| 摘要 |
PURPOSE:To enhance the voltage-resistant characteristics of an element by providing two mesa grooves having different depths and having a structure wherein the region of a depletion layer is more widely expanded then before when a forward voltage is applied. CONSTITUTION:A pn-junction 10' is cut out between the first mesa groove 20 and the second mesa groove 21. The pn-junction 10' is left beneath the first mesa groove 20. It is preferable that the width between the plane of the junction 10' and the central lower portion of the mesa groove 20 is thinner than the depletion layer which is yielded at the time of forward-voltage application, i.e., 30mum or less. The difference in levels of the mesa grooves are constituted by, for example, leaving an oxide film and the like which will serve as an etching mask in the mesa groove 20, and not providing such a mask in the mesa groove 21, and etching both grooves at the same time. |
