The Study On Noise Measurement System And Technique Based On Lock-in Amplifier

The noise inside the electronic devices (especially the low-frequency noise such as1/f noise) is the key factor limiting the sensitivity and precision of the devices. And atthe same time, it is the important sensitive parameter to characterize the quality andreliability of the devices. Reliability of electric devices is closely related to thelow-frequency noise. Noise measurement can evaluate the quality and reliability of thedevices. Up to now, the field of low frequency noise is a very activity field. There arealso many problems to be solved. Such as: the measurement of low impedance and theelectron device that have complex circuit.On the carefulness study of measurement technique of low frequency noise, basedon our laboratory condition, I built up a noise measurement system based on lock-inamplifier. Further more, this lock-in amplifier system was tested and applied. Noise dataof thick film resistor sample and AI interconnect sample is acquired based on this noisemeasurement system. Comparison between data acquired by new system and dataacquired by old system was carried through and I chiefly give such content as1. Analyzing the measurement of low frequency noise of electron devicessystemically.2. Basing on my own experimentation and noise measurement theory, I gavesome experimental technology of noise measurement.3. Giving a 5- port AC bridge method based on lock-in amplifier which canrestrain background noise of PARC113.4. Successfully building up a noise measurement system based on lock-inamplifier which improved measurement precision and successfully separateout the contribution of the background to the measured noise. This system canmeasurement metal film resistor of 10Ω. There will be significance on noisemeasurement in low impedance devices.