A method for laser separating a diamond single crystal

Abstract

The application relates to a method for separating a diamond single crystal by laser, and relates to the technical field of diamond cutting. A modified layer is formed on the single crystal diamond by a picosecond laser, and then the single crystal diamond is separated along the modified layer by a cleaving machine. The application has the advantages of high efficiency, high product breaking resistance, no taper on the broken surface, and no ablation marks on the upper and lower surfaces.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of diamond cutting, and particularly relates to a method for laser separating diamond single crystals. BACKGROUND

[0002] The principle of traditional laser cutting is that diamond material is instantaneously gasified under laser irradiation. Due to a series of advantages such as short laser action time, small light spot and narrow cutting seam, the traditional laser cutting is often applied to cutting of large-size single crystal diamond. However, the traditional laser cutting technology has problems such as easy breakage, low efficiency, taper of cutting section, and ablation marks on upper and lower surfaces after cutting. SUMMARY

[0003] In view of the problems in the prior art, one of the purposes of the present application is to provide a method for laser separating diamond single crystals, which has the advantages of high efficiency, non-breakable product, no taper of cutting section, and no ablation marks on upper and lower surfaces.

[0004] The above purpose of the present application is achieved by the following technical scheme:

[0005] The method for laser separating diamond single crystals forms a modified layer on the single crystal diamond by using a picosecond laser, and then separates the single crystal diamond along the modified layer by using a cleaving machine.

[0006] By adopting the above technical scheme, the modified layer is set, and then the single crystal diamond is separated along the modified layer by using the cleaving machine, so that the purposes of high efficiency, non-breakable product, no taper of cutting section, and no ablation marks on upper and lower surfaces are achieved.

[0007] In a preferred example, the present application can be further configured as: the modified layer is a plurality of layers.

[0008] By adopting the above technical scheme, the cleaving machine has better effect when cleaving.

[0009] In a preferred example, the present application can be further configured as: the picosecond laser is a 1064 laser source with a pulse width less than 15 picoseconds.

[0010] By adopting the above technical scheme, the effect of forming the modified layer is better.

[0011] In a preferred example, the present application can be further configured as: the laser frequency is 100 KHz, the laser energy is 1 W, and the processing speed is 200 mm / s.

[0012] By adopting the above technical scheme, the effect of forming the modified layer is better.

[0013] The application can be further configured in a preferred example that, when forming the modified layer, the laser forms the modified layer inside the single crystal diamond in a direction perpendicular to the surface of the single crystal diamond, the interlayer spacing of the modified layer is 50 um, the layer power attenuation of the laser is 3%, and the number of processed layers is 10 layers.

[0014] By adopting the technical scheme, the effect is better when the single crystal diamond is cracked.

[0015] The application can be further configured in a preferred example that the cracking machine comprises a bearing table, and the bearing table is provided with a negative pressure hole, and when the single crystal diamond is placed on the bearing table, the single crystal diamond covers the negative pressure hole.

[0016] By adopting the technical scheme, the existence of the negative pressure hole can position the single crystal diamond in use, thereby reducing the probability of displacement of the single crystal diamond in the cracking process.

[0017] The application can be further configured in a preferred example that the bearing table is further provided with a rubber layer for contacting the single crystal diamond, the negative pressure hole penetrates the rubber layer, the rubber layer is provided with a pattern, and the single crystal diamond does not completely cover the pattern.

[0018] By adopting the technical scheme, the existence of the pattern can reduce the contact area between the single crystal diamond and the rubber layer, thereby facilitating the taking of the single crystal diamond.

[0019] The application can be further configured in a preferred example that after the single crystal diamond is placed on the bearing table, suction is performed through the negative pressure hole, the single crystal diamond exerts pressure on the rubber layer under the action of air pressure, the pattern at the edge of the single crystal diamond is deformed, and when the position of the deformed pattern meets the standard, the single crystal diamond is cracked.

[0020] By adopting the technical scheme, the single crystal diamond exerts pressure on the rubber layer, so the pattern at the edge is deformed, and the position of the deformed pattern is judged, and if it meets the standard, it indicates that the position and size of the single crystal diamond meet the requirements.

[0021] The application can be further configured in a preferred example that after the cracking is completed, blowing is performed through the negative pressure hole, an air film is formed between the single crystal diamond and the rubber pad, and then the single crystal diamond is transferred.

[0022] By adopting the technical scheme, the existence of the air film reduces the difficulty of taking the single crystal diamond. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a schematic diagram of a modified layer structure of the application.

[0024] Figure 2is a schematic view of an overhead structure of a bearing table of the present application.

[0025] Reference numerals: 1, modification layer; 2, bearing table; 21, negative pressure hole; 22, texture. DETAILED DESCRIPTION

[0026] The present application is further described in detail below with reference to the accompanying drawings.

[0027] Reference Figure 1 and Figure 2 A method for separating a single crystal diamond disclosed in the present application forms a plurality of modification layers 1 on the single crystal diamond by a picosecond laser, and then separates the single crystal diamond along the modification layers 1 by a cleaving machine.

[0028] The picosecond laser is a 1064 laser source with a pulse width less than 15 picoseconds, a 50 times cutting objective, a frequency of 100 KHz, a laser energy of 1 W, and a processing speed of 200 mm / s.

[0029] When forming the modification layers 1, the laser forms the modification layers 1 inside the single crystal diamond in a direction perpendicular to the surface of the single crystal diamond, the interlayer spacing of the modification layers 1 is 50 um, the layer power attenuation of the laser is 3%, and the number of processed layers is 10 layers.

[0030] The cleaving machine includes a bearing table 2, the bearing table 2 is provided with a rubber layer, the bearing table 2 is further provided with a negative pressure hole 21 penetrating through the rubber layer, and the rubber layer is further provided with a radial texture 22, an extension line of the radial texture 22 passes through the center of the negative pressure hole 21. The texture 22 is in a groove shape and communicates with the negative pressure hole 21, when the single crystal diamond is placed on the bearing table 2, the single crystal diamond covers the negative pressure hole 21 and does not completely cover the texture 22.

[0031] When the single crystal diamond is placed on the bearing table 2, suction is performed through the negative pressure hole 21, under the action of air pressure, the single crystal diamond exerts pressure on the rubber layer, so that the texture 22 at the edge of the single crystal diamond deforms, when the position of the deformed texture 22 meets the standard, the single crystal diamond is cleaved. After cleaving, blowing is performed through the negative pressure hole 21, an air film is formed between the single crystal diamond and the rubber pad, and then the single crystal diamond is transferred.

[0032] When there is no deformed position of the texture 22, it indicates that the negative pressure is not enough or the single crystal diamond does not completely cover the negative pressure hole 21.

[0033] The implementation principle of the embodiment is that a picosecond laser source is used in cooperation with a 50 times cutting objective, under the action of the 50 times cutting objective, the ultrashort pulse laser beam is highly focused and compressed in the space near the focal point, the material in the focal point region absorbs the high peak power of the laser, the multiphoton absorption effect occurs, the electrons are excited from the material to form free electrons, and then the molecular bonds or atomic bonds of the material combination are directly destroyed due to the Coulomb repulsion, the single crystal structure of the material shrinks, the crystal changes produce micro explosion points, the laser focal point moves at a high speed in the sample, forms continuous and equally spaced cracks, and then forms a modified layer 1 with a certain depth.

[0034] The embodiments of the specific implementation are the preferred embodiments of the application, and do not limit the protection scope of the application, so: any equivalent changes made according to the structure, shape, principle of the application should be covered within the protection scope of the application.

Claims

1. A method of laser separating a diamond single crystal, characterized by: A modified layer is formed on a single crystal diamond by a picosecond laser, and then the single crystal diamond is separated along the modified layer by a cleaving machine; the cleaving machine comprises a bearing table, a negative pressure hole is arranged on the bearing table, and the single crystal diamond covers the negative pressure hole when the single crystal diamond is placed on the bearing table; a rubber layer for contacting the single crystal diamond is further arranged on the bearing table, the negative pressure hole penetrates through the rubber layer, a texture is arranged on the rubber layer, the texture is in a groove shape, and the single crystal diamond does not completely cover the texture; after the single crystal diamond is placed on the bearing table, suction is performed through the negative pressure hole, the single crystal diamond exerts pressure on the rubber layer under the action of air pressure, the texture at the edge of the single crystal diamond is deformed, the single crystal diamond is cleaved when the position of the deformed texture meets a standard, air blowing is performed through the negative pressure hole after cleaving is completed, an air film is formed between the single crystal diamond and the rubber pad, and then the single crystal diamond is transferred.

2. The method of claim 1, wherein: The modified layer is multilayered.

3. The method of claim 1, wherein: The picosecond laser is a 1064 laser source with a pulse width less than 15 picoseconds.

4. The method of claim 1, wherein: The laser frequency is 100 KHz, the laser energy is 1 W, and the processing speed is 200 mm / s.

5. The method of claim 1, wherein: When the modified layer is formed, the laser forms the modified layer inside the single crystal diamond in a direction perpendicular to the surface of the single crystal diamond, the layer spacing of the modified layer is 50 um, the layer power attenuation of the laser is 3%, and the number of processed layers is 10 layers.

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