Energy band design for p-type tensile strained Si/SiGe multi-quantum well infrared photodetector

The band structure of the confined states is calculated for Si/SiGe multi-quantum well infrared photodetector (M-QWIP). The influence of the Ge component in pseudosubstrate on the energy band structure of Si/Si{in0.54}Ge{in0.46} multi-quantum wells (MQWs) is investigated. It is found that the high energy levels in the MQWs move up while the low energy levels move down as the Ge component in pseudosubstrate increases. The influence of the barrier width on the energy band structure of MQWs is also studied based on the 6 × 6 k·p method. The results show that the Si barrier between 5 nm and 10 nm is optimized to enhance the intersubband absorption in the MQWs.