| 摘要 |
PURPOSE:To decide the evaluation of a protective film of a semiconductor element in a short time under the condition of real use time, by conducting repeatedly a thermal shock test to a resin sealed semiconductor element and detecting and evaluating the protective film by dissolving sealed resin. CONSTITUTION:A thermal shock test is conducted by carrying out a cyclic movement of 50 and 100 cycles, etc. by which a semiconductor element sealed by a sealing resin 1 moves between 150 deg. and -65 deg. liquid phases at every five min. Hereafter, the resin 1 is dissolved by using fuming nitric acid and Al or Si in a wiring layer 3, an Si substrate 4 and a lead frame 5 under a protective film 2, are dissolved by immersing in KOH solution for ten min to detect the crack and pinhole of the film 2. Abnormality of the film 2 having from the beginning is enlarged by the cycle of the thermal shock, because the coefficients of thermal expansion of each constituting substance of the semiconductor element are different and the evaluation decision of the protective film is made possible in a short time. |
