| 摘要 |
PURPOSE:To improve the reliability by forming a guard ring layer and a channel-stopper region in the same step, and forming the guard ring layer in a self-aligning type, thereby reducing a processing cost. CONSTITUTION:An Sb or As is selectively doped on a P-type single crystal silicon substrate 11 to form an N-type buried layer 12, an N-type silicon layer 13, a silicon oxide film 14 and a silicon nitride film 15 are sequentially formed, and the films 15, 14 except an element forming region are removed. With the film 15 as a mask the layer 13 is so etched as to taper the side, B ions are implanted and diffused to form a P-type diffused layer 17, oxidized to form a separate oxide film 18, thereby separating to a guard ring layer 171 and a channel-stopper region 172. The films 14, 15 are removed, a silicon oxide film 19 and a silicon nitride film 20 are sequentially formed, a hole is formed, a Pt film 21 is formed, and a Schottky contacting surface 22 and an ohmic contacting surface 23 are obtained. |
