A transimpedance amplifier for excess noise measurements of high junction capacitance avalanche photodiodes

Abstract

This paper reports a novel and versatile system for measuring excess noise and multiplication in avalanche photodiodes (APDs), using a bipolar junction transistor based transimpedance amplifier front-end and based on phase-sensitive detection, which permits accurate measurement in the presence of a high dark current. The system can reliably measure the excess noise factor of devices with capacitance up to 5 nF. This system has been used to measure thin, large area Si pin APDs and the resulting data are in good agreement with measurements of the same devices obtained from a different noise measurement system which will be reported separately.

A low noise op-amp transimpedance amplifier for LIDAR applications

“…Table I shows a comparison of signal-to-noise ratio (SNR) of published TIAs [3][4][5][6][7]. Lau et al [7] and Ando et al [5] show the best SNR and this work demonstrating similar SNR.…”

“…Signal-to-noise ratio of several TIAs is reported in [3]. For the signal-to-noise ratio calculations presented in [3], the signal is taken as full shot noise defined by 1 µA.…”

“…However, Lau et al [7] TIA has a smaller bandwidth compared to our TIA. The authors in [3] argue that no noise specifications are given for Ando and Kanbe TIA and that only the noise power available within a specific bandwidth is compared with the signal, which makes the value given in table I for SNR not suitable for comparison.…”

An excess noise measurement system for weak responsivity avalanche photodiodes

“…The systems used by Bulman and Ando & Kanbe [7,8] required minimum primary photocurrents of 0.63 µA and 6.25 µA respectively for their measurements. Lau et al [9] and Green et al [10] reported measurement systems based on transimpedance amplifier front-ends. Lau et al [9] reported that the excess noise factor could be measured on APDs with submicron depletion region widths, high dark currents, a capacitance of up to approximately 50 pF and required a minimum primary photocurrent of 0.22 µA.…”

“…The BPX65 is now replaced with the device under test (DUT). So the noise power of the DUT is, ) ( ) ( 2 2 M MF A C eIB N DUT eff DUT  (10) Where Beff(CDUT) is the effective noise bandwidth of the system when connected to the device under test, M is the corresponding multiplication and I is the multiplied photocurrent, I = IphM. Combining (9) and 10 Figure 8 shows the measurement of the minimum photocurrent required for a BPX65 to obtain a measurable noise power using this circuit.…”