Controlling defect and Si nanoparticle luminescence from silicon oxynitride films with CO{sub 2} laser annealing

Journal Article · Mon Feb 27 00:00:00 EST 2006 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.2178769· OSTI ID:20778758

Tewary, Anuranjita; Kekatpure, Rohan D; Brongersma, Mark L ^[1]

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1. Geballe Laboratory of Advanced Materials, Stanford University, 476 Lomita Mall, Stanford, California 94305 (United States)

We demonstrate that a focused CO{sub 2} laser beam ({lambda}=10.6 {mu}m) can be employed to locally synthesize light emitting defects and Si nanoparticles in silicon rich oxynitride thin films. Films with a stoichiometry of SiO{sub 1.08}N{sub 0.32} were prepared by plasma enhanced chemical vapor deposition with N{sub 2}O and SiH{sub 4}. Strongly absorbing CO{sub 2} laser light was then used to induce local heating in the films in air ambient using power densities in the range from 0 to 580 W/cm{sup 2} and times of 5 s to 60 min. High-resolution cross sectional transmission electron microscopy (TEM) images of the irradiated region revealed the presence of crystalline Si nanoparticles. Photoluminescence (PL) spectra taken from irradiated areas showed two distinct peaks around 570 and 800 nm. From a combined TEM, Rutherford back scattering (RBS), forming gas annealing (FGA), PL, and PL lifetime study it is concluded that the 570 nm peak with a short PL lifetime (<10 ns) is related to defects characteristic of silicon suboxides and that the 800 nm peak is due to exciton recombination inside the Si nanoparticles. The appearance of an isosbestic point in the PL spectra suggests that upon CO{sub 2} laser heating Si nanoparticles are formed at the expense of the luminescent defect structures, which are annealed out.

• OSTI ID: 20778758
• Journal Information: Applied Physics Letters, Vol. 88, Issue 9; Other Information: DOI: 10.1063/1.2178769; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION SPECTRA
ANNEALING
CARBON DIOXIDE LASERS
CHEMICAL VAPOR DEPOSITION
CRYSTAL DEFECTS
EXCITONS
NANOSTRUCTURES
NITROUS OXIDE
PARTICLES
PHOTOLUMINESCENCE
PLASMA
POWER DENSITY
RECOMBINATION
RUTHERFORD BACKSCATTERING SPECTROSCOPY
SEMICONDUCTOR MATERIALS
SILANES
SILICON
STOICHIOMETRY
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY