| 摘要 |
PURPOSE:To reextend the lifetime of the subject semiconductor element by a method wherein a P is injected through the thin heat oxidation film or a polycrystalline Si film on an Si substrate having a P-N junction and then a heat treatment is performed in the atmosphere containing the P. CONSTITUTION:P layers 12 and 13 are provided on an N type Si substrate 1 by diffusing a Ga and a PSG14 s formed on the layer 13 by coating an SiO2 on the layer 12. At this time, a heavy metal inside and outside of the substrate 11 is absorbed by a PSG14 and its lifetime is sharply increased, and the heavy metal absorbed on the surface of the Si substrate during the formation of the N layer 15 by the following P diffusion at a high-temperature, is diffused again. Then, when a heat oxidation film or a polycrystalline film 48 having the thickness which penetrates the P and does not let it diffused, is laminated on the layer 12 and a treatment is performed in the atmosphere containing the P at the temperature of approximately 1,000 deg.C, the lifetime once reduced by the formation of the layer 15 is increased again. It is good to protect the layer 15 by providing an SiO2 26 and the like. When the Au is diffused on the side of the P layer 12 and an electrode is lastly attached above the layers 12 and 15, an SCR having a carrier of a long life and excellent characteristics can be obtained. |
