Method and device for testing reliability of nonvolatile memories

Abstract

The invention discloses a method for testing reliability of nonvolatile memories, which comprises the following steps: respectively selecting N blocks from each of K nonvolatile memories respectively provided with Nm blocks; respectively executing a test program for T times on the selected K*N blocks to acquire test data; according to the test data, counting a data relation between the frequency for executing the test program and the number of blocks accumulatively failing in tests in the frequency, and drawing a test curve; determining an equivalent failed block number judging standard; reading a failure number corresponding to an executing frequency value in the test curve; and comparing the obtained failure number with the equivalent failed block number judging standard, judging whether the nonvolatile memories are qualified. The invention also provides a device for testing the reliability of the nonvolatile memories. The test method and the test device have the advantages of reducing test time and improving test efficiency under the condition of not losing statistical significance.

Description

【Technical field】 [0001] The invention relates to the field of integrated circuit manufacturing and testing, in particular to a method and device for reliability testing of non-volatile memory. 【Background technique】 [0002] In the field of integrated circuit manufacturing, with the continuous reduction of the feature size of integrated circuits and the continuous improvement of chip integration, traditional production models, process materials, device models, and testing methods are facing many challenges. [0003] A non-volatile memory is a common semiconductor integrated circuit, and each non-volatile memory includes several blocks for storing data. Reliability testing for non-volatile memory is one of the most critical links in the manufacturing process. The purpose of the non-volatile memory reliability test is to investigate the reliability of several non-volatile memories in a certain batch, and judge the reliability of the non-volatile memory by calculating the pro...

AI Technical Summary

Problems solved by technology

[0005] At present, the application field of non-volatile memory usually requires the memory to have a storage life of at least tens of thousands of times. Therefore, in the reliability test, the number of times T of each block to execute the test program m Usually more than tens of thousands of times, and usually there are thousands of blocks in each non-volatile memory, that is, N m Usually above 1000, so the above test will consume a lot of test time

For example, for a standard 2Gbit capacity flash memory, each flash memory has 2000 blocks, and each block is executed 10 5 test program, in this case, a total of nearly a year was spent testing a single flash memory

Such a long test time is completely unacceptable for IC manufacturers

Simply reducing the test time by reducing the number of non-volatile memories used for testing or reducing the number of times the test program is executed will inevitably reduce the statistical significance of the test results and reduce the persuasiveness of the test results.

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