Low resistance ohmic contacts on wide band-gap GaN
- 21 February 1994
- journal article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 64 (8) , 1003-1005
- https://doi.org/10.1063/1.111961
Abstract
We report a new metallization process for achieving low resistance ohmic contacts to molecular beam epitaxy grown n‐GaN (∼1017 cm−3) using an Al/Ti bilayer metallization scheme. Four different thin‐film contact metallizations were compared during the investigation, including Au, Al, Ti/Au, and Ti/Al layers. The metals were first deposited via conventional electron‐beam evaporation onto the GaN substrate, and then thermally annealed in a temperature range from 500 to 900 °C in a N2 ambient using rapid thermal annealing techniques. The lowest value for the specific contact resistivity of 8×10−6 Ω cm2, was obtained using Ti/Al metallization with anneals of 900 °C for 30 s. X‐ray diffraction and Auger electron spectroscopy depth profile were employed to investigate the metallurgy of contact formation.Keywords
This publication has 9 references indexed in Scilit:
- High electron mobility transistor based on a GaN-AlxGa1−xN heterojunctionApplied Physics Letters, 1993
- A comparative study of GaN epilayers grown on sapphire and SiC substrates by plasma-assisted molecular-beam epitaxyApplied Physics Letters, 1993
- Recent developments in ohmic contacts for III–V compound semiconductorsJournal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, 1992
- High-Power GaN P-N Junction Blue-Light-Emitting DiodesJapanese Journal of Applied Physics, 1991
- Interfacial Reactions between In/Pd and GaAsMRS Proceedings, 1991
- P-Type Conduction in Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI)Japanese Journal of Applied Physics, 1989
- Electronic structures and doping of InN, N, and NPhysical Review B, 1989
- Ohmic contacts to n-GaAs using In/Pd metallizationApplied Physics Letters, 1987
- On the thermal decomposition of GaN in vacuumPhysica Status Solidi (a), 1974