IMPROVEMENT OF INITIAL TROUBLE WITH A CERTAIN PRODUCT GROUP OF PRODUCTION PROCESSES

Electronic components that are on the boundaries of acceptable quality often experience unstable states, which may cause abnormal behavior in equipment. For example, this product seems to be distinctive when parts susceptible to 1/f noise are used. When multiple noise-sensitive parts are used, an abnormality appears due to the infuence of the external environment, which is high temperature and humidity in Japan. Many abnormalities are found when multiple 1/f noise-sensitive parts are used. However, no abnormality is found when these noise-sensitive parts are removed from the device. The rate of quality defects in the parts examined in this study is about 3%. To ensure high manufacturing quality, it is essential that engineers are able to mathematically model and predict this phenomenon. We introduced a potential function with the quality boundary width as a variable and we assumed that the width changes stochastically. We also improved component quality using Ginzburg and Landau (GL) free energy to model the quality boundary region and by evaluating the potential function. As a result, we were able to reduce the probability of quality abnormality from 3% to 0.5%