MgO-Based Coating for Electrically Insulating Semiconductive Substrates and Production Method Thereof

摘要

The present invention relates to a magnesium oxide-based (MgO) inorganic coating intended to electrically insulate semiconductive substrates such as silicon carbide (SiC), and to a method for producing such an insulating coating. The method of the invention comprises the steps of preparing a treatment solution of at least one hydrolysable organomagnesium compound and/or of at least one hydrolysable magnesium salt, capable of forming a homogeneous polymer layer of magnesium oxyhydroxide by hydrolysis/condensation reaction with water; depositing the treatment solution of the hydrolysable organomagnesium compound or of the hydrolysable magnesium salt, onto a surface to form a magnesium oxide-based layer; and densifying the layer formed at a temperature of less than or equal to 1000° C.

主权项

1. Method for producing a magnesium oxide-based electronically insulating inorganic layer, said method comprising the following steps:
(a) preparing a treatment solution of at least one hydrolysable organomagnesium compound, capable of forming a homogeneous polymer layer of magnesium oxyhydroxide by hydrolysis/condensation reaction with water; (b) depositing the treatment solution of the hydrolysable organomagnesium compound onto a surface in order to form a magnesium oxide-based layer; and (c) densifying the layer formed at a temperature of less than or equal to 1000° C. in order to obtain the magnesium oxide-based insulating layer, wherein the solvent of the treatment solution is an organic solvent selected from the group consisting of a saturated or unsaturated aliphatic alcohol of formula R5—OH, in which R5 represents an alkyl group having from 1 to 30 carbon atoms, or a phenyl group; and a diol of formula HO—R6—OH, in which R6 represents an alkyl group having from 1 to 30 carbon atoms, or a phenyl group; and wherein said treatment solution optionally further comprises
(i) one or more magnesium salts of formula (II):
MgA2  (II) in which A is a halide ion; and/or
(ii) one or more metal or metalloid salts or organometallic compounds of general chemical formula (III):
EtMu  (III) in which:
M is a metal or a metalloid;E is a group chosen from:
a hydrolysable group;a complexing agent;a β-diketone or a derivative of β-diketone;a phosphonate;a hydroxamate of formula R16—CO(NHOH), in which R16 is a linear or branched alkyl group having from 1 to 30 carbon atoms or a phenyl group;an organosilane;a sulphonate;a borate; ora diol of formula HO—R16—OH, in which R16 is a linear or branched alkyl group having from 1 to 30 carbon atoms, or a phenyl group, wherein t and u, respectively, represent the stoichiometry of E and M such that the compound (III) is an electrically neutral compound.