The role of N-Si-O bonding configurations in tunable photoluminescence of oxygenated amorphous silicon nitride films

Journal Article · Mon Jun 08 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4922465· OSTI ID:22423748

Zhang, Pengzhan ^[1]; Chen, Kunji; Lin, Zewen; Li, Wei; Xu, Jun; Huang, Xinfan ^[1]; Dong, Hengping ^[2]

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1. State Key Laboratory of Solid State Microstructures and School of Electron Science and Engineering, Nanjing University, Nanjing 210093 (China)
2. Taizhou Institute of Science and Technology, Nanjing University of Science and Technology, Taizhou 225300 (China)

Last year, we have reported that the internal quantum efficiency of photoluminescence (PL) from amorphous silicon oxynitride (a-SiN{sub x}O{sub y}) films has been achieved as high as 60%. The present work intensively investigated the mechanisms for tunable PL in the 2.05–2.95 eV range from our a-SiN{sub x}:O films, by using a combination of optical characterizations, X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) measurements. The results of XPS, EPR, and photoluminescence excited measurements indicated that the incorporation of oxygen atoms into silicon nitride (a-SiN{sub x}) networks not only reduced the band tail structure disorder (Urbach tail width E{sub U}) but also created N-Si-O (N{sub x}) defect states in the band gap. We have discovered the distinctive PL characteristics from a-SiN{sub x}:O films with various NH{sub 3/}SiH{sub 4} ratios. The PL peak energy (E{sub PL}) is independent of the excitation energy (E{sub exc}) and the PL intensity (I{sub PL}) is regardless of the optical band gap (E{sub opt}) but is proportional to the N{sub x} defects concentration, both of which are completely different from the PL characteristics by band tail states recombination mechanism, in which the E{sub PL} is proportional to E{sub exc} (when E{sub exc} ≤ E{sub opt}) and the I{sub PL} is dependent on the relative position of E{sub exc} and E{sub opt}. Based on the N-Si-O bonding configurations and the distinctive PL characteristics, the radiative recombination mechanism through the N-Si-O defect states has been proposed, by which the performance of stimulated emission may be realized in this kind of a-SiN{sub x}:O films.

• OSTI ID: 22423748
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 23 Vol. 106; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMMONIA
BINDING ENERGY
CRYSTAL DEFECTS
ELECTRON SPIN RESONANCE
FILMS
OXYGEN
PHOTOLUMINESCENCE
QUANTUM EFFICIENCY
SILANES
SILICON
SILICON NITRIDES
STIMULATED EMISSION
X-RAY PHOTOELECTRON SPECTROSCOPY