Anneal treatment to improve the performance of extended wavelength In0.83Ga0.17As photodetectors

For the purposes of improving the performance of the SWIR detector, two types of annealing treatment for extended wavelength In0.83Ga0.17As photodiodes with PIN structure are studied. In contrast to the sample A (rapid thermal annealing is performed after mesa etching for fabricating the In0.83Ga0.17As photodiodes), the sample B (rapid thermal annealing is performed before mesa etching for fabricating the In0.83Ga0.17As photodiodes) has a lower dark current at the same test temperature 220 K and 300 K, respectively. The different anneal treatment improves quality of the material by decreasing the defects of devices structure. The voltage-current curves have been used to measure the dark current of different devices. Plane-view electron beam induced current (PV-EBIC) and secondary electron (SE) images have been used to evaluate the performance correlated imperfection or defect features of In0.83Ga0.17As photodiodes structures and the defect density is 2.33 × 107 cm−2 for sample A, 8.14 × 106 cm−2 for sample B.