Method for Detecting GaAs Die Fractures in Device Manufacturing Through the of a Designed Test Vehicle

摘要

Substrate fracture is a common failure mechanism for GaAs products. In most cases, fractures can be detected and rejected by electrical final test. At a low occurrence rate, however, some fractures can go undetected. The fractures may not cross a circuit component in which case the electrical circuit is not disrupted or the circuit metallization may not fracture with the GaAs. A test structure was designed and implemented on a dedicated test vehicle to detect fractures even at a low occurrence rate. The test vehicle makes use of a thin, brittle metal line patterned in a serpentine fashion over the surface of the die. The metal line is electrically testable with a simple resistance measurement so large quantities of devices can be tested in order to produce a suitable sample population. By using the test vehicle, the manufacturing process can be monitored and fracture-causing processes can be improved.