KR20140035015A

KR20140035015A - Laser processing apparatus

Info

Publication number: KR20140035015A
Application number: KR1020120101084A
Authority: KR
Inventors: 이근유; 천세경; 윤영수
Original assignee: 삼성전기주식회사
Priority date: 2012-09-12
Filing date: 2012-09-12
Publication date: 2014-03-21

Abstract

Laser processing apparatus according to an embodiment of the present invention comprises a laser oscillator for oscillating a laser beam to process a hole in the substrate; At least one mirror reflecting the laser beam to irradiate the laser beam to a predetermined machining position on the substrate; An optical system for condensing the laser beam; A laser scanner for advancing the laser beam to irradiate the laser beam to a position where holes are to be processed in the substrate; A beam splitter disposed between the laser scanner and the optical system, the beam splitter reflecting a part of the laser beam and transmitting a remainder; A sensor for detecting positional information of the laser beam from the laser beam reflected by the beam splitter; And a motor that changes the position of the mirror based on the position information detected by the sensor.

Description

Laser processing apparatus

The present invention relates to a laser processing apparatus, and more particularly, to a laser processing apparatus capable of processing a hole at a precise position of a substrate.

In general, a number of holes are formed on the substrate such as via holes electrically connecting the substrates.

In this case, thousands to hundreds of thousands of holes are formed in the substrate. A laser processing apparatus using a laser beam is most commonly used to process so many holes in a substrate.

The laser processing apparatus uses a method of positioning a substrate on a stage, adjusting an angle so that a laser is emitted onto the substrate using a scanner device, and processing a hole at a desired position according to a command of pre-designed processing position data. It has the advantage of making holes on the substrate faster and more accurately than other methods.

However, the use of the laser processing method does not provide a satisfactory accuracy of the hole position, and errors in the position where the hole is processed often occur due to various factors.

That is, the position and direction in which the laser beam is output may change according to the internal temperature of the laser oscillator where the laser is emitted. The higher the output of the laser beam, the greater the amount of heat absorbed by the optical system. The position of the laser beam may change.

In addition, a change may occur in the final output position of the laser beam due to a change in reflection or refractive index by an optical component located on the optical path of the laser beam.

As a result, when the position of the laser beam is changed, an error occurs with respect to the position of the hole to be processed on the substrate. As such a machining error occurs, the reliability of the product decreases, and in severe cases, the hole is processed at a completely different position. There is a defect that cannot use the product itself.

Therefore, there is a need for techniques for processing holes in the correct position of the substrate by correcting the error for the above factors.

An object according to an embodiment of the present invention is to provide a laser processing apparatus capable of processing a hole at a precise position of a substrate by adjusting a position of a mirror to correct a position of a laser beam reflected by the mirror.

Laser processing apparatus according to an embodiment of the present invention comprises a laser oscillator for oscillating a laser beam to process a hole in the substrate; At least one mirror reflecting the laser beam to irradiate the laser beam to a predetermined machining position on the substrate; An optical system for condensing the laser beam; A laser scanner for advancing the laser beam such that the laser beam is irradiated to a position where a hole is to be processed in the substrate; A beam splitter disposed between the laser scanner and the optical system, the beam splitter reflecting a part of the laser beam and transmitting a remainder; A sensor for detecting positional information of the laser beam from the laser beam reflected by the beam splitter; And a motor that changes the position of the mirror based on the position information detected by the sensor.

The laser scanner of the laser processing apparatus according to an embodiment of the present invention may include any one of a galvano mirror, a polygon mirror, and a digital mirror.

Laser processing apparatus according to an embodiment of the present invention may further include a control unit for providing a drive signal to the motor.

The optical system of the laser processing apparatus according to an embodiment of the present invention may include a beam shaper for making the energy density of the laser beam uniform.

The optical system of the laser processing apparatus according to an embodiment of the present invention may further include a light collecting unit for condensing the laser beam.

The motor of the laser processing apparatus according to an embodiment of the present invention may be mounted on a mirror located closest to the laser scanner.

According to the laser processing apparatus according to the present invention, the hole can be processed at the correct position of the substrate by adjusting the position of the mirror to correct the position of the laser beam reflected by the mirror.

1 is a schematic configuration diagram of a laser processing apparatus according to an embodiment of the present invention.
Figure 2 is a block diagram showing a state of correcting the position of the mirror of the laser processing apparatus according to an embodiment of the present invention.

Hereinafter, with reference to the drawings will be described in detail a specific embodiment of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept. Other embodiments falling within the scope of the inventive concept may readily be suggested, but are also considered to be within the scope of the present invention.

In addition, the components with the same functions within the scope of the same idea shown in the drawings of the embodiments will be described using the same reference numerals.

1 is a schematic configuration diagram of a laser processing apparatus according to an embodiment of the present invention, Figure 2 is a configuration diagram showing a state of correcting the position of the mirror of the laser processing apparatus according to an embodiment of the present invention.

1 and 2, a laser processing apparatus according to an exemplary embodiment of the present invention may include a laser oscillation apparatus 110, a mirror unit 120, an optical system 130, a beam splitter 210, and a laser scanner 140. , A sensor 220, a controller 230, and a motor 240 may be included.

The laser oscillation apparatus 110 may generate a laser beam L therein, and may oscillate the laser beam L in one direction.

The laser beam L oscillated in one direction becomes a laser beam L of a suitable shape for processing holes on the substrate 100 through the optical system 130.

Accordingly, the laser beam L emitted from the laser oscillator 110 may serve to form a hole in the substrate 100 by traveling on the substrate 100.

The mirror unit 120 is positioned on the optical path of the laser beam L emitted from the laser oscillator 110, and the laser beam L is irradiated to a machining position preset on the substrate 100. The laser beam L may be reflected.

1 illustrates a case in which three mirrors 121, 123, and 125 are used in a laser processing apparatus according to an embodiment of the present invention, but the spirit of the present invention is not limited to the number of the mirrors, and the working environment. In some cases, one mirror may be used, and a plurality of mirrors may be used.

The optical system 130 processes the laser beam L emitted from the laser oscillator 110 and irradiates the laser beam L to a predetermined position on the substrate 100.

Therefore, the laser beam L reflected by the mirror unit 120 becomes a laser beam L of a suitable type for processing holes on the substrate 100 while passing through the optical system 130.

The optical system 130 may include a beam shaper 131 for uniforming the energy density of the laser beam L, and a light condenser 133 for condensing the laser beam L. FIG.

The beam splitter 210 may refer to a reflector or other optical device that reflects a part of the laser beam L and transmits the other part.

That is, the beam splitter 210 may reflect a portion of the laser beam L transmitted from the optical system 130, and transmit the rest of the beam splitter 210.

The laser beam L reflected by the beam splitter 210 may be transmitted to the sensor 220, and the sensor 220 may detect position information of the laser beam L.

The controller 230 may calculate an error by comparing the position information of the laser beam L detected by the sensor 220 with an initial position, and transmit a motor driving signal according to the error to the motor 240. have.

The motor 240 may be mounted on the mirror 120 to drive the mirror 120, and receive a driving signal from the controller 230 to correct the position of the mirror 120. Can be.

Here, when the plurality of mirrors 121, 123, 125 are used in the laser driving device, the motor 240 may be mounted on the mirror 125 positioned closest to the laser scanner 140 described later.

Errors may accumulate as a plurality of mirrors 121, 123, and 125 are used, thereby minimizing hole machining errors by mounting the motor 240 to the mirror 125 that is closest to the laser scanner 140. Can be.

The motor 240 may be mounted on the mirror 125 positioned closest to the laser scanner 140 to move the mirror 125 in the X-axis direction and the Y-axis direction.

The laser scanner 140 may function to advance the laser beam L passing through the beam splitter 210 toward the substrate 100.

The laser scanner 140 uses a galvano mirror to change the direction of the beam. The laser scanner 140 may arbitrarily change the direction of the beam by adjusting the angle of the galvano mirror according to a designer's intention.

In this embodiment, the beam is changed using a galvano mirror, but it is also possible to use one of a polygon mirror and a digital mirror.

The laser scanner 140 is electrically connected to a scanner controller (not shown) that controls a value for changing the angle of the galvano mirror.

2, L1 means a laser beam before the position is corrected, L2 means a laser beam after the position is corrected.

The laser beam reflected by the mirror unit 120 may be changed in position due to various factors, and the hole may not be accurately processed at a predetermined position in the substrate 100 due to the position error.

However, by moving the mirror 125 located closest to the laser scanner 140 through the motor 240, the laser beam can be irradiated to a desired position.

That is, the laser beam L1 before the position is corrected is reflected by the beam splitter 210, and the sensor 220 detects the position information from the reflected laser beam L1.

In addition, the controller 230 calculates an error by comparing the position information with the initial position information, and provides a motor driving signal according to the error to the motor 240 so that the motor 240 moves the mirror 125. By doing so, holes may be processed at the correct position of the substrate 100.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be apparent to those skilled in the art that such modifications or variations are within the scope of the appended claims.

100: substrate 110: laser oscillation device
120: mirror 130: optical system
140: laser scanner 210: beam splitter
220: sensor 230: control unit
240: motor

Claims

A laser oscillator for oscillating a laser beam to process holes in the substrate;
At least one mirror reflecting the laser beam to irradiate the laser beam to a predetermined machining position on the substrate;
An optical system for condensing the laser beam;
A laser scanner for advancing the laser beam such that the laser beam is irradiated to a position where a hole is to be processed in the substrate;
A beam splitter disposed between the laser scanner and the optical system, the beam splitter reflecting a part of the laser beam and transmitting a remainder;
A sensor for detecting positional information of the laser beam from the laser beam reflected by the beam splitter; And
And a motor for changing the position of the mirror based on the positional information detected by the sensor.

The method of claim 1,
The laser scanner includes any one of a galvano mirror, a polygon mirror and a digital mirror.

The method of claim 1,
And a control unit for providing a driving signal to the motor.

The method of claim 1,
The optical system comprises a beam shaper for uniforming the energy density of the laser beam.

5. The method of claim 4,
The optical system further comprises a light collecting part for condensing the laser beam.

The method of claim 1,
The motor is a laser processing apparatus mounted to the mirror that is located nearest to the laser scanner.