Electronic and optical properties of ScN and (Sc,Mn)N thin films deposited by reactive DC-magnetron sputtering

Journal Article · Wed Aug 14 00:00:00 EDT 2013 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4817715· OSTI ID:22218235

Saha, Bivas ^[1]; Naik, Gururaj; Boltasseva, Alexandra ^[2]; Drachev, Vladimir P. ^[2]; Marinero, Ernesto E. ^[1]; Sands, Timothy D. ^[1]

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1. School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)
2. Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)

Scandium nitride (ScN) is a rocksalt semiconductor that has attracted significant attention from various researchers for a diverse range of applications. Motivated by the prospect of using its interesting electronic structure for optoelectronic and dilute magnetic semiconductor applications, we present detailed studies of the electronic transport and optical properties of ScN and its alloys with manganese nitride (MnN). Our results suggest (a) dilute manganese doping in ScN compensates for the high n-type carrier concentrations arising due to oxygen impurities and (b) an n-type to p-type carrier type transition occurs at a composition between 5.8% and 11% Mn on Sc sites. In terms of its optical properties, our analysis clearly indicates direct and indirect bandgap absorption edges of ScN located at 2.04 eV and 1.18 eV, respectively. In addition to the direct gap absorption edge, (Sc,Mn)N samples also show Mn-defect induced electronic absorption. Photoluminescence measurements at room temperature from ScN films exhibit a yellowish-green emission corresponding to direct gap radiative recombination. Direct gap recombination is not expected given the smaller indirect gap. A possible role of high excitation intensities in suppressing relaxation and recombination across the indirect bandgap is suspected. Raman spectroscopic and ellipsometric characterization of the dielectric permittivities of ScN and (Sc,Mn)N are also presented to assist in understanding the potential of ScN for optoelectronic applications.

• OSTI ID: 22218235
• Journal Information: Journal of Applied Physics, Vol. 114, Issue 6; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
CONCENTRATION RATIO
DIELECTRIC MATERIALS
EV RANGE
IMPURITIES
MAGNETIC SEMICONDUCTORS
MAGNETRONS
MANGANESE
MANGANESE NITRIDES
OPTICAL PROPERTIES
PERMITTIVITY
PHOTOLUMINESCENCE
RAMAN SPECTRA
RECOMBINATION
SCANDIUM
SCANDIUM NITRIDES
SPUTTERING
THIN FILMS