GROUP-III-NITRIDE BASED LAYER STRUCTURE AND SEMICONDUCTOR DEVICE

摘要

A group-lll-nitride based layer sequence fabricated by means of an epitaxial process on a silicon substrate, the layer sequence comprising: at least one doped first group-lll-nitride layer (105) having a dopant concentration larger than 1x1018 cm-3; a second group-lll-nitride layer (106) having a thickness of at least 50 nm and an n-type or p-type dopant concentration of less than 5x1018 cm-3; and an active region made of a group-lll-nitride semiconductor material; wherein the first group-lll-nitride layer comprises at least one n-type dopant selected from the group of elements formed by germanium, tin, lead, oxygen, sulphur, selenium and tellurium or a at least one p-type dopant; and wherein the active region has a volume density of either screw-type or edge type dislocations below 5x109 cm-3.