Development of an information system for HGA performance tests

Abstract

This thesis is the development of an information system for tests of head gimbal bond assemblies in a hard disk manufacturing company and it is the key component of hard disk drive assembly. The research starts from analyzing the existing testing operations, its uses of information and the procedures of the test operators. Then a system is developed from the analysis of information requirements for the testing operation, especially the application of statistical methods to analyze the test results. The system replaces the existing lengthy report preparation procedure with automatic reporting. The analyses of the test results are, therefore, available to the test operators and other users in appropriate formats and time. In addition, the system uses the test results to monitor and analyze the test in real time so that it can trigger warning of problems from the production processor the testing process. Responses to problem are thus faster than the existing system, which often finds out about the problems long after they have occurred. In a trial implementation, the performance of testers is increased from 5,800 defective part per million (DPPM) per hour to 1,124 defectives part per million (DPPM) per hour and defects are reduced by 0.4 percent because of faster responses to problem in the production and the fast processes. The report preparation, which used to take four hours and used 13 men for the task, is eliminated by automatic reporting. In addition, users are quite satisfied with the designed preformatted reports.