We report a detailed procedure of using the anodic oxidation to passivate the SiGe film surface in order to enhance the functionality Si/SiGe heterojunction infrared metal-semiconductor-metal (MSM) photodetectors. Specifically, we seek to reduce the magnitude of the dark current while simultaneously boosting the photocurrent to dark current contrast ratio of MSM devices. Our study demonstrated that the current ratio was boosted by more than tenfold compared to that of the device capped with photo-chemical vapor deposited oxide. In addition, a sizable reduction in dark current (more than 3 to 5 orders of magnitude) was achieved for samples prepared at lower current densities compared to that of a sample without being treated with anodic oxidation.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)