| 摘要 |
PURPOSE:To attain high detection accuracy by placing a mask plate having apertures on a lead frame where many molded semiconductor elements are formed, photosensors are provided to the upper and lower portions thereof, a dam portion of element is exposed within the aperture by moving the mask and detecting the sealing condition with the transmitting condition of light. CONSTITUTION:A lead frame 1 where many molded semiconductor elements are formed is provided on a frame loading material 35, a mask plate 30 having many apertures 31 is placed thereon, and the photosensors 40 are respectively provided to the upper and lower portions. The mask plate 30 is moved by a supporting member 32, a rod 33 and a cylinder 34, and the molded part 3 of element and dam portions 6 a nd 7 surrounding it are sequentially exposed within the aperture 31. Thereafter the dam portions 6 and 7 are irradiated with the light emitted from the light emitting part 40a of the photosensor 40. If the resin sealing part is defective herein, the light transmitting through it is detected by the sensor 40b and defective condition is confirmed. |
