Effect of rapid thermal annealing temperature on the dispersion of Si nanocrystals in SiO2 matrix Nupur Saxena, Pragati Kumar, and Vinay Gupta Citation: AIP Conference Proceedings 1661, 080026 (2015); doi: 10.1063/1.4915417 View online: http://dx.doi.org/10.1063/1.4915417 View Table of Contents: http://scitation.aip.org/content/aip/proceeding/aipcp/1661?ver=pdfcov Published by the AIP Publishing Articles you may be interested in A low thermal impact annealing process for SiO2-embedded Si nanocrystals with optimized interface quality J. Appl. Phys. 115, 134311 (2014); 10.1063/1.4870819 Interaction of Co with Si and SiO2 during rapid thermal annealing J. Appl. Phys. 69, 7612 (1991); 10.1063/1.347530 Effects of rapid thermal annealing and SiO2 encapsulation on GaInAs/AlInAs heterostructures Appl. Phys. Lett. 56, 1365 (1990); 10.1063/1.103204 Rapid thermal annealing of YBaCuO thin films deposited on SiO2 substrates J. Appl. Phys. 66, 1866 (1989); 10.1063/1.344363 Rapid thermal annealing of YBaCuO films on Si and SiO2 substrates Appl. Phys. Lett. 53, 153 (1988); 10.1063/1.100578
This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP: 14.139.45.244 On: Thu, 21 May 2015 09:28:32
Effect of Rapid Thermal Annealing Temperature on the Dispersion of Si Nanocrystals in SiO2 Matrix Nupur Saxenaa), Pragati Kumar, Vinay Gupta Department of Physics & Astrophysics, University of Delhi, Delhi-110007, India a)
Corresponding author:
[email protected]
Abstract. Effect of rapid thermal annealing temperature on the dispersion of silicon nanocrystals (Si-NC’s) embedded in SiO2 matrix grown by atom beam sputtering (ABS) method is reported. The dispersion of Si NCs in SiO 2 is an important issue to fabricate high efficiency devices based on Si-NC’s. The transmission electron microscopy studies reveal that the precipitation of excess silicon is almost uniform and the particles grow in almost uniform size upto 850 C. The size distribution of the particles broadens and becomes bimodal as the temperature is increased to 950 C. This suggests that by controlling the annealing temperature, the dispersion of Si-NC’s can be controlled. The results are supported by selected area diffraction (SAED) studies and micro photoluminescence (PL) spectroscopy. The discussion of effect of particle size distribution on PL spectrum is presented based on tight binding approximation (TBA) method using Gaussian and log-normal distribution of particles. The study suggests that the dispersion and consequently emission energy varies as a function of particle size distribution and that can be controlled by annealing parameters.
INTRODUCTION Nanodimensional silicon has been explored since more than two decades in different forms, viz. porous silicon 1, amorphous or nanocrystalline silicon embedded in various matrices 2, nanowires3, nanorods4 etc. due to its wide applications in photovoltaics5, sensors6 and CMOS compatible devices 7. Among these silicon nanocrystals (Si-NC’s) embedded in SiO2 matrix have emerged as the most promising candidate for future integrated optoelectronics. The optical properties of these nanocrystals depend on various factors like size, size distribution, crystalline quality, crystals structure, and defect states etc, which are the outcomes of synthesis process and post treatments. Si-NC’s embedded in SiO2 matrix have been synthesized by deposition of silicon rich silicon oxide (SiO X, X
