Vapor-phase method for growing mercury cadmium telluride

• Main Author: JACKSON, JR.; DAVID A
• Format: Patent
• Language: English
• Published: 27.03.1984
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; CHEMISTRY; CRYSTAL GROWTH; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

The growth of mercury cadmium telluride (Hg(1-x)Cdx Te) alloys is carried out by the pyrolytic decomposition of a mixture of Cd and Te alkyls in an atmosphere of Hg vapor; the ternary alloy is deposited as an epitaxial film on a CdTe single crystal substrate. The substrate is carried on a heated susceptor in a reactor vessel. The susceptor also has a cavity in which mercury is heated (at a temperature different from the substrate temperature) to provide Hg vapor. A mixture of dimethyl cadmium and diethyl tellurium gases flows through the reactor, the gases thermally decompose in the vicinity of the substrate, and combine with the Hg vapor to form Hg(1-x)CdxTe on the substrate. The relative proportions of dimethyl cadmium and diethyl tellurium determine x in the compound.