DETECTING DEVICE FOR DETECTING SEMICONDUCTOR PELLET

摘要

PURPOSE:To detect reliably defective semiconductor pellets due to a break and so forth by a detecting device in the simple constitution by a method wherein an He-Ne laser beam is irradiated on the semiconductor pellets through a diaphragm, its reflected light is detected in the light-receiving element, the current value of its output is compared with the current setpoint and whether the pellets are defective or non-defective is decided. CONSTITUTION:A laser beam from an He-Ne laser light source 1 is narrowed by a pinhole plate 4 via a filter 2 and a reflecting mirror 3 and the laser beam is irradiated on the semiconductor pellets of a wafer 5 on an X-Y stage 10. The reflected light is made to incide in a light-receiving element 7. The current value of its output is compared with the prescribed current setpoint in the light-receiving element 7 and when the current value of the output is lower than the setpoint, it is decided that defects such as a break and so forth exist on the pellet. Accordingly, defective pellets due to a break and so forth are detected by the detecting device in the simple constitution with a high reliability.