SEMICONDUCTOR DEVICE, SEMICONDUCTOR WAFER, AND MANUFACTURE OF SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor device and semiconductor wafer, whereby function tests can be accurately made in a wafer state and provide a semiconductor device which provides an accurate output. SOLUTION: A field oxide film 97 is made so as to cover a scribing region 80 whereby the thick field oxide film 97 prevents a light P from penetrating from the top face of a wafer 72 into the scribing region 80. As a result, if a P-N junction is formed at the scribing region 80, no photocurrent flows in the P-N junction and hence the photocurrent flowing in a phototransistor adjacent to the scribing region 80 can be accurately measured, i.e., the function tests can be accurately conducted in a wafer state. Even in a semiconductor device mounting a phototransistor PT obtd. by cutting the scribing region 80, an accurate output corresponding to the light P can be obtd.