Underwater laser cutting device for single crystal gallium oxide

Abstract

The utility model discloses an underwater laser cutting device for single crystal gallium oxide. The underwater laser cutting device comprises a control unit, a laser processing unit, a liquid processing unit and a sample fixing device, the laser processing unit is used for performing laser cutting on the gallium oxide wafer; the sample fixing device is positioned in the liquid treatment unit; the liquid treatment unit is used for carrying out water flow scouring on the gallium oxide wafer in the laser processing process; the laser processing unit and the liquid processing unit are connected with the control unit, and the control unit is used for setting parameters of the laser processing unit and controlling the flow speed of the liquid processing unit. On the basis of a conventional underwater laser processing means, the laser underwater cutting device for gallium oxide is developed, and more excellent processing quality is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of gallium oxide processing, in particular to an underwater laser cutting device for single crystal gallium oxide. Background Art

[0002] Gallium oxide (β-Ga 2 O 3 ) As a new generation of semiconductor materials, it has the advantages of ultra-wide bandgap, high breakdown electric field strength, high ultraviolet transmittance, stable physical and chemical properties, etc. It can be widely used in microelectronics, optoelectronics, power devices and other fields. In the field of microelectronics, gallium oxide is used in the manufacture of devices such as high-frequency field effect transistors, surface acoustic wave filters and microwave switches because it can quickly respond to high-frequency electric fields. In the field of optoelectronics, its band gap matches visible light and is suitable for devices such as LED lights, thin-film solar panels and new photoelectric sensors. In the field of power devices, gallium oxide has a wide bandgap characteristic (~4.8eV) and can operate at higher voltages and power densities, and has higher performance potential than silicon carbide. Due to the characteristics of easy cleavage and high brittleness of gallium oxide, traditional mechanical processing methods are very likely to produce obvious cracks. By adopting laser processing, a non-contact processing method, material cracks can be reduced. However, during the laser processing process, there is often a large area of ​​heat-affected zone, and β-Ga 2 O 3 The thermal conductivity is low, and it is easy to crack due to uneven stress. In addition, if the molten material produced by laser processing is not removed in time, it will re-solidify and form a recast layer that is difficult to remove. Utility Model Content

[0003] The purpose of the utility model is to provide a laser underwater cutting device and method for single crystal gallium oxide, so as to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0004] The utility model adopts the following technical solutions to achieve the above utility model objectives:

[0005] The utility model provides an underwater laser cutting device for single crystal gallium oxide, comprising a control unit, a laser processing unit, a liquid processing unit and a sample fixing device;

[0006] The laser processing unit is used to perform laser cutting on the gallium oxide wafer;

[0007] The sample fixing device is located in the liquid handling unit;

[0008] The liquid processing unit is used to flush the gallium oxide wafer with water during the laser processing;

[0009] The laser processing unit and the liquid processing unit are respectively connected to the control unit. The control unit is used to set the parameters of the laser processing unit and also to control the flow rate of the liquid processing unit.

[0010] Furthermore, the liquid processing unit comprises two liquid storage tanks, a pump, a light-transmitting liquid tank and a filtering device which are sequentially connected through pipelines;

[0011] The sample fixing device is located in the light-transmitting liquid box;

[0012] The pump, the light-transmitting liquid tank and the filtering device are located between the two liquid storage tanks;

[0013] The filtering device is used to filter out solid suspended matter;

[0014] The two liquid storage tanks are communicated with each other through a pipeline.

[0015] Furthermore, the liquid used in the liquid processing unit is pure water or a weakly acidic aqueous solution.

[0016] Furthermore, the pH value of the weakly acidic aqueous solution ranges from 3 to 5.

[0017] Furthermore, the light-transmitting liquid box is made of light-transmitting glass.

[0018] Furthermore, the filtering device is equipped with a reverse osmosis membrane for filtering out solid suspended matter.

[0019] Further, the laser processing unit includes a laser, an optical scanning element and a focusing optical element arranged in sequence along the laser light path;

[0020] The laser is used to output a laser beam, which propagates in the form of rays and forms a laser light path;

[0021] The optical scanning element is used to control the spatial scanning position and trajectory of the light beam so that the laser spot moves along the cutting trajectory;

[0022] The focusing optical element is used to focus the light beam to form a laser spot.

[0023] Furthermore, the wavelength of the laser beam output by the laser is 310nm-380nm, the pulse width is less than 50ps, the peak power of the pulse is greater than 200kW, and the repetition frequency is greater than 100kHz.

[0024] The beneficial effects of the utility model are as follows:

[0025] The utility model develops a laser underwater cutting device for gallium oxide on the basis of conventional underwater laser processing means, thereby achieving more excellent processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of a laser underwater cutting device for single crystal gallium oxide provided according to an embodiment of the utility model;

[0027] Figure 2 The present invention is a flowchart of a processing method of a single crystal gallium oxide underwater laser cutting device provided according to an embodiment of the present invention.

[0028] In the figure:

[0029] 1. Control unit;

[0030] 2. Laser processing unit; 21. Laser; 22. Optical scanning element; 23. Focusing optical element;

[0031] 3. Liquid processing unit; 31. Liquid storage tank; 32. Pump; 33. Liquid pipe; 34. Translucent liquid tank; 35. Filtering device;

[0032] 4. Sample fixing device. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0034] Figure 1 Schematic diagram of the structure of the gallium oxide underwater laser cutting device constructed according to the preferred embodiment of the utility model. Figure 1 As shown, an underwater laser cutting device for single crystal gallium oxide includes a workbench and a control unit 1 arranged on the workbench, a laser processing unit 2 for cutting gallium oxide wafers, a liquid treatment unit 3 and a sample fixing device 4. The control unit 1 sets the scanning program and processing parameters of the laser processing unit 2 according to the three-dimensional model of gallium oxide. The control unit 1 sets the flow rate of the liquid treatment unit 3. The control unit 1 controls the mobile carrier to make the gallium oxide wafer to be processed reach the processing position, and then controls the laser processing unit 2 and the liquid treatment unit 3 to start, and after the cutting is completed, the sample is switched to continue cutting. After a period of time, the waste liquid is recycled and processed. The device adopts a fully sealed design to avoid the influence of water on the equipment in conventional water composite laser devices.

[0035] On the basis of the above structure, the laser processing unit 2 includes a pulse beam splitter, including: a laser 21, an optical scanning element 22 and a focusing optical element 23. The wavelength of the laser beam output by the laser 21 is 355nm, the laser beam output by the laser 21 is a pulse output, the pulse width is 20ps, the peak power of the pulse is 500kW, and the repetition frequency is 500kHz. The light beam output by the laser 21 propagates in the form of rays and forms a laser light path. The optical scanning element 22 and the focusing optical element 23 are arranged in sequence along the direction of the laser light path. The optical scanning element 22 is used to control the spatial scanning position and trajectory of the light beam so that the laser spot moves along a preset trajectory. Among them, the optical scanning element 22 controls the laser spot to form a sharp separation line or surface on the cutting trajectory; the separation line or surface extends in the longitudinal direction; the preset trajectory is tangent to the longitudinal direction so that the separation line or surface forms a cutting surface on the gallium oxide material to be cut. The focusing optical element 23 is used to focus the light beam to form a laser spot. The focusing optical element 23 is a focusing lens.

[0036] On the basis of the above structure, the laser processing unit 2 also includes a driving device arranged on the workbench. The output end of the driving device is fixedly connected to the laser processing unit 2 and is used to drive the laser processing unit 2 to perform lifting movements. The driving device is connected to the control unit 1. Here, the driving device can be selected as a cylinder or a motor screw, which can be selected according to actual needs.

[0037] On the basis of the above structure, the liquid processing unit 3 includes two liquid storage tanks 31 connected by pipelines, a pump 32, a liquid pipe 33, a light-transmitting liquid tank 34 and a filtering device 35. Its switch and flow rate are controlled by the control unit 1. The utility model adopts a light-transmitting liquid tank 34 to block the liquid phase, and the pump 32 drives the liquid to flow rapidly. Compared with the conventional underwater laser technology, it can provide a high-speed flushing effect of the liquid; and compared with the conventional water jet method, the present invention realizes the sealing and fluidity of the liquid at the same time. When the sample is flushed by the liquid during laser processing, the thickness of the surface liquid layer remains unchanged. Changes in the thickness of the surface liquid layer will cause the light beam to refract to varying degrees, causing the laser beam to defocus, resulting in a decrease in processing efficiency. The laser beam quality of the present invention is high and has a more excellent processing quality. The housing of the filtering device 35 is built with a reverse osmosis membrane for filtering solid suspended matter such as gallium oxide, specifically a polymer membrane, such as cellulose acetate membrane, aromatic polyamide membrane, polyether sulfone membrane, polyamide membrane, etc. Specifically, the solution in the liquid storage tank 31 is a weak acid solution, and the weak acid aqueous solution is composed of HCl, H 3 PO 4 , H 2 SO 4 , HNO 3 and CH 3At least one of COOH is dissolved in water, and the pH value of the weakly acidic aqueous solution ranges from 3 to 5. The configuration process of the weakly acidic solution in the preferred embodiment is as follows: (a) H3PO4 is mixed with pure water in a certain proportion until the pH of the solution reaches 3.8; (b) the above slurry is placed in the liquid storage tank 31 in advance. Gallium oxide is an amphoteric oxide that can react with acid to form a soluble gallium salt. It has been verified that when laser cutting gallium oxide underwater, a certain recast layer still exists after the sample is washed with water. After the commonly used water is adjusted to a weakly acidic aqueous solution, the heated and molten gallium oxide can react quickly with the weak acid to form a soluble gallium salt that dissolves in water and is taken away, thereby further reducing the recast layer, so that a product with a highly smooth cutting surface can be obtained. In addition, the weakly acidic solution is not enough to corrode the rest of the sample and will not have an adverse effect on the sample.

[0038] Figure 2 It is a flowchart of a processing method based on a gallium oxide cutting device constructed according to a preferred embodiment of the utility model, such as Figure 2 As shown, the specific steps of the processing method include:

[0039] S1, according to the three-dimensional model of the gallium oxide wafer to be processed, the control unit 1 slices the three-dimensional model to obtain multiple slice layers, and for each slice layer, sets the corresponding scanning path and processing parameters of the laser processing unit 2.

[0040] S2 , the control unit 1 sets the flow rate for the liquid processing unit 3 .

[0041] S3, placing the sample in the sample fixing device in the light-transmitting liquid box 34.

[0042] S4, the control unit 1 controls the laser processing unit 2 to start processing, and the control unit 1 controls the pump 32 of the liquid processing unit 3 to start high-speed rotation, so that the liquid flows at a high speed to flush the product on the sample surface.

[0043] S5, the laser processing unit 2 performs laser cutting on gallium oxide according to a preset scanning path, thereby completing the cutting of a single slice layer.

[0044] S6, the laser processing unit 2 decreases the thickness of one slice layer, and repeats steps S3-S4 until all slice layers are processed.

[0045] S7, perform fluid changes regularly.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A laser underwater cutting device for single crystal gallium oxide, characterized in that: It includes a control unit, a laser processing unit, a liquid processing unit and a sample fixing device; The laser processing unit is used to perform laser cutting on the gallium oxide wafer; The sample fixing device is located in the liquid handling unit; The liquid processing unit is used to flush the gallium oxide wafer with water during the laser processing; The laser processing unit and the liquid processing unit are respectively connected to the control unit, and the control unit is used to set the parameters of the laser processing unit and also to control the flow rate of the liquid processing unit; The liquid processing unit comprises two liquid storage tanks, a pump, a light-transmitting liquid tank and a filtering device connected in sequence through pipelines; The sample fixing device is located in the light-transmitting liquid box; The pump, the light-transmitting liquid tank and the filtering device are located between the two liquid storage tanks; The filtering device is used to filter out solid suspended matter; The two liquid storage tanks are communicated with each other through a pipeline.

2. The underwater laser cutting device for single crystal gallium oxide according to claim 1, characterized in that: The liquid used in the liquid treatment unit is pure water or a weakly acidic aqueous solution.

3. The underwater laser cutting device for single crystal gallium oxide according to claim 2, characterized in that: The pH value of the weakly acidic aqueous solution ranges from 3 to 5.

4. The underwater laser cutting device for single crystal gallium oxide according to claim 3, characterized in that: The light-transmitting liquid box is made of light-transmitting glass.

5. The underwater laser cutting device for single crystal gallium oxide according to claim 1, characterized in that: The filtering device is equipped with a reverse osmosis membrane for filtering out solid suspended matter.

6. The underwater laser cutting device for single crystal gallium oxide according to claim 1, characterized in that: The laser processing unit includes a laser, an optical scanning element and a focusing optical element arranged in sequence along the laser light path; The laser is used to output a laser beam, which propagates in the form of rays and forms a laser light path; The optical scanning element is used to control the spatial scanning position and trajectory of the light beam so that the laser spot moves along the cutting trajectory; The focusing optical element is used to focus the light beam to form a laser spot.

7. The underwater laser cutting device for single crystal gallium oxide according to claim 6, characterized in that: The wavelength of the laser beam output by the laser is 310nm-380nm, the pulse width is less than 50ps, the peak power of the pulse is greater than 200kW, and the repetition frequency is greater than 100kHz.

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