硅光电探测器光谱量子效率的测定

Determination of Spectral Quantum Efficiency of Silicon Photodetector

光电探测器量子效率的准确测定对光辐射计量具有重要意义。基于低温辐射计,在氦氖、氩氪离子以及钛蓝宝石激光器的10个波长上测量了无窗型硅光电探测器的外量子效率。根据光电探测器表面反射比和二氧化硅层厚度的关系,基于在3个激光波长上光电探测器表面反射比的测量结果,通过最小二乘法得到光电探测器表面二氧化硅层的厚度,并由此得到光电探测器表面的光谱反射比。根据表面反射比和激光波长上探测器外量子效率结果得到相应波长的内量子效率。进行了光谱量子效率拟合。在488～900nm光谱范围内量子效率模型拟合结果与在相应激光波长上测定的量子效率结果的偏差在1.5×10-4之内。

The determination of quantum efficiency of a photodetector is of great importance in radiometry. External quantum efficiency of windowless silicon photodetectors is measured with cryogenic radiometer at ten wavelengths of He-Ne, Ar＋-Kr＋ and Tisapphire lasers. Based upon measured reflectance at three laser wavelengths, the thickness of the silicon dioxide layer is obtained through least square method according to the relation between surface reflectance of a photodetector and the thickness of its silicon dioxide layer. Spectral reflectance of the photodetector surface is thereby obtained. Internal quantum efficiency is calculated from surface reflectance and external quantum efficiency result at the laser wavelengths, and spectral quantum efficiency is fitted. The deviation of modeled result from experimental result is within 1.5×10-4 in the spectral range from 488 to 900 nm.