TY - JOUR
T1 - Thermally stable Ti/Al-based ohmic contacts to N-polar n-GaN by using an indium interlayer
AU - Kim, Sung Ki
AU - Han, Jae Chun
AU - Seong, Tae Yeon
N1 - Publisher Copyright:
© 2016 The Japan Society of Applied Physics.
PY - 2016/3
Y1 - 2016/3
N2 - The electrical properties of In/Ti/Al/Au contacts to N-polar n-GaN (nd = 5×1018cm%3) for high-power vertical light-emitting diodes were investigated at various thicknesses of the In layer, and compared with those of Ti/Al/Au contacts. Before annealing, both the Ti/Al/Au and In/Ti/Al/Au contacts were ohmic. After annealing at 300 C for 1 min, all of the samples exhibited some degradation of their electrical properties, although the In/Ti/Al/Au samples were more thermally stable. After annealing at 300 C for 60 min, the Ti/Al/Au contacts became non-ohmic, while the In (5 nm)/Ti/Al/Au contacts remained ohmic with a contact resistivity of 2.6×10%4?cm2. X-ray photoemission spectroscopy (XPS) results showed that, for all of the samples, annealing caused an increase in the content of interfacial oxygen. Based on the XPS and electrical results, the annealing dependence of the electrical characteristics of In/Ti/Al/Au contacts are described and discussed.
AB - The electrical properties of In/Ti/Al/Au contacts to N-polar n-GaN (nd = 5×1018cm%3) for high-power vertical light-emitting diodes were investigated at various thicknesses of the In layer, and compared with those of Ti/Al/Au contacts. Before annealing, both the Ti/Al/Au and In/Ti/Al/Au contacts were ohmic. After annealing at 300 C for 1 min, all of the samples exhibited some degradation of their electrical properties, although the In/Ti/Al/Au samples were more thermally stable. After annealing at 300 C for 60 min, the Ti/Al/Au contacts became non-ohmic, while the In (5 nm)/Ti/Al/Au contacts remained ohmic with a contact resistivity of 2.6×10%4?cm2. X-ray photoemission spectroscopy (XPS) results showed that, for all of the samples, annealing caused an increase in the content of interfacial oxygen. Based on the XPS and electrical results, the annealing dependence of the electrical characteristics of In/Ti/Al/Au contacts are described and discussed.
UR - http://www.scopus.com/inward/record.url?scp=84962026640&partnerID=8YFLogxK
U2 - 10.7567/JJAP.55.031001
DO - 10.7567/JJAP.55.031001
M3 - Article
AN - SCOPUS:84962026640
VL - 55
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 3
M1 - 031001
ER -