Defect-enhanced photoconductive response of silicon-implanted borosilicate glass

Abstract

The E' (delta)-defect-enhanced photoconductivity of a metal-semiconductor-metal photodetector (MSM-PD) made on Si-implanted borosilicate glass (BSO:Si+) substrate is reported. The dark current of as-implanted BSO:Si+ MSM-PD is only 0.1 nA at bias of 70 V. The photocurrent of as-implanted BSO:Si+ MSM-PD illuminated at 488 nm is 0.91 nA, corresponding to photoconductive gain of 9.1 dB. The E' (delta)-defects luminescent at 520 nm are activated after 2 h annealing, which enhances the photocurrent of BSO:Si+ MSM-PD by one order of magnitude. Optimized responsivity, noise equivalent power, and detectivity of BSO:Si+ MSM-PD are 4.0 muA/W, 1.2x10(-9) W/Hz(1/2), and 3.5x10(5) cm Hz(1/2)/W, respectively. The electron paramagnetic resonance and etching-dependent photocurrent analysis corroborate the E' (delta)-defect-related photoconductivity of the BSO:Si+ glass. (C) 2004 American Institute of Physics.