Semiconductor device manufactured by using a multilayer mask

Abstract

A semiconductor device contains first and second semiconductive regions (43 and 78) and first, second, and third semiconductive zones (59/61, 79, and 71) of opposite conductivity type to the regions. The first zone adjoins an insulating layer (45/46/47/48/63) along an upper surface of the first region. The second region extends to the upper surface through a window in the insulating layer. The second zone adjoins the second region below the window and is spaced apart from the third zone which extends to the upper surface. The zones and insulating layer upwardly and laterally enclose the second region. A first segment (59) of the first zone is continuous with the third zone and at least partly adjoins the lateral edge of the insulating layer located apart from the window. A second segment (61) of the first zone extends between the first segment and second zone, at least partly adjoins the lateral edge of the insulating layer located along the window, and has a much greater sheet resistance than the first segment.