| 摘要 |
PURPOSE:To sort the semiconductor parts according to the changing rate of luminescence of the parts by a method wherein specified first-third laser beam is applied in order to the parts, respective luminescence at the time of the first, the third laser beam irradiation is detected, and the changing rate of luminescence is calculated using a specified equation. CONSTITUTION:The first-third laser beam phi1, phi2, phi3 of an He-Ne laser, etc. are applied successively to the semiconductor parts of a semiconductor laser, etc., The beam phi2 is made to have the larger intensity of light than the beam phi1, and the beam phi3 is made to have the same intensity of light with the beam phi1. The first luminescence P1 generated from the semiconductor parts by the application of the beam phi1 and the luminescence P3 generated by the application of the beam phi3 are detected with a photodetector. The changing rate of luminescence DELTAP/P1 is calculated with the obtained values of luminescence P1, P3 according to the equation DELTAP/ P1=(P1-P3)/P1 using a microcomputer, etc., to sort the parts automatically. By this way, when a defect, i.e., a defect including the dislocation is in the nature of crystal, the defect propagates being damaged by the laser irradiation of beam phi2, therefore the luminescence P3 due to the beam phi3 is eliminated and the sorting is simplified. |
