Reverse bias test sample protection method and device

Abstract

The present invention relates to a reverse bias test sample protection method and device. The method provides a plurality of samples to be tested, a gate bias voltage circuit and a reverse bias voltage circuit. The device further comprises a fuse group and a low-voltage relay group, the fuse group comprises protection fuses having the same quantity as the samples to be tested, the low-voltage relay group comprises low-voltage relays having the same quantity as the samples to be tested, the first end of each sample to be tested is electrically connected with the gate bias voltage circuit, the second end of each sample to be tested is connected with the first end of a corresponding protection fuse in the fuse group and the first end of a normally open contact of a corresponding low-voltage relay in the low-voltage relay set, the second end of each fuse is electrically connected with the reverse bias voltage circuit, the second end of the normally open contact of each low-voltage relay isconnected with one end of the normally open contact of a high-voltage relay KM0, and the other end of the normally open contact of the high-voltage relay KM0 is earthed. The protection trigger current can be flexibly set to improve the response speed and protection accuracy of the protection motion.

Description

technical field [0001] The invention relates to a method and a device, in particular to a reverse bias test sample protection method and device, belonging to the technical field of reverse bias test protection. Background technique [0002] HTRB (High Temperature Reverse Bias, high temperature reverse bias test) is an accelerated life test. During the test, specific electrical conditions are applied to the sample to be tested, and then the sample is placed in a high temperature environment at a specific temperature (such as 125°C) for a specific time ( such as 1000 hours). By applying such harsh environment and electrical stress to the device to be tested to investigate whether the characteristics of the sample to be tested will be degraded, thereby judging or evaluating the quality of the sample to be tested. [0003] h 3 TRB (High Temperature High Humidity Reverse Bias, high temperature and high humidity reverse bias test) is an accelerated life test. During the test, sp...

AI Technical Summary

Problems solved by technology

[0011] 1) The sample suddenly breaks down and loses its withstand voltage capability;

[0012] 2) The withstand voltage capability of the sample degrades slowly and the leakage current gradually increases accordingly

[0018] 1) The consistency of the fusing current of the fuse is poor, which makes the current protection accuracy low (it is impossible to accurately control the level of leakage current to trigger the protection)

[0019] 2) The fusing current of fuses available on the market is usually much higher than the current level that the sample needs to trigger protection

[0020] 3) Fuses with smaller fusing current are often more expensive, resulting in higher testing costs

(The protection trigger current can be set to any value within the leakage current collection range); the disadvantage is that the price of the high-voltage relay is very high (usually several hundred yuan), and because the test system often has many test channels, the hardware cost of the entire system is relatively high high

[0026] Disadvantages of fuse protection: the current required to protect the sample is usually much lower than the current required for the fuse to blow

[0034] The price of high-voltage relays is very high (usually the price of each relay is several hundred yuan), and because the test system often has many test channels, the hardware cost of the entire system is relatively high

Due to the high hardware cost of each test channel, the test system using this protection scheme often has very few test channels

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