Cubic silicon carbide film manufacturing method, and cubic silicon carbide film-attached substrate manufacturing method

Abstract

A method for manufacturing a cubic silicon carbide film includes: a first step of introducing a carbon-containing gas onto a silicon substrate and rapidly heating the silicon substrate to an epitaxial growth temperature of cubic silicon carbide so as to carbonize a surface of the silicon substrate and form a cubic silicon carbide film; and a second step of introducing a carbon-containing gas and a silicon-containing gas onto the cubic silicon carbide film while maintaining the cubic silicon carbide film at the epitaxial growth temperature of cubic silicon carbide, so as to allow further epitaxial growth of the cubic silicon carbide film.

Description

[0001]The entire disclosure of Japanese Patent Application No. 2010-181206, filed Aug. 13, 2010 is expressly incorporated by reference herein.BACKGROUND[0002]1. Technical Field[0003]The present invention relates to cubic silicon carbide film manufacturing methods, and cubic silicon carbide film-attached substrate manufacturing methods. Specifically, the invention relates to a cubic silicon carbide film manufacturing method that forms a cubic silicon carbide (SiC) film, an expected wide bandgap semiconductor, on a silicon substrate or on a monocrystalline silicon film formed on the substrate, and to a method for manufacturing a cubic silicon carbide film-attached substrate that includes a cubic silicon carbide film formed on a silicon substrate or on a monocrystalline silicon film formed on the substrate.[0004]2. Related Art[0005]Silicon carbide (SiC), a wide bandgap semiconductor having a bandgap of 2.2 eV (300 K) more than twice as large as that of silicon (Si), has generated inter...

AI Technical Summary

Benefits of technology

[0013]An advantage of some aspects of the invention is to provide a cubic silicon carbide film manufacturing method with which a high-quality cubic silicon carbide film with few crystal defects can be grown at high speed, and a cubic silicon carbide film-attached substrate manufacturing method with which a high-quality cubic silicon carbide film with few crystal defects can be grown at high speed on a silicon substrate, or on a monocrystalline silicon film formed on the substrate.

Problems solved by technology

The crystal forming temperature of silicon carbide (SiC) is higher than that of silicon (Si), and obtaining silicon carbide (SiC) single crystal ingots by a pull method from a liquid phase is not as easy as in silicon.

However, it is difficult with the sublimation method to obtain large-diameter silicon carbide (SiC) single crystal ingots that have few crystal defects.

This has limited the diameter of the currently available silicon carbide (SiC) substrates in the market to 3 to 4 inches, and has made the price of these products very expensive.

This, combined with different coefficients of thermal expansion, makes it very difficult to obtain a high-quality epitaxial film that has few crystal defects.

The stress translates into crystal defects in the cubic silicon carbide film.

A drawback of lowering growth temperature is that it slows the growth rate.

Thus, the different coefficients of thermal expansion cause stress while cooling the substrate, and the stress translates into crystal defects.

It has thus been difficult to reduce the crystal defects of the cubic silicon carbide film.

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