Avalanche photodiode excessive noise factor measuring system

Abstract

The invention discloses an avalanche photodiode (APD) excessive noise factor measuring system, and relates to the test technical field of a semiconductor photoelectronic device. The APD excessive noise factor measuring system comprises a light source, an optical coupling assembly and a detection unit, wherein the detection unit comprises a chip test tool fixture, a polarization device, a number source list, an amplifier and a noise power test device. The light source is illuminated on a to-be-tested APD sample through the optical coupling assembly. The sample APD is connected with the polarization device through a test probe clamp. The number source list is connected with the direct current port of the polarization device. An interchange port of the polarization device is connected with an input end of the amplifier. The noise power test device is connected with an output end of the amplifier. According to the APD excessive noise factor measuring system, excessive noise factors of the APD are rapidly and accurately obtained in an in-time mode through simultaneous measurement of APD noise power and gain.

Description

technical field [0001] The invention relates to the technical field of testing semiconductor optoelectronic devices, in particular to a measurement system for measuring the excess noise factor of an avalanche photodiode. Background technique [0002] Excess noise factor is an important parameter to characterize the performance of Avalanche Photo Diode (APD). Different from ordinary PIN detectors, the photo-generated carriers of APD avalanche photodiodes undergo collision ionization under high electric field to generate offspring carriers, and the final output photocurrent is amplified by M compared with the initial injected photo-generated current (APD gain) times, this is the avalanche multiplication effect. This internal gain improves the sensitivity and signal-to-noise ratio of the APD, making it more and more important in high-speed long-distance optical communication systems. [0003] However, collision ionization is a random process, and the possibility of collision ...

AI Technical Summary

Problems solved by technology

[0006] In the phase-sensitive detection method, the system includes a lock-in amplifier and a transimpedance amplifier, which can simultaneously measure gain and noise. The sensitivity is relatively high, but the measurement frequency points are relatively small and time-consuming

[0007] In the direct power measurement method, the noise power meter is used to directly measure the noise power, and there are many frequency points that can be measured, but the gain and noise cannot be measured simultaneously, and the IV characteristics need to be tested separately. The real-time performance is not strong, and there are systematic errors.

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