CN109483067B - A computer-controlled laser processing device and its processing method - Google Patents

Abstract

The invention provides a computer-controlled laser processing device and a processing method thereof, which can realize simultaneous cutting of multiple cutting lanes, at the same time ensure the verticality of the cutting lanes, and can flexibly control the spacing between the cutting lanes; this kind of cutting, It can reduce cracks and chips to the greatest extent, and control the energy of the first laser to control the cutting speed; using all computer controls to achieve precise control and prevent improper cutting operations.

Description

A computer-controlled laser processing device and its processing method

technical field

The invention relates to the field of semiconductor wafer cutting, in particular to a computer-controlled laser processing device and a processing method thereof.

Background technique

The cutting of silicon wafers or other semiconductor wafers is often performed by mechanical cutting or laser cutting, in which laser cutting has the beneficial effect of preventing the risk of chips and cracks; however, existing laser cutting devices often only cut one dividing line at a time, or cut The spacing of multiple cutting lines is fixed, which is not conducive to the speed and flexibility of cutting; in addition, if the laser head or laser system is inclined in the vertical direction, that is, not perpendicular to the silicon wafer, the cutting line will be cut. Tilting can also occur, and this cut can lead to failure of the cut single piece.

SUMMARY OF THE INVENTION

Based on solving the above problems, the present invention provides a computer-controlled laser processing device, including:

a first laser that emits a first laser beam along a first optical axis;

a second laser, the second laser emits a second laser beam along a second optical axis, and the first optical axis and the second optical axis are perpendicular to each other;

an optical system, the optical system includes a first condenser lens, an optical fiber branch assembly and a second condenser lens arranged in sequence along the first optical axis; the optical fiber branch assembly includes a beam splitter and an optical fiber bundle assembly, the optical fiber bundle assembly is arranged in the extending direction of the first optical axis of the beam splitter; the optical fiber bundle assembly includes a plurality of optical fiber bundles and a hexahedral reflection cover, the optical fiber bundles are evenly distributed in the reflection cover, and the reflection cover is used for reflecting the second laser beam;

a half-mirror, the half-mirror is arranged on the second optical axis path, an alignment mark is arranged on the reflection surface of the half-mirror, and can reflect the second laser beam reflected by the reflection cover, The reflected second beam is defined as a reflected beam;

an optical receiver that receives the reflected light beam;

A computer control system, the computer control system includes an image acquisition unit, a vertical controller and a horizontal controller, the image acquisition unit collects the reflected light beam received by the light receiver, and the vertical controller is used for according to the image acquisition unit. The collected reflected light beam adjusts the optical fiber branch assembly to be parallel to the first optical axis, and the level controller is configured to adjust the relative position of the optical fiber branch assembly relative to the optical fiber branch assembly according to the reflected light beam collected by the image acquisition unit. the rotation angle of the second optical axis.

According to an embodiment of the present invention, it further includes a longitudinal stepping motor for adjusting the optical fiber splitting assembly to be parallel to the first optical axis, and the vertical controller controls the longitudinal stepping motor to realize the optical fiber splitting. The longitudinal direction of the path assembly is parallel to the first optical axis.

According to an embodiment of the present invention, it further includes a lateral stepping motor for adjusting the angle between the optical fiber splitting assembly and the second optical axis, and the horizontal controller controls the lateral stepping motor to realize the optical fiber splitting Adjustment of the rotation angle between the assembly and the second optical axis.

According to an embodiment of the present invention, a movable stage is further included, and the stage is used for carrying the workpiece to be cut.

According to an embodiment of the present invention, the computer control system further includes a movement controller for controlling the directional movement of the stage.

According to an embodiment of the present invention, the computer control system further includes a first laser controller and a second laser controller, which are used to respectively control the working state and laser intensity of the first laser and the second laser.

According to an embodiment of the present invention, a scale is provided on the reflector, and the scale is an angle scale for measuring the rotation angle A of the optical fiber branching system relative to the second optical axis in the horizontal direction.

According to an embodiment of the present invention, the 0-degree position of the angle scale is the extended position of the arrangement of the plurality of optical fiber bundles.

The present invention also provides a computer-controlled laser processing method, which uses the above-mentioned computer-controlled laser processing device, and the method includes the following steps:

(1) providing a semiconductor wafer, and supporting the semiconductor wafer on the stage;

(2) Using the second laser controller to control the second laser to emit a second laser beam, the second laser beam passes through the half mirror and is reflected by the reflector, and the half mirror reflects and conducts to the light receiver , and the optical signal is captured by the image acquisition unit;

(3) the vertical controller is configured to adjust the optical fiber branch assembly to be parallel to the first optical axis according to the reflected light beam collected by the image acquisition unit;

(4) According to the required cutting spacing d2 of the semiconductor wafer, the horizontal controller adjusts the rotation angle A of the optical fiber branch assembly relative to the second optical axis according to the reflected light beam collected by the image acquisition unit;

(5) Fixing the fiber shunt assembly, using the first laser controller to control the first laser to emit a first laser beam onto the semiconductor wafer, and using the movement controller to control the horizontal movement of the stage to realize cutting.

According to an embodiment of the present invention, the plurality of optical fiber bundles are uniformly distributed in the lateral direction, and their spacing is d1, where d2=|d1 ×cosA|.

The advantages of the present invention are as follows:

(1) Multiple cutting lanes can be cut at the same time, while ensuring the verticality of the cutting lanes, and flexibly controlling the spacing between the cutting lanes;

(2) This kind of cutting can reduce cracks and debris to the greatest extent, and control the energy of the first laser and the cutting speed;

(3) Utilize all computer control to achieve precise control and prevent improper operation of cutting.

Description of drawings

1 is a schematic diagram of a computer-controlled laser processing device of the present invention;

Fig. 2 is the schematic diagram of the computer control system of the present invention;

3A and 3B are schematic diagrams of angular rotation of the optical fiber splitter assembly of the present invention;

4A and 4B are schematic views of the scale of the fiber optic splitter assembly of the present invention.

Detailed ways

1, the computer-controlled laser processing device of the present invention includes:

a first laser 1 that emits a first laser beam 2 along a first optical axis;

a second laser 12, the second laser 12 emits a second laser beam 13 along a second optical axis, and the first optical axis and the second optical axis are perpendicular to each other;

an optical system, the optical system includes a first condenser 3, an optical fiber branch assembly 4 and a second condenser 10 arranged in sequence along the first optical axis; the optical fiber branch assembly 4 includes a beam splitter 5 and an optical fiber bundle assembly, The optical fiber bundle assembly is arranged in the extending direction of the first optical axis of the beam splitter 5; the optical fiber bundle assembly 4 includes a plurality of optical fiber bundles 7 and a hexahedral reflector 6, and the optical fiber bundles 7 are evenly distributed in the Inside the reflector 6, the reflector 6 is used to reflect the second laser beam 13; wherein, the beam splitter 5 and the fiber bundle assembly are fixed to each other;

A half mirror 14, the half mirror 14 is arranged on the second optical axis path, an alignment mark (not shown) is arranged on the reflection surface of the half mirror 14, and can reflect the reflector 6 The reflected second laser beam 13, the reflected second beam is defined as a reflected beam;

an optical receiver 15, the optical receiver 15 receives the reflected light beam;

2, also includes a computer control system, the computer control system includes a central processing unit, a display, an image acquisition unit, a vertical controller and a horizontal controller, and the image acquisition unit collects the reflected light beam received by the light receiver 15, The vertical controller is used to adjust the optical fiber branch assembly 4 to be parallel to the first optical axis according to the reflected light beam collected by the image acquisition unit, and the horizontal controller is used to The reflected light beam adjusts the rotation angle A of the optical fiber splitting assembly 4 relative to the second optical axis.

Near the optical fiber splitting assembly 4, there is also a longitudinal stepping motor 8 for adjusting the optical fiber splitting assembly 4 to be parallel to the first optical axis, and the vertical controller controls the longitudinal stepping motor 8 In order to realize that the optical fiber branch assembly 4 is longitudinally parallel to the first optical axis; it also includes a lateral stepping motor 9 for adjusting the angle between the optical fiber branch assembly 4 and the second optical axis, and the horizontal controller controls the The lateral stepping motor 9 is used to adjust the rotation angle of the optical fiber branch assembly 4 relative to the second optical axis in the horizontal direction.

There is a movable stage 11 at the end position of the first optical axis, and the stage 11 is used for carrying the workpiece 100 to be cut; the computer control system further includes a movement controller for controlling the directional movement of the stage 11 .

According to an embodiment of the present invention, the computer control system further includes a first laser controller and a second laser controller, which are used to respectively control the working states and laser intensity of the first laser 1 and the second laser 12 .

3A-3B, the optical fiber splitter assembly 4 can be rotated along the central axis, and its rotation is realized by a lateral stepping motor, which has been described in the foregoing content and will not be repeated; its reference lines are multiple The straight line arranged by the fiber bundles 7, the spacing between the multiple fiber bundles is d1, and the rotation angle is A, then the spacing between the finally cut scribe lines is d2=|d1×cosA|.

4A-4B, a scale is provided on the reflector 6, and the scale is an angle scale for measuring the rotation angle A of the optical fiber branching system along the direction of the second optical axis. The display is adjusted to be vertical and the rotation angle A is adjusted by the relative position of the alignment mark and the scale.

Using the above computer-controlled laser processing device, the present invention also provides a computer-controlled laser processing method, which comprises the following steps:

(1) Provide a semiconductor wafer (workpiece 100 ), and support the semiconductor wafer on the stage 11 ;

(2) Using the second laser controller to control the second laser 12 to emit a second laser beam 13 , the second laser beam 13 passes through the half mirror 14 and is reflected by the reflector 6 and reflected by the half mirror 14 Conducted to the light receiver 15, and the light signal is captured by the image acquisition unit;

(3) The vertical controller is configured to adjust the optical fiber branch assembly 4 to be parallel to the first optical axis according to the reflected light beam collected by the image acquisition unit;

(4) According to the required cutting distance d2 of the semiconductor wafer, the horizontal controller adjusts the rotation angle A of the optical fiber branch assembly 4 relative to the second optical axis according to the reflected light beam collected by the image acquisition unit ;

(5) Fixing the optical fiber shunt assembly 4, using the first laser controller to control the first laser 1 to emit the first laser beam 2 onto the semiconductor wafer, and using the movement controller to control the horizontal movement of the stage 11, for cutting.

Wherein, the plurality of optical fiber bundles are uniformly distributed in the lateral direction, and their spacing is d1, where d2=|d1×cosA|.

Finally, it should be noted that: obviously, the above-mentioned embodiments are only examples for clearly illustrating the present invention, and are not intended to limit the implementation manner. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. However, the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (10)

1. A computer-controlled laser machining apparatus comprising:

a first laser emitting a first laser beam along a first optical axis;

a second laser emitting a second laser beam along a second optical axis, the first and second optical axes being perpendicular to each other; it is characterized by also comprising: the optical system comprises a first condenser, an optical fiber branching assembly and a second condenser which are sequentially arranged along the direction of a first optical axis; the optical fiber branching assembly comprises a spectroscope and an optical fiber bundle assembly, and the optical fiber bundle assembly is arranged in the extending direction of a first optical axis of the spectroscope; the optical fiber bundle assembly comprises a plurality of optical fiber bundles and a hexahedral reflecting cover, the optical fiber bundles are uniformly distributed in the reflecting cover, and the reflecting cover is used for reflecting the second laser beam;

the half mirror is arranged on the second optical axis path, an alignment mark is arranged on the reflecting surface of the half mirror, the half mirror can reflect the second laser beam reflected by the reflector, and the reflected second laser beam is defined as a reflected light beam;

a light receiver that receives the reflected light beam;

the computer control system comprises an image acquisition unit, a vertical controller and a horizontal controller, wherein the image acquisition unit acquires a reflected light beam received by the light receiver, the vertical controller is used for adjusting the optical fiber shunt assembly to be parallel to the first optical axis according to the reflected light beam acquired by the image acquisition unit, and the horizontal controller is used for adjusting the rotation angle of the optical fiber shunt assembly relative to the second optical axis according to the reflected light beam acquired by the image acquisition unit.

2. The computer-controlled laser machining apparatus of claim 1, further comprising a longitudinal stepper motor that aligns the fiber splitting assembly parallel to the first optical axis, the vertical controller controlling the longitudinal stepper motor to achieve the fiber splitting assembly longitudinally parallel to the first optical axis.

3. The computer-controlled laser processing apparatus according to claim 1, further comprising a lateral stepping motor that adjusts an angle of the optical fiber branching assembly with respect to the second optical axis, wherein the horizontal controller controls the lateral stepping motor to effect adjustment of a rotation angle of the optical fiber branching assembly with respect to the second optical axis.

4. The computer-controlled laser machining apparatus of claim 1, further comprising a movable stage for carrying a work piece to be cut.

5. The computer-controlled laser machining apparatus of claim 4, wherein the computer control system further comprises a movement controller for controlling directional movement of the stage.

6. The computer-controlled laser machining apparatus of claim 1, wherein the computer control system further comprises a first laser controller and a second laser controller for controlling the operating status and laser intensity of the first laser and the second laser, respectively.

7. The computer-controlled laser processing apparatus according to claim 1, wherein a scale is provided on the reflection housing, and the scale is an angle scale for measuring a rotation angle a of the optical fiber branching assembly in a horizontal direction with respect to the second optical axis.

8. The computer-controlled laser processing apparatus according to claim 7, wherein the 0-degree position of the angular scale is an extended position of the plurality of fiber bundle arrangements.

9. A computer-controlled laser machining method using the computer-controlled laser machining apparatus of claim 5, the method comprising the steps of:

(1) providing a semiconductor wafer, and clamping the semiconductor wafer on the carrying platform;

(2) a second laser controller is utilized to control a second laser to emit a second laser beam, the second laser beam penetrates through the half-reflecting mirror and is reflected by the reflecting cover, the half-reflecting mirror reflects and transmits the second laser beam to the light receiver, and an image acquisition unit captures an optical signal;

(3) the vertical controller is used for adjusting the optical fiber branching component to be parallel to the first optical axis according to the reflected light beam collected by the image collecting unit;

(4) according to the required cutting spacing d2 of the semiconductor wafer, the horizontal controller adjusts the rotation angle A of the optical fiber branching assembly relative to the second optical axis according to the reflected light beam collected by the image collecting unit;

(5) and fixing the optical fiber branching assembly, controlling a first laser to emit a first laser beam onto the semiconductor wafer by using a first laser controller, and controlling the horizontal movement of the carrying platform by using a movement controller so as to realize cutting.

10. The computer-controlled laser machining method of claim 9, wherein the plurality of fiber bundles are uniformly distributed in a lateral direction and spaced apart by a distance d1, wherein d2 ═ d1 × cosA |.

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