Patent ID: 8017981
Filing Date: 2011-09-13
Classification: H01L,H03K

Abstract:
1. A semiconductor device made by a method comprising: positioning a first mask on a first layer of n-type semiconductor material, wherein the first layer is on a substrate; using the first mask, selectively implanting p-type dopants in the first layer of n-type semiconductor material to form a p-type implanted region adjacent a non-implanted region in the first layer; removing the first mask; epitaxially growing a third layer of n-type semiconductor material on the first layer; epitaxially growing a fourth layer of n-type semiconductor type material on the third layer; positioning a second mask on the fourth layer; selectively etching through the fourth layer to expose underlying third layer through openings in the second mask thereby forming raised features of n-type semiconductor material over the p-type implanted region of the first layer and one or more raised features of n-type semiconductor material over the non-implanted region of the first layer; removing the second mask; positioning a third mask which masks the raised features and the area between the raised features over the p-type implanted region of the first layer and which masks the raised feature over the non-implanted region of the first layer; using the third mask, selectively etching through the third layer to expose p-type implanted and non-implanted regions of the underlying first layer thereby forming first and second raised structures, the first raised structure comprising the raised features over the p-type implanted region of the first layer and the region of the third layer therebetween and the second raised structure comprising the raised feature over the non-implanted region of the first layer, the second raised structure having sidewalls; removing the third mask; forming ohmic contacts on exposed surfaces of the raised features of n-type semiconductor material and on the exposed p-type implanted region of the first layer; and forming Schottky contacts on the third layer between the raised features over the p-type implanted region, on the non-implanted portion of the first layer adjacent the second raised structure and on material of the third layer on the sidewalls of the second raised structure.