Photoluminescence characterization in GaAs/AlGaAs quantum well infrared photodetectors

Micro-photoluminescence (mu -PL) measurement was performed on GaAs/AlGaAs q uantum well infrared photodetectors (QWIPs). The PL peaks in the multi-quan tum wells (MQWs), which reveal the energy positions of band-to-band transit ions in the barrier and the welI, respectively, are directly related to the Al component in the barrier of AlxGa1-xAs. Using standard effective mass t heory for quantum wells the realistic Al component x and well width d were deduced. Consequently the peak response wavelength lambda (p) the QWIP was determined. The calculated lambda (p) is coincident with the result from ph otocurrent spectrum for the same sample very well. It proves that the prese nt method is very applicable for the MQW materials control in the process o f device fabrication.