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0910-A12-03

Blue Light Emission from PECVD Deposited Nanostructured SiC Liudmyla Ivashchenko1, Andriy Vasin2, Volodymyr Ivashchenko3, Mykola Ushakov4, and Andriy Rusavsky5 1 Lab. ¹ 61, Institute for Problems of Material Science, NAS of Ukraine, 3 Krzhyzhanovsky str., 03142 Kyiv, Ukraine, Kyiv, 03142, Ukraine 2 Lab.¹15, Institute of Semiconductor Physics, NAS, Ukraine, Kyiv, 03026, Ukraine 3 Lab.¹61, Institute for Problems of Material Science, NAS Ukraine, Kyiv, 03142, Ukraine 4 Lab.¹61, Institute for Problems of Material Science, NAS, Ukraine, Kyiv, 03142, Ukraine 5 Istitute of Semiconductor Physics, NAS, Ukraine, Kyiv, 03026, Ukraine ABSTRACT Experimental data on the room temperature blue light emission from nanocrystalline silicon carbide (nc-SiC) films are presented. The silicon carbide films were deposited on silicon substrates with a plasma enhanced chemical vapor deposition (PECVD) reactor from methyltrichlorosilane at substrate temperature in the range of 200-350 0C. The film deposited at 350 0C is nanostructured and X-ray diffraction proves the presence of the 3C-SiC crystallites. Infrared absorption spectroscopy in the region of Si-C, C-H, C-O, Si-H and Si-O bonds show the corresponding absorption bands. X-ray photoelectron spectroscopy studies confirm this bond picture. Photoluminescence was measured at 77 and 300 K. The bright blue emission has a double-peak structure at 415 and 437 nm. To clarify the origin of such an emission, tight binding molecular dynamics (TB-MD) simulations of several SiC and Si nanoclusters were carried out. Based on the temperature dependence of the photoluminescence and on the simulation data, a possible model of radiative recombination in nc-SiC films was proposed. According to this model, the emission bands at 415 and 437 nm are assigned to band-to-band and band-to-tail recombination in the nanocrystallite core. The recombination at band tails of the interface and SiC-O-H amorphous tissue gives rise to a shoulder around 470 nm. INTRODUCTION The emission properties of silicon-based semiconductors have been widely studied in the last years, due to the discovery of visible photoluminescence (PL) from porous Si (PS) at room temperature [1]. Many investigations have focused on fabrication and blue-emitting properties of such semiconductors, because blue emission is of great importance for applications in modern optoelectronics. In this respect, among a great number of semiconductor materials, Si nanostructres turned out to be very promising. It was reported earlier that some nanostructured Si-based materials exhibit the bright blue PL with a double-peak structure at approximately 415420 and 430-440 nm. It is these materials that are the subject of the present investigation. The blue emission with the double-peak structure was observed in: anodized microdrystalline Si thin films [2]; Si+ -implanted SiO2 films [3]; strongly oxidized PS [4]; ECR-CVD nc-SiC films [5,6]; nc-Si/SiO2 multilayers [7]; PS embedded in Pb(ZrxTi1-x)O3 [8]; C+ -implanted silicon wafers with a sequent thermal d