Novel MIS Ge-Si quantum-dot infrared photodetectors

The metal-insulator-semiconductor (MIS) Ge-Si quantum-dot infrared photodetectors (QDIPs) are successfully demonstrated. Using oxynitride as gate dielectric instead of oxide, the operating temperature reaches 140 and 200 K for 3-10 and 2-3 μm detection, respectively. From the photoluminescence spectrum, the quantum-dot structures are responsible for the 2-3 μm response with high operation temperature, and the wetting layer structures may be responsible for the 3-10 μm response. This novel MIS Ge-Si QDIP can increase the functionality of Si chip such as noncontact temperature sensing and is compatible with ultra-large scale integration technology.