Varying nitrogen background pressure; an efficient approach to improve electrical properties of MBE-grown GaAs1-xNx thin films with less atomic disorder

被引:8
作者
Biswas, Mahitosh [1 ]
Shinde, Nilesh [2 ]
Makkar, Roshan Lal [3 ]
Bhatnagar, Anuj [3 ]
Chakrabarti, Subhananda [2 ]
机构
[1] Indian Inst Technol, Ctr Res Nanotechnol & Sci, Mumbai 400076, Maharashtra, India
[2] Indian Inst Technol, Dept Elect Engn, Mumbai 400067, Maharashtra, India
[3] Indian Inst Technol, Photon Div, Soc Appl Microwave Elect Engn & Res, Mumbai 400076, Maharashtra, India
关键词
SS-MBE; GaAs1-xNx; Electron mobility; Raman spectroscopy; Atomic disorder; Annealing; MOLECULAR-BEAM EPITAXY; MACROSCOPIC DEFECTS; QUANTUM-WELLS; BAND-GAP; GAASN; ORIGIN; GAINNAS; MECHANISMS; DEPENDENCE; SPECTRA;
D O I
10.1016/j.jallcom.2016.11.328
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Epitaxial GaAs1-xNx thin films were grown on GaAs (001) substrates through solid-source molecular beam epitaxy using an RF plasma source for incorporating nitrogen. We examined the thin films grown under different nitrogen background pressures (NBPs) using various ex-situ techniques. GaAs0.969N0.031 thin films grown under a high NBP of 5.5 x 10(-6) Torr exhibited thickness variation-induced Pendellosung fringes, a smooth surface with few Ga droplets, and a high electron mobility of 4020 cm(2)/(Vs), all of which evidence the high crystal quality. This is attributed to the reduction in surface recombination centers at elevated nitrogen concentrations. A high intensity of the GaAs LO1 and low intensity of the GaN-like local vibrational mode of the relaxed films were observed, attributed to less atomic disorder in the alloys. GaAs0.969N0.031 thin films exhibited near-band emission at 1.14 eV, close to the ideal band gap of (In) GaAsN (similar to 1 eV). Moreover, the photoluminescence intensity of films annealed at 750 degrees C exhibited a similar to 200-fold improvement over films annealed at 650 degrees C. Hence, superior-quality epitaxial GaAs0.0969N0.031 thin films grown through SS-MBE are an ideal substitute for (In) GaAsN in high-efficiency multijunction solar cell applications. (C) 2016 Elsevier B.V. All rights reserved.
引用
收藏
页码:3163 / 3169
页数:7
相关论文
共 39 条
[11]   Dominant mechanisms of electron scattering in ultra-dilute GaAsN [J].
Inagaki, Makoto ;
Ikeda, Kazuma ;
Kowaki, Hiroyuki ;
Ohshita, Yoshio ;
Kojima, Nobuaki ;
Yamagichi, Masafumi .
PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 10, NO 4, 2013, 10 (04) :589-592
[12]   ORIGIN OF SURFACE-DEFECTS ON MOLECULAR-BEAM EPITAXIALLY GROWN GAAS [J].
ITO, T ;
SHINOHARA, M ;
IMAMURA, Y .
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS, 1984, 23 (08) :L524-L526
[13]   Influence of N interstitials on the electronic properties of GaAsN alloys [J].
Jin, Y. ;
Jock, R. M. ;
Cheng, H. ;
He, Y. ;
Mintarov, A. M. ;
Wang, Y. ;
Kurdak, C. ;
Merz, J. L. ;
Goldman, R. S. .
APPLIED PHYSICS LETTERS, 2009, 95 (06)
[14]  
Jin Y., 2010, THESIS, P22
[15]   Origin of improved luminescence efficiency after annealing of Ga(In)NAs materials grown by molecular-beam epitaxy [J].
Li, W ;
Pessa, M ;
Ahlgren, T ;
Decker, J .
APPLIED PHYSICS LETTERS, 2001, 79 (08) :1094-1096
[16]   Lattice parameter in GaNAs epilayers on GaAs: Deviation from Vegard's law [J].
Li, W ;
Pessa, M ;
Likonen, J .
APPLIED PHYSICS LETTERS, 2001, 78 (19) :2864-2866
[17]   Composition and temperature dependence of the direct band gap of GaAs1-xNx(0≤x≤0.0232) using contactless electroreflectance [J].
Malikova, L ;
Pollak, FH ;
Bhat, R .
JOURNAL OF ELECTRONIC MATERIALS, 1998, 27 (05) :484-487
[18]  
Milanova M., 2011, SOLAR CELLS NEW ASPE, P82
[19]   Ordering effects in Raman spectra of coherently strained GaAs1-xNx [J].
Mintairov, AM ;
Blagnov, PA ;
Melehin, VG ;
Faleev, NN ;
Merz, JL ;
Qiu, Y ;
Nikishin, SA ;
Temkin, H .
PHYSICAL REVIEW B, 1997, 56 (24) :15836-15841
[20]   MOVPE growth and optical characterization of GaAsN films with higher nitrogen concentrations [J].
Nakajima, F. ;
Sanorpim, S. ;
Ono, W. ;
Katayama, R. ;
Onabe, K. .
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE, 2006, 203 (07) :1641-1644