Thermal Annealing Study On InGaAs/GaAs Quantum Dot Infrared Photodetectors

In this work, rapid thermal annealing was performed on InGaAs/GaAs quantum dot infrared photodetectors (QDIPs) at different temperatures. The photoluminescence showed a blue-shifted wavelength and the spectral response exhibited red-shift from the annealed QDIPs in comparison with the as-grown sample. The overall device performance was not affected by low annealing temperature however for high annealing temperature, some degradation in device detectivity (but not responsivity) was observed. This is a consequence of increased dark current due to defect formation and increased ground state energy.