FORMATION OF THREE−DIMENSIONAL STRUCTURES IN SILICON CARBIDE SUBSTRATES BY PLASMOCHEMISTRY ETCHING

This article is a review of the technology for the formation of three−dimensional structures in silicon carbide substrates. The technological solution of these problems ion−stimulation plasmochemistry etching in its various modifications, the most successful being by ICP sources (sources of inductively coupled plasma).

Silicon carbide consists of silicon and carbon which produce volatile fluorides in reaction with fluorine. Therefore for plasmochemistry etching of silicon carbide one uses fluorine−containing gases, most often sulfur hexafluoride (SF6), and sometimes with additions of oxygen and argon. During plasmochemistry etching of silicon carbide one  uses the  mask  the  material  of which does not interact with fluorine.  As a rule these are thin films of metals, e.g.  Cu, Al and Ni, and sometimes films of silicon oxides.

The most  important technological trend of this process is making through holes  by etching of SiC substrates with GaN epitaxial layers, and their subsequent metallization.

In this review we will present examples of ICP source applications for the formation of micro− and nano−sized three−dimensional structures in silicon carbide substrates, including  making  through holes  in SiC substrates with GaN epitaxial layers.

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