飞秒激光微构造硅光电二极管的光电响应

摘要

We investigated responsivity of photodiodes fabricated with silicon that was microstructured by femtosecond-laser pulses in a sulfur-containing atmosphere.In different temperature annealing,the aluminum electrodes were prepared using the e-lectron evaporation method according to different spike height of microstructured silicon.The femtosecond laser microstructured photodiodes were made,and the opto-electronic responsivities of photodiodes was measured.Test results show that the responsiv-ity of photodiodes depends on the height of spikes and annealing temperature,the responsivity can be as high as 0.55 A/W.For wavelengths of 1 100 nm below the bandgap we obtained responsivities about 0.4 A/W,which is higher than that for standard sili-con photodiodes.%在一定条件 SF6气体氛围中，硅可在飞秒激光辐照区产生μm 量级的尖峰结构。针对不同尖峰高度的微构造硅，在不同温度下退火，采用电子蒸发的方法在正反面分别镀上铝电极，制备出了飞秒激光微构造光电二极管，并测试了其光电响应。实验结果表明：飞秒激光微构造光电二极管的响应随微构造硅光电二极管的尖峰高度和退火温度的不同而不同。尖峰高度为3~4μm 的样品在973 K 温度退火30 min 后，响应度可达0.55 A/W。即使在1100 nm 波长处，这种新型的硅光电二极管的响应仍可高达0.4 A/W。