WO2021073485A1

WO2021073485A1 - Laser processing method and laser processing device

Info

Publication number: WO2021073485A1
Application number: PCT/CN2020/120536
Authority: WO
Inventors: 游盛天
Original assignee: 颀中科技（苏州）有限公司
Priority date: 2019-10-14
Filing date: 2020-10-13
Publication date: 2021-04-22
Also published as: CN110539070A

Abstract

A laser processing method comprises: setting a processing path; controlling a light source (11) to emit an incident beam, and using a beam-splitting module (12) to split the incident beam into at least two laser beams; controlling the beam-splitting module to rotate, such that the at least two laser beams rotate about a given axis and together form a processing beam; and controlling the processing beam to move along the processing path to complete processing of a component to be processed. In the method, a beam-splitting module is used to split an incident beam into at least two laser beams, and then the beam-splitting module is caused to rotate, such that the at least two laser beams rotate and together form a processing beam that can be uniformly distributed spatially, thereby improving the quality of laser grooving, etching, cutting, and the like. Also disclosed is a laser processing apparatus.

Description

Laser processing method and laser processing device

Technical field

The invention relates to the technical field of semiconductor production and equipment, in particular to a laser processing method and a laser processing device.

Background technique

As the semiconductor industry continues to develop in the direction of multi-function, precision, and integration, traditional mechanical slotting and cutting methods are gradually eliminated by the market. Compared with traditional mechanical processing technology, laser processing method has faster processing speed and higher processing accuracy, and can effectively solve the problems of chipping and cracking of semiconductor substrates.

In practical applications, due to the concentrated energy of a single laser beam and a large thermal damage area, it is easy to cause chip performance failure. Therefore, in the actual semiconductor processing process, a single laser beam is often divided into two or more sub-beams 101 by a beam splitting component. The predetermined substrate 201 is processed (as shown in FIGS. 1 and 2). The arrangement of the sub-beams is preset and remains fixed during the subsequent processing. However, due to the inconsistency of the light intensity in different regions of the sub-beams, the adjacent sub-beams often have a certain distance, resulting in the overall energy distribution of the processing beam The unevenness makes the etched groove body 202 inevitably have a height difference, and the flatness is poor.

In view of this, it is necessary to provide a new laser processing method and laser processing device.

Summary of the invention

The purpose of the present invention is to provide a laser processing method and a laser processing device, which can improve product processing quality and increase uniformity.

To achieve the above objective, the present invention provides a laser processing method, which mainly includes:

Set the processing path;

Control the light source to emit an incident light beam, and divide the incident light beam into at least two laser beams through the beam splitting module;

Control the driving module to drive the beam splitter module to rotate, so that at least two laser beams rotate along a predetermined axis and jointly form a processing beam;

The processing beam is controlled to move along the processing path to complete the processing of the component to be processed.

As a further improvement of the present invention, the laser processing method further includes arranging a masking plate on the surface of the component to be processed, the masking plate is provided with an opening that penetrates up and down and corresponds to the processing path, and the diameter of the processing beam is larger than The width of the opening.

As a further improvement of the present invention, in the process of "controlling the movement of the processing beam along the processing path", the center of the processing beam moves along the center line of the opening.

As a further improvement of the present invention, at least two laser beams are linearly arranged and arranged in two groups symmetrical to each other.

As a further improvement of the present invention, at least two laser beams are parallel to each other and have the same intensity.

As a further improvement of the present invention, at least two laser beams are arranged symmetrically with respect to the axis.

As a further improvement of the present invention, the processing beam is controlled to repeatedly move two or more times along the processing path.

As a further improvement of the present invention, the exit direction of the processing beam is adjusted to be perpendicular to the surface of the component to be processed.

As a further improvement of the present invention, the laser processing method further includes setting the intensity of the incident beam, the rotation speed of the beam splitter, and the moving speed of the processing beam.

The present invention also provides a laser processing device, including a light source, a beam splitting module, and a driving module. The beam splitting module is used to divide the initial laser light emitted by the light source into at least two laser beams. The driving module is used to drive the beam splitting module. When rotating, at least two laser beams form a processing beam together with the rotation of the beam splitting module.

The beneficial effect of the present invention is: using the laser processing method and the laser processing device of the present invention, the incident light beam emitted by the light source is divided into at least two laser beams by the beam splitting module, and the rotation of the beam splitting module causes the at least two laser beams to rotate together The processing beam with more uniform spatial distribution is formed, so that the wall surface after laser etching is smoother and the processing quality is improved.

Description of the drawings

Figure 1 is a schematic diagram of an existing laser processing process;

FIG. 2 is a schematic cross-sectional view of the substrate in FIG. 1 after processing is completed;

Figure 3 is a schematic diagram of the main flow of the laser processing method of the present invention;

4 is a schematic diagram of the processing process of a preferred embodiment of the laser processing method of the present invention;

5 is a schematic diagram of the module structure of the laser processing device of the present invention;

Fig. 6 is a schematic diagram of the processing process of another preferred embodiment of the laser processing method of the present invention.

Detailed ways

The present invention will be described in detail below in conjunction with the embodiments shown in the drawings. However, this embodiment does not limit the present invention, and the structural, method, or functional changes made by those skilled in the art according to this embodiment are all included in the protection scope of the present invention.

As shown in FIGS. 3 to 5, the laser processing device 100 provided by the present invention includes a light source 11, a beam splitting module 12, a driving module 13 and a control module 14. The light source 11 is used to emit an incident beam of a predetermined power and size; the beam splitting module 12 is used to split the incident beam emitted by the light source into at least two laser beams; the driving module 13 is used to drive the beam splitting module 12 is rotated so that at least two laser beams together form a processing beam S. Obviously, the light spot formed by the processing beam S on a plane perpendicular thereto is circular.

The light source 11 can be selected and determined according to the actual processing requirements of the component to be processed. The component to be processed can be a semiconductor substrate 200 which is a crystalline silicon wafer or is made of III-V semiconductor materials. The beam splitting module 12 is integrated in the corresponding laser head, which includes but is not limited to optical devices such as prisms, gratings, lenses, etc. The beam splitting module 12 can divide the incident beam into a plurality of laser beams arranged linearly or rectangularly. The driving module 13 can drive the spectroscopic module 12 to rotate along a predetermined axis according to an instruction issued by the control module 14. Of course, the rotation speed of the spectroscopic module 12 can be set and adjusted by the control module 14.

The emission directions of at least two laser beams are the same, and the at least two laser beams are arranged symmetrically with respect to the axis. Preferably, the intensity of at least two laser beams emitted from the beam splitting module 12 is the same, so that the intensity of the processing beam S is more uniform. Here, at least two laser beams are linearly arranged and arranged in two groups symmetrical to each other with respect to the axis. The processing beam S shown in FIG. 4 is composed of two laser beams that are spaced apart and emitted in parallel and rotate along the same axis, wherein the two laser beams are arranged symmetrically with respect to the axis.

The laser processing method provided by the present invention includes:

Set the processing path and processing parameters;

Controlling the light source 11 to emit a predetermined incident light beam toward the light splitting module 12, and the light splitting module 12 divides the incident light beam into at least two laser beams and emits them outward;

Control the driving module 13 to drive the beam splitting module 12 to rotate, so that at least two lasers rotate along a predetermined axis and jointly form a processing beam S;

The processing beam S is controlled to move along the processing path to complete the processing of the component to be processed.

The processing parameters include the intensity of the incident light beam emitted by the light source 11, the rotation speed of the beam splitting module 12, the moving speed of the processing light beam S, and the like. The control module 14 can also be used to store the above-mentioned processing parameters, so as to facilitate repeated processing of batches of components to be processed. Of course, according to the processing requirements of the component 200 to be processed, the control module 14 may also control the processing beam S to repeatedly move along the processing path two or more times.

The laser processing method further includes adjusting the exit direction of the processing beam S to be perpendicular to the surface of the component to be processed. Here, the semiconductor substrate 200 can be fixed along the exit direction perpendicular to the processing beam S, and then the semiconductor substrate 200 can be processed by the processing beam S, and the groove 21 obtained by the processing beam S can be etched. The chip units 22 on the semiconductor substrate 200 are separated from each other.

As shown in FIG. 6, in another embodiment of the present invention, when the width of the slot 21 is required to be smaller than the diameter of the processing beam S, the laser processing method further includes providing a method for laying on the semiconductor substrate 200 The masking plate 300 on the surface of the masking plate 300 is provided with an opening 301 that penetrates up and down and corresponds to the processing path, and the diameter of the processing beam S is greater than the width of the opening 301;

The processing beam S is controlled to move along the center line of the opening 301 to complete processing.

The masking plate 300 can meet the processing requirements of slots 21 of different widths; and, when the processing beam S moves along the center line of the opening 301, the edge portions S1 on both sides of the processing beam S When irradiated on the masking plate 300, the edge part S1 has a lower energy density and does not participate in the processing of the corresponding semiconductor substrate 200; relatively, the middle part S2 of the processing beam S used for the processing of the semiconductor substrate 200 has a more uniform intensity Therefore, the inner wall of the slot 21 after the etching is smoother, and the processing quality is improved.

In summary, the laser processing method and laser processing device 100 of the present invention divide the incident light beam emitted by the light source 11 into at least two laser beams by the beam splitting module 12, and then drive the rotation of the beam splitting module 12 to make the at least two laser beams The laser is rotated together to form a processing beam S with a more uniform spatial distribution, which improves the quality of laser processing.

It should be understood that although this specification is described in accordance with the implementation manners, not each implementation manner only includes an independent technical solution. This narration in the specification is only for the sake of clarity, and those skilled in the art should regard the specification as a whole. The technical solutions in the embodiments can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

The series of detailed descriptions listed above are only specific descriptions of feasible implementations of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementations or implementations made without departing from the technical spirit of the present invention All changes shall be included in the protection scope of the present invention.

Claims

A laser processing method, characterized in that:

Set the processing path;

Control the light source to emit an incident light beam, and divide the incident light beam into at least two laser beams through the beam splitting module;

Control the driving module to drive the beam splitter module to rotate, so that at least two laser beams rotate along a predetermined axis and jointly form a processing beam;

The processing beam is controlled to move along the processing path to complete the processing of the component to be processed.
The laser processing method according to claim 1, characterized in that: the laser processing method further comprises arranging a masking plate on the surface of the component to be processed, the masking plate is provided with openings that penetrate up and down and correspond to the processing path , The diameter of the processing beam is greater than the width of the opening.
The laser processing method according to claim 2, wherein in the process of "controlling the movement of the processing beam along the processing path", the center of the processing beam moves along the center line of the opening.
The laser processing method according to claim 1, wherein at least two laser beams are linearly arranged and arranged in two groups symmetrical to each other.
The laser processing method according to claim 1, wherein at least two laser beams are parallel to each other and have the same intensity.
The laser processing method according to claim 1, wherein at least two laser beams are arranged symmetrically with respect to the axis.
The laser processing method according to claim 1, wherein the processing beam is controlled to move repeatedly along the processing path two or more times.
The laser processing method according to claim 1, wherein the exit direction of the processing beam is adjusted to be perpendicular to the surface of the component to be processed.
The laser processing method according to claim 1, wherein the laser processing method further comprises setting the intensity of the incident beam, the rotation speed of the beam splitter, and the moving speed of the processing beam.
A laser processing device, characterized in that: the laser processing device comprises a light source, a beam splitting module and a driving module, the beam splitting module is used to divide the initial laser light emitted by the light source into at least two laser beams, and the driving module is used for The light splitting module is driven to rotate along a predetermined axis, and at least two laser beams form a processing beam together with the rotation of the light splitting module.
10. The laser processing device according to claim 10, wherein at least two laser beams are linearly arranged and arranged in two groups symmetrical to each other.
10. The laser processing apparatus according to claim 10, wherein at least two laser beams are parallel to each other and have the same intensity.
10. The laser processing apparatus according to claim 10, wherein at least two laser beams are arranged symmetrically with respect to the axis.