INTEGRATED HETEROSTRUCTURE OF GROUP II-VI SEMICONDUCTOR MATERIALS INCLUDING EPITAXIAL OHMIC CONTACT AND METHOD OF FABRICATING SAME

摘要

An ohmic contact to a p-type zinc selenide (ZnSe) layer (17) in a Group II-VI semiconductor device, includes a zinc mercury selenide (ZnxHg1-xSe) or zinc telluride selenide (ZnTexSe1-x) layer (19) on the zinc selenide layer, a mercury selenide (HgSe) layer (18) on the zinc mercury selenide or zinc telluride selenide layer and a conductor (such as metal) layer on the mercury selenide layer. The zinc mercury selenide or zinc telluride selenide and mercury selenide layers between the p-type zinc selenide and the conductor layer (13) provide an ohmic contact by eliminating the band offset between the wide bandgap zinc selenide and the conductor. Step graded, linear graded, and parabolic graded layers of zinc mercury selenide or zinc telluride selenide may be provided. The ohmic contact of the present invention produces nearly ideal voltage-current relation, so that high efficiency Group II-VI optoelectronic devices may be obtained. The integrated heterostructure is formed by epitaxially depositing the ohmic contact on the Group II-VI device. A removable overcoat layer may be formed on the Group II-VI device to allow room temperature atmospheric pressure transfer of the device from a zinc based deposition chamber to a mercury based deposition chamber, for deposition of the ohmic contact. The integrated heterostructure may also be formed by forming an optical emission heterostructure including an epitaxial ohmic contact on a first substrate, bonding the ohmic contact to a second substrate, and then removing the first substrate.