Excess noise measurement in avalanche photodiodes using a transimpedance amplifier front-end

Abstract

We report a versatile system for measuring excess noise and multiplication in avalanche photodiodes, using a transimpedance amplifier front-end and based on phase-sensitive detection, which permits accurate measurement in the presence of a high dark current. The system, which we have used successfully on a wide variety of materials and device structures, can measure reliably the excess noise factor of devices with a capacitance of up to ∼50 pF.

Avalanche Photodiodes in High-Speed Receiver Systems

“…The system after Li (Lau et al, 2006, Li, 1999) is superior in noise performance to prior reported systems. The transimpedance amplifier provides a signal to noise ratio which is superior to that possible in a 50Ω system.…”

“…The Xie et al (1993) system represents both. Bulman (1983), Ando and Kanbe (1981) and Lau et al (2006) presented systems based on phase sensitive detection. Xie et al (1993) and Toivonen et al (1992) used a DC approach.…”

“…The measurement is made using a CW light source and a noise figure meter such as the Hewlett Packard 8970A. The system has two significant advantages over PSD systems such as those of Bulman (1983) and Li (Lau et al, 2006). Several measurement frequencies are available up to the limit of the circuits or analyser.…”

“…For example the lowest practically measurable photogenerated noise is higher in CW systems than in some PSD systems. Using a transimpedance amplifier, Li (Li, 1999 has shown that the transimpedance amplifier reported by Lau et al (2006) can be used as the basis of a noise measuring system with greater (less negative) noise signal to noise ratio than is possible by using a 50Ω measurement system. A further objection to CW systems is that the noise without illumination -the dark noise -should be periodically measured in order to maintain consistency.…”

“…The system of Li (Lau et al, 2006, Li, 1999 employs phase sensitive detection and a transimpedance amplifier. A schematic diagram is shown in Figure 5.…”