Resonator fabrication for cavity enhanced, tunable Si/Ge quantum cascade detectors

The detectivity of tunable SiGe quantum cascade injector structures designed for detection in the mid-infrared (MIR) spectra region, can be switched between two bands centered around 6 and View the MathML source by reversing the sign of the externally applied bias voltage. In order to enhance detectivity of these devices and restrict the response to narrower spectral bands, a process for integrating them into a vertical resonator cavity has been developed. The process is based on a low temperature View the MathML source etch mask deposition and, therefore, is applicable for these novel Quantum Well Infrared Photodetector (QWIP) structures grown by low temperature Si MBE.