Method for judging IDDQ test by using current difference value

Abstract

The invention discloses a method for judging the IDDQ test result by using the current difference value delta IDDQ (MAX(IDDQ_1, IDDQ_N)-MIN(IDDQ_1, IDDQ_N)) and using the result for improving the IDDQfault and the bridging fault test coverage rate. By using the method, the existing method of judging the IDDQ only by using two test points can be improved, and the test points are widened to any onetest point. Through the additional addition of the test points, the test coverage rate of the IDDQ test can be improved. Meanwhile, a current difference value is used as the basis for judging the IDDQ test; the defect of heavy background current under the deep sub-micron process conditions through the single judging of the current intensity during the IDDQ test can be reduced. The stable mass production during the chip mass production under the background of process deviation existence can be further ensured.

Description

technical field [0001] The invention belongs to the field of screening and testing of integrated circuit chips. By judging the leakage changes of the digital part of the chip in different states, the IDDQ fault and bridging fault of the chip are detected, thereby improving the screening test coverage. Background technique [0002] As the market's demand for the quality of semiconductor products increases, the industry needs to improve the test coverage in the screening test field. Especially for the high-reliability market (vehicle grade products), standards (such as AECQ100) clearly hope to introduce IDDQ testing. However, with the progress of the process size, the static power consumption of the chip has been increasing. The current during the pure IDDQ test is getting larger and larger with the progress of the process, but the current caused by the fault changes very little. In the mass production stage, the processing technology There will be deviations, and the curren...

AI Technical Summary

Problems solved by technology

However, with the progress of the process size, the static power consumption of the chip has been increasing. The current during the pure IDDQ test is getting larger and larger with the progress of the process, but the current caused by the fault changes very little. In the mass production stage, the processing technology There will be deviations, and the current variation between batches introduced by process deviations is already greater than the current changes caused by faults. Therefore, in the context of continuous technological progress, the testing capability of IDDQ is getting worse and worse.

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