Researches On The Measurement And Non-destructive Diagnostic Of Low Frequency Noise For Microwave Device

Microwave semiconductor devices and circuit feature with high speed, anti-radiation, wide operating temperature and low power, which made of compound semiconductor GaAs、InP and GaN. Thermal effect of device becomes increasingly obvious. with the device dimension into the sub-micron or deep sub-micron. Thus, the research of performance on microwave device at thermal stress is important. Recently. low frequency noise measurement technology (LFN) is an evaluation tool for representing the devices’reliability and performance, it can be used to detect defects of the devices, and low cost, without any damage. A new method of diagnosing the damage of thermal stress on microwave device and circuit with LFN measurement technology is studied in this paper.Firstly, based upon a familiar structure and performance of PHEMT. a plan for measuring noise is made, which contains the choice of amplifier, design of bias circuit and establishing of noise test system. And then, the noise and electrical properties of microwave device are measured before and after high temperature stress. On the basis of the experimental results, degradation mechanism of device electrical parameters is analyzed, the reason of causing the noise is interpreted, and the noise characterization model of the thermal damage model of microwave device is proposed. In order to determine the location of g-r noise, measure the low frequency noise when the device is biased near pinch-off. Secondly, the noise test can be used to diagnose the damage of the microwave integrated circuits, which based on the noise of microwave discrete device. The noise of both the qualified and failure circuit is measured and analyzed, in the meantime, the noise parameters, which is related to circuit damage, are extracted. The analysis proved that noise measurement technology can be preliminarily used for the damage of microwave integrated circuit.