Fig. 2
a Photoresponsivity with different annealing temperature for each sample is 30 min. b Photoresponsivity with different laser fluence. c Quantum efficiency depends on the wavelength for the APD that includes the micro-structured and unstructured regions. d The current-voltage characteristics of a 100-μm-diameter micro-structured black silicon photodetector [12]. e Current noise power density versus photocurrent under applied reverse bias voltage of 3 V. f Responsivity for a 250-μm-diameter black silicon device under applied reverse bias of 0, 1, 2, and 3 V [12]