Method for manufacturing silicon carbide semiconductor device
AssigneesSumitomo Electric Industries, Ltd., National University Corporation Nara Institute of Science and Technology
InventorsTakeyoshi Masuda, Tomoaki Hatayama
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Abstract
On a substrate, a silicon carbide layer provided with a main surface is formed. A mask is formed to cover a portion of the main surface of the silicon carbide layer. The main surface of the silicon carbide layer on which the mask is formed is thermally etched using chlorine-based gas so as to provide the silicon carbide layer with a side surface inclined relative to the main surface. The step of thermally etching is performed in an atmosphere in which the chlorine-based gas has a partial pressure of 50% or smaller.
Claims10
A method for manufacturing a silicon carbide semiconductor device, comprising the steps of:
- forming a silicon carbide layer on a substrate, said silicon carbide layer being provided with a main surface;
- forming a mask covering a portion of said main surface of said silicon carbide layer;
- forming a recess by etching said silicon carbide layer by means of a reactive ion etching or an ion milling using said mask;
- and
- thermally etching a side surface of said recess using said mask and chlorine-based gas at a temperature of not less than 700 degrees Celsius and not more than 1200 degrees Celsius in an atmosphere with reduced pressure in which said chlorine-based gas has a partial pressure of 50% or less so as to incline said side surface of said recess relative to said main surface,
- wherein said atmosphere with reduced pressure has a pressure of not more than 1/10 of an atmospheric pressure.
A method for manufacturing a silicon carbide semiconductor device, comprising the steps of:
- forming a silicon carbide layer on a substrate , said silicon carbide layer being provided with a main surface;
- forming a mask covering a portion of said main surface of said silicon carbide layer;
- forming a recess by etching said silicon carbide layer by means of a reactive ion etching or an ion milling using said mask;
- and
- thermally etching a side surface of said recess using said mask and chlorine-based gas at a temperature of not less than 700 degrees Celsius and not more than 1200 degrees Celsius in an atmosphere with reduced pressure so as to form an inclined surface including a {0-33-8} plane at said side surface of said recess,
- wherein said atmosphere with reduced pressure has a pressure of not more than 1/10 of an atmospheric pressure, and
- wherein the step of thermally etching is performed in an atmosphere in which said chlorine-based gas has a partial pressure of 50% or smaller.
A method for manufacturing a silicon carbide semiconductor device, comprising the steps of:
- forming a silicon carbide layer on a substrate, said silicon carbide layer being provided with a main surface;
- forming a mask covering a portion of said main surface of said silicon carbide layer;
- thermally etching said main surface of said silicon carbide layer on which said mask is formed, using chlorine-based gas so as to provide said silicon carbide layer with a side surface inclined relative to said main surface, the step of thermally etching being performed at 1000° C. or greater;
- forming a gate insulating film on said side surface of said silicon carbide layer;
- and
- forming a gate electrode facing said side surface of said silicon carbide layer with said gate insulating film being interposed therebetween,
- wherein the step of thermally etching is performed in an atmosphere with reduced pressure,
- wherein said atmosphere with reduced pressure has a pressure of not more than 1/10 of an atmospheric pressure, and
- wherein the step of thermally etching is performed in an atmosphere in which said chlorine-based gas has a partial pressure of 50% or smaller.
Dependencies are inferred from the claim text.