Electrically insulating silicon carbide sintered body

Abstract

A silicon carbide sintered body comprising silicon carbide as principal constituent, a first component for providing electrical insulating properties to said silicon carbide, said first component comprising at least one of metallic beryllium, beryllium compounds, boron and boron compounds and contained in a total amount of 0.01 to 3.5% by weight calculated as metal, and a second component which can further promote said silicon carbide sinterability provided by said first component and which does not diffuse easily in the particles of said silicon carbide, said second component comprising at least one substance selected from the Group I elements exclusive of hydrogen and francium, Group II elements exclusive of beryllium, radium and mercury, Group III elements exclusive of boron and aluminum, Group IV elements exclusive of carbon, Group V elements, Group VIa elements, Group VIIa elements Group VIII elements exclusive of iron, and compounds thereof, and contained in a total amount of 0.01 to 10% by weight, with the remainder substantially comprising silicon carbide. This silicon carbide sintered body has an electrical resistivity of 10.sup.7 .OMEGA..cm or above at room temperature and is also excellent in electrical insulating properties and can be advantageously used as substrates for semiconductor devices, etc.