Abstract: Quantum well infrared photodetectors (QWIPs) offer numerous potential applications for defense,industry,and medicine.A novel p-type tensile strained Si/SiGe QWIP is proposed in this paper.The valence band structure of the strained Si/SiGe quantum well and hole effective mass of the strained SiGe alloy are calculated using the k·p method.When tensile strain is induced in the quantum wells,the light-hole state with small effective mass becomes the ground state,which is expected to have lower dark current than n-type QWIPs and also have larger absorption coefficient and better transport characteristics than conventional unstrained or compressive strained p-type QWIPs.Designs for p-type tensile strained Si/SiGe QWIP based on the bound-to-quasi-bound transitions are also discussed.

Key words: tensile strained layer, Si/SiGe quantum well, infrared detector