<p num="47">FIELD: technological processes.</p> <p num="48">SUBSTANCE: invention relates to the technology for producing semiconductor materials, in particular to the production of single-crystal wide-gap gallium nitride (GaN) plates with a hexagonal crystalline lattice. Method of producing the gallium nitride single crystal plate is characterized by the gradual formation of a layered structure: at the first stage, the SiC layer is formed on the Si (111) substrate by the method of atom substitution with the formation of carbon vacansion structures, at the second stage, the GaN N-polarity layer is formed on the obtained SiC layer by molecular beam epitaxy with plasma activation of nitrogen; at the third stage, the AlN Al-polarity layer is formed on the N-polarity GaN layer by the method of chloride hydride epitaxy, at the fourth stage, the GaN Ga-polarity layer is formed on the AlN Al-polarity layer by the method of chloride-hydride epitaxy, after which the resulting layered structure is kept in an alkaline