Tuning of detection wavelength of quantum-well infrared photodetectors by quantum-well intermixing

Proton implantation followed by rapid thermal annealing was used to tune the spectral response of the quantum-well infrared photodetectors (QWIPs). Various implantation schemes, such as single low energy implantation, multiple energy implantation, and single high energy implantation were compared for tuning the wavelength of QWIPs. Large redshift of the QWIPs' response wavelength with either narrowed or broadened spectrum was obtained after interdiffusion. Comparatively, the single high energy scheme is the simplest and most effective method. Furthermore, by applying a two-step implant-anneal sequence to single high energy implantation, the device wavelength was further shifted with improved photocurrent signal, making it promising to achieve the fabrication of multi-color detectors.