TY - JOUR
T1 - GaN cleaning by Ga deposition, reduction and re-evaporation
T2 - Proceedings of the 1999 3rd International Conference on Nitride Semiconductors (ICNS'99)
AU - Maffeis, T. G.G.
AU - Clark, S. A.
AU - Dunstan, P. R.
AU - Wilks, S. P.
AU - Evans, D. A.
AU - Peiro, F.
AU - Riechert, H.
AU - Parbrook, P. J.
N1 - Copyright:
Copyright 2004 Elsevier Science B.V., Amsterdam. All rights reserved.
PY - 1999/11
Y1 - 1999/11
N2 - The Ga deposition, reduction, and re-evaporation technique commonly used to produce clean n-GaN surfaces and Ag-GaN interface formation on the resultant surface, have been investigated by Soft X-ray Photoelectron Spectroscopy (SXPS) and current-voltage measurements. SXPS studies have indicated that Ga deposition produces a band-bending of ΔEk = +1.0 eV to higher kinetic energy. Our results show this shift to be a partially reversible process: re-evaporation of the deposited Ga resulted in a Fermi shift of ΔEk = -0.6 eV to lower energy. Ag deposition did not cause any further Fermi shift, indicating that the Fermi level is pinned (2.2±0.2) eV above the valence band edge, possibly as a consequence of the cleaning procedure itself. Current voltage (I-V) measurements have shown a barrier height of 0.77 eV and an ideality factor of 1.6. Metal induced gap states and the unified defect model are discussed as possible barrier formation mechanisms.
AB - The Ga deposition, reduction, and re-evaporation technique commonly used to produce clean n-GaN surfaces and Ag-GaN interface formation on the resultant surface, have been investigated by Soft X-ray Photoelectron Spectroscopy (SXPS) and current-voltage measurements. SXPS studies have indicated that Ga deposition produces a band-bending of ΔEk = +1.0 eV to higher kinetic energy. Our results show this shift to be a partially reversible process: re-evaporation of the deposited Ga resulted in a Fermi shift of ΔEk = -0.6 eV to lower energy. Ag deposition did not cause any further Fermi shift, indicating that the Fermi level is pinned (2.2±0.2) eV above the valence band edge, possibly as a consequence of the cleaning procedure itself. Current voltage (I-V) measurements have shown a barrier height of 0.77 eV and an ideality factor of 1.6. Metal induced gap states and the unified defect model are discussed as possible barrier formation mechanisms.
UR - http://www.scopus.com/inward/record.url?scp=0033221927&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1521-396X(199911)176:1<751::AID-PSSA751>3.0.CO;2-I
DO - 10.1002/(SICI)1521-396X(199911)176:1<751::AID-PSSA751>3.0.CO;2-I
M3 - Article
AN - SCOPUS:0033221927
SN - 0031-8965
VL - 176
SP - 751
EP - 754
JO - Physica Status Solidi (A) Applied Research
JF - Physica Status Solidi (A) Applied Research
IS - 1
Y2 - 4 July 1999 through 9 July 1999
ER -