Title :
Multi layer metallization scheme (Ni/Pd/Ag) ohmic contact on p-type GaN
Author :
Lim, C.W. ; Tan, C.K. ; Abdul Aziz, A. ; Hassan, Z. ; Yam, F.K.
Author_Institution :
Sch. of Phys., Univ. Sains Malaysia, Penang, Malaysia
Abstract :
In this work, we report on the characteristics of the first ever work using a multilayer Ni/Pd/Ag contacts on p-GaN with the carrier concentration of 8 1017 cm-3. The electrical behavior and thermal stability at different annealing temperatures (400 C-800 C) with annealing time of 5 minutes and 10 minutes were investigated. Specific contact resistivity using transmission line method (TLM) and current voltage (I-V) measurements were investigated. The minimum specific contact resistivity of 2.8 10-1 Ω-cm2 was achieved after annealing at 400 C for 5 minutes. As-deposited samples exhibited near linear characteristics. Changes in the surface morphology of the contacts were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The agglomeration of the samples increased with the annealing temperatures.
Keywords :
III-V semiconductors; annealing; atomic force microscopy; gallium compounds; metallisation; nickel alloys; ohmic contacts; palladium alloys; scanning electron microscopy; silver alloys; surface morphology; thermal stability; wide band gap semiconductors; 10 mins; 400 to 800 C; 5 mins; GaN; Ni-Pd-Ag; annealing temperatures; atomic force microscopy; carrier concentration; contact resistivity; current voltage measurements; electrical behavior; multilayer metallization scheme; ohmic contact; p-type GaN; scanning electron microscopy; surface morphology; thermal stability; transmission line method; Annealing; Atomic force microscopy; Conductivity; Gallium nitride; Metallization; Nonhomogeneous media; Ohmic contacts; Scanning electron microscopy; Temperature; Thermal stability;
Conference_Titel :
Semiconductor Electronics, 2004. ICSE 2004. IEEE International Conference on
Print_ISBN :
0-7803-8658-2
DOI :
10.1109/SMELEC.2004.1620877