| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor device and its manufacturing method in which a stable constant voltage can be obtained without adding any steps and without affecting characteristics from an oxide film formed on pn bonding. <P>SOLUTION: On the surface of a semiconductor layer of one conduction type, the second semiconductor layer of an inverse conduction type, and the first semiconductor layer of an inverse conduction type of which an impurity concentration is lower than that of the second semiconductor layer, are provided so that their side faces overlap each other while surrounding the outer periphery of the second semiconductor layer of the inverse conduction type. On surfaces of the first semiconductor layer and the second semiconductor layer, a third semiconductor layer of one conduction type, and a fourth semiconductor layer of one conduction type of which an impurity concentration is lower than that of the third semiconductor layer, are provided with its side face brought into contact outside the third semiconductor layer. A Zener diode is formed by pn bonding with the second semiconductor layer on a bottom of the third semiconductor layer, and one terminal of the Zener diode connected to the second semiconductor layer is provided on the surface of the first semiconductor layer. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
