermined position, etc. The time during which laser oscillation is stopped can be reduced to zero by increasing the number of optical path deflections of the laser beam and increasing the scan optical section and station section accordingly. The deflector 10 may be a galvanometer-type optical scanner or one that mechanically rotates a mirror to deflect the deflector, but when dealing with an ultra-high-speed single pulse, an electro-optical switch having the Pockels effect may be used. It is preferable to adopt

〔Effect of the invention〕

According to the present invention, the laser beam oscillated from one laser oscillator can be laser trimmed at multiple locations via multiple scan optical sections using an arbitrary time division control method, thereby maximizing the laser oscillation time. It is possible to set the limit. Therefore, it is possible to dramatically improve laser oscillation efficiency. Furthermore, since the laser trimming device according to the present invention can perform processing at multiple locations, the processing capacity is dramatically increased compared to conventional laser trimming devices, and the investment efficiency for expensive equipment is extremely excellent. It can be done.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic structure of a conventional laser trimming device, FIG. 2 is a block diagram showing the basic structure of a laser trimming device according to an embodiment of the present invention, and FIG. 3 is a block diagram showing the basic structure of a conventional laser trimming device. FIG. 4 is a timing chart showing the processing state of a laser trimming apparatus according to an embodiment of the present invention. 1... Laser oscillator, 2... Q switch, 3...
...laser light, 4,41,42,43...reflector,
5, 51, 52...Scan optical section, 6, 61,
62...Workpiece, 7...Station part, 9...
...Measurement control section.

Claims (1)

[Claims] 1. A laser oscillator, a deflector that deflects the laser beam oscillated from the laser oscillator into two or more optical paths, and a laser beam deflected by the deflector that corresponds to each optical path and is focused on the workpiece and scanned. a station section on which a workpiece is placed, and a measurement control section that controls oscillation and stopping of the laser oscillator and scan control of the scan optical section according to the resistance value of the workpiece, etc. While trimming a certain workpiece, the measurement control unit positions the workpiece and controls the positioning of the workpiece in preparation for trimming another workpiece. A laser trimming device characterized in that the laser trimming device checks condensing and scanning of a scan optical section that condenses and scans the laser beam.