The effect of Ge-composition on the transit-time limited frequency response of a vertical Si/Si1-yGey P-i-N photodetector has been investigated. The change in Ge-content (y) causes the changes in properties of the SiGe layer and the Si/SiGe interfaces and, hence, affects the transit time of carriers in the Si/SiGe photodetector. The results obtained from the analysis show that at low bias, the bandwidth of the photodetector initially increases with increase in Ge-content, but after an optimum value of Ge-content, the bandwidth starts decreasing. This optimum value increases with increase in applied bias.
Mukul K. Das,
N. R. Das,
"Effect of Ge-composition on the frequency response of a Si/Si1-yGey P-i-N photodetector," Optical Engineering 45(12), 124001 (1 December 2006). https://doi.org/10.1117/1.2403869