Title: Non-thermal alloyed ohmic contact process of GaN-based HEMTs by pulsed laser annealing
Authors: Tzou, An-Jye
Hsieh, Dan-Hua
Chen, Szu-Hung
Li, Zhen-Yu
Chang, Chun-Yen
Kuo, Hao-Chung
Department of Electrophysics
College of Electrical and Computer Engineering
Department of Photonics
Keywords: GaN;HEMTs;pulse laser annealing;ion implantation
Issue Date: May-2016
Abstract: We have demonstrated Si implantation incorporation into GaN HEMTs with a non-alloyed ohmic contact process. We optimized the power density of pulsed laser annealing to activate implanted Si dopants without a thermal metallization process. The experimental results show that the GaN surface will be reformed under the high power density of the illumination conditions. It provides a smooth surface for following contact engineering and leads to comparable contact resistance. The transmission line model (TLM) measurement shows a lower contact resistance to 6.8. x. 10(-7) Omega . cm(2) via non-alloyed contact technology with significantly improved surface morphology of the contact metals. DC measurement of HEMTs shows better current and on-resistance. The on-resistance could be decreased from 2.18 to 1.74 m Omega-cm(2) as we produce a lower contact resistance. Pulsed laser annealing also results in lower gate leakage and smaller dispersion under a pulse I-V measurement, which implies that the density of the surface state is improved.
URI: http://dx.doi.org/10.1088/0268-1242/31/5/055003
ISSN: 0268-1242
DOI: 10.1088/0268-1242/31/5/055003
Volume: 31
Issue: 5
Appears in Collections:Articles