Formation of ohmic contacts to MOCVD grown p-GaN by controlled activation of Mg.

Kaminska, E. ; Piotrowska, A. ; Barcz, A. ; Bour, D. ; Zielinski, M. ; Jasinski, J.

Technical Information Center Oak Ridge Tennessee

关键词: Hydrogen;    Magnesium;    Fabrication;    Heat treatments;    Morphology;   

RP-ID  :  DE2001772145

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

We report on the formation of low resistivity ohmic contacts to p-GaN, r(sub c) 10(sup (minus)4)(Omega)cm(sup 2), by increasing the concentration of the active Mg in the subcontact zone, via Zr-mediated release of hydrogen. We have investigated the process of evolution of hydrogen from MOCVD grown p-GaN via Zr-based metallization, and determined the optimum processing conditions (temperature and gas ambient) for fabrication of low resistance ohmic contacts. When the process is conducted in N(sub 2) flow, the metallization remains stable at temperatures required to achieve the ohmic behavior, and the morphology of the metal/semiconductor interface is unaltered by such a heat treatment. The processing in O(sub 2), on the contrary, causes the interdiffusion of metallization constituents and the incorporation of oxygen into the semiconductor subcontact region, which could be responsible for increased resistivity of these contacts.