飞秒激光微构造硅二极管Ⅰ-Ⅴ特性研究

Study on Ⅰ- Ⅴ Characteristic of Femtosecond- laser Microstructured Silicon Photodiodes

在一定条件下SF6气体氛围中,硅可在飞秒激光辐照区产生微米量级的尖峰结构。退火后用ALD在微构造硅表面上沉积50nm的Zn O:Al电极,背面镀上Al电极形成二极管,测试二极管的光吸收特性及I-V特性。研究表明微构造硅二极管在宽波段范围内有明显增强的光吸收。在整个测量范围(250nm到2500nm)可以达到0.85以上,并且光吸收随着尖峰高度的增加而增加。通过测量微构造硅二极管的I-V特性曲线,发现微构造硅二极管存在良好的整流特性,可以广泛应用在光电探测和太阳电池等领域。

The surface microstructured silicon can be prepared by femtosecond laser pulses irradiation in SF6 in certain conditions. After annealing,Zn O： Al film of 50 nm was covered on microstructured silicon using ALD,Al electrode forming on the back of silicon,so the diode of microstructured silicon was made. The absorption characteristics and I- V characteristics of diode were tested. The research results showed that the microstructured silicon diodes have significantly enhanced light absorption in the wide band range. In the whole measuring range（ 250 nm to 2500 nm）,the absorptance can be above 0. 85,and the absorptance increases with the height of the peak. I- V characteristic curve showed that the microstructured silicon diode has good rectifying properties,and can be widely applied in the field of photoelectric detection and solar cells.