Thermal damage in InSb (PV) detector induced by CW laser

A physical model of InSb (PV) detector irradiated by CW laser was established. The distribution of temperature was studied by Gaussian beam with 2-D thermal model. The relationship between the temperature transformation and irradiation time was obtained. By numerical method, it was found that the damage of InSb material irradiated by CW laser was melt, and it took place firstly at the center of the laser-facing surface. The higher the laser power was, the less damage time was needed. With the same laser power density, thinner sub needed less irradiation time. For a definite sub, the damage threshold of laser was higher than a certain I_min. Whereas I_min was higher for thinner sub. To improve the anti-irradiation ability, it was necessary to diminish the thickness of sub. Additionally, the calculation times of melt damage by 10.6 μm laser irradiation of different power were 1.57 s and 4.54 s, corresponding to the experimental data of 2 s and 4-5 s.