Automatic Verification of Mixed-Signal ATE Test Programs using Device Variation

Modern semiconductor mixed-signal products such as fully integrated circuits become more and more complex. This results in an increasing effort to develop the corresponding test programs for semiconductor test systems. Every implementation error in the test program could have a huge impact to the customer and must be avoided by all means. Therefore, the verification of the test program is an essential part of the development and the resulting effort has been increased significantly over the last years.Our methodology aims to formalize the test program verification, automate its execution, and evaluate the outcome. A high number of test sets containing multiple tests are created by using an approach based on mutation testing. Device responses provided to the test program are specified and the obtained results are compared against expected ones. Variants of correct and defective response sets can be emulated without the need for a physical or modeled device with the same characteristics. As the verification runs in tester offline mode, neither a semiconductor test system nor physical devices are required to run this approach.The concept is demonstrated by executing a given test program providing a special subset for device responses and assessing the obtained test program results.