Gaussian Pulsed Laser Etching of CVD Diamonds

Abstract

The Gaussian pulsed laser line etching energy density distribution model is constructed, and the effects of laser power and number of pulses on the point/line size of diamond surface produced by chemical vapor deposition (CVD) are studied. The diffusion mechanism of energy on material surfaces and the compositions of etched surfaces are obtained. On this basis, the laser surface etching is conducted. The results show that the etching profile is approximately a Gaussian one under the action of single Gaussian pulse, which indirectly proves that the energy of laser beam acting on the material surface shows a Gaussian distribution and the etching surface is composed of diamond, graphite and hybrid materials. Moreover, both the pulse point etching depth and width increase as laser power and number of pulses increase. The laser power has a great influence on the line etching degree of the CVD diamond surface. When the power value increases by 12 W, the etching width and side sweep depth increase by 23.32 μm and 346.04 μm, respectively. In contrast, the laser scanning speed has a relatively small influence on the line etching degree of the CVD diamond surface. When the scanning speed increases by 49.8 mm•s-1, the etching width and side sweep depth decrease by 6.35 μm and 70 μm, respectively. The etching results under the conditions of power of 3 W, scanning speed of 50 mm•s-1 and scanning spacing of 2 μm indicate that the etching depth is 9.71 μm and the surface roughness is 1.10 μm.