Nonlinearities of the responsivity of various types of silicon photodetectors have been studied. These detectors are based on photodiodes with two sizes of the active area (10 × 10 mm2 and 18 × 18 mm2). The detector configurations investigated include single photodiodes, two reflection trap detectors, and a transmission trap detector. For all devices, the measured nonlinearity was less than 2 × 10-4 for photocurrents up to 200 μA. The diameter of the measurement beam was found to have an effect on the nonlinearity. The measured nonlinearity of the trap detectors depends on the polarization state of the incident beam. The responsivity of the photodetectors consisting of the large-area photodiodes reached saturation at higher photocurrent values compared with the devices based on the photodiodes with smaller active area.
© 1998 Optical Society of America
Original Manuscript: October 3, 1997
Revised Manuscript: January 12, 1998
Published: May 1, 1998
Toomas Kübarsepp, Atte Haapalinna, Petri Kärhä, and Erkki Ikonen, "Nonlinearity measurements of silicon photodetectors," Appl. Opt. 37, 2716-2722 (1998)