长脉冲致硅基 QPD损伤面积及形貌实验研究

为了研究硅基QPD在不同能量密度、不同脉宽激光辐照下的损伤面积、形貌，基于二维显微测量技术，测量了硅基QPD单一象限的损伤面积、形貌随激光能量密度和脉宽的变化。结果表明，在毫秒脉冲激光作用下，硅基QPD产生表面剥落、褶皱、裂纹、熔坑等损伤效果，且主要受入射激光功率密度影响，损伤面积随激光能量密度逐渐增加，随脉宽增加逐渐降低。通过实测分析，得出了不同激光脉宽下，硅基QPD表面形貌损伤阈值。激光脉宽为0.5 ms，能量密度为15.79 J/cm2时，硅基QPD出现熔融损伤；而脉宽为1.0、1.5、2.0、3.0 ms时，硅基QPD出现表面剥落的能量密度值为14.12、33.94、39.76、47.62 J/cm2。

Experimental study on damage area and morphology of silica-based QPD induced by long pulse

Based on two-dimensional metallographic microscopic measurement technology, the damage area and morphology of the silicon-based quadrant photo-detector(QPD) were studied under different laser energy fluences and pulse widths. The damage area and morphology of silicon-based QPD with single cell change with laser energy fluences and pulse width were measured. The results showed that, the QPD produced surface pooling, folding, cracks, ablation areas and other damage effects under the action of a millisecond pulse laser. The damage area mainly affected by the incident laser energy fluences, and the damage area gradually increased with the laser energy fluences and decreased with the increase of pulse width. The damage thresholds of a silicon-based QPD with different laser pulse widths were obtained. At 0.5 ms, and the energy fluences was 15.79 J/cm2, the silicon-based QPD produced melting damage, and the energy fluences values of surface-damaged thresholds in the silicon-based QPD with pulse widths of 1.0, 1.5, 2.0 and 3.0 ms are 14.12 J/cm2, 33.94 J/cm2, 39.76 J/cm2 and 47.62 J/cm2.