1. Cathodoluminescence Properties of Silicon Thin Films Crystallized by Electron Beam Exposure P47 Advanced Display Research Center, Kyung Hee University 26 th International Vacuum Nanoelectronics Conference Thursday, July 11, 2013, Roanoke VA, USA Seon Yong Park 1, Su Woong Lee 1, Jung Soo Kang 1, Ha Rim Lee 1, Mi Yeon Joo 2, Jin Kyo Kim 2, and Kyu Chang Park 1 * 1 Department of Information Display, Advanced Display Research Center, Kyung Hee University, Dongdaemoon-ku, Seoul, 130-701, Korea 2 Department of Physics, Kyung Hee University *Corresponding author: kyupark@khu.ac.kr SEM images of the silicon thin films INTRODUCTION 1. Purpose of this study  Observing cathodoluminescence (CL) phenomenon from the electron beam exposed silicon thin film.  Analyzing the CL spectrum of the electron beam exposed silicon thin film with various exposure conditions.  Understanding origins of the CL and its relationship with structural properties of the electron beam exposed silicon thin film. 2. The cathodoluminescence  An optical and electromagnetic phenomenon in which electrons impacting on a luminescent material cause the emission of photons.  Luminescence comes from defect states in a material. EXPERIMENT EXPERIMENT Crystallization RESULTS RESULTS specimen SEM Mirror CL detector Defects EVEV ECEC hνhν e-e- Images of silicon thin films with different exposure conditions Bare silicon film (A)(B) CONCLUSION  We observed CL from the electron beam exposed silicon thin films.  CL property of silicon thin film is related to the structure of silicon.  The CL spectrum appeared only electron beam exposed area results from structural modifications.  The crystallized silicon thin films have grain sizes which are 10 ~ 50 nm.  The CL spectrum of visual range originates in the grains of the crystallized silicon thin films. RF Ar gas inlet DC e-e- e-e- e-e- e-e- e-e- e-e- e-e- e-e- e-e- Electron Gun Mesh Electron beam Sample Plate Glass a-Si:H Glass a-Si:H nc-Si E-beam exposure Peak (cm -1 )FWHM (cm -1 )Crystallinity (%) Exposed522.414.686.1 (A) Amorphous silicon(B) Electron beam exposed silicon Grain size distribution of the electron beam exposed silicon thin film 10 ~ 50 nm CL spectrum was observed at the electron beam exposed silicon thin film ! CL spectrum was observed at the electron beam exposed silicon thin film ! Raman result shows that the silicon thin film was crystallized very well by electron beam exposure ! (a) (b) E-beam exposure conditions Specification of samples ab RF forward300 W SubstrateGlass DC volt1.6 kV1.4 kV Deposition Method PE-CVD DC ampere160 mA190 mA Si thickness 300 nm Exposure time2 min Size50 x 50 mm 2 Ar gas3 sccm 5 sccm (a) E-beam exposed silicon films  Amorphous silicon thin film  no luminescence  Electron beam exposed silicon thin film  an intense visual luminescence Deconvolution results of two CL spectra (a) (b) 4 peaks fitting 5 peaks fitting The picture of actual CL emission during electron beam exposure Peak (nm)FWHM (nm) 47578 51842 590106 735112 Peak (nm)FWHM (nm) 47242 51637 556173 60247 733113 Actual CL emission of the electron beam exposed silicon thin film is a light like yellowish white. Electron beam exposure CL spectrum of the electron beam exposed silicon thin film Raman spectrum of silicon thin films 3 peaks fittingOriginal peak  The bands at 735 and 733 nm originate from a non-bridging oxygen hole center at Si-SiO 2 interface. Report from Appl. Phys. Lett. 99, 151902 (2011)  Other peaks appear to structural modifications.  detail study on the structural origin are needed. We split CL spectrum into several Gaussian functions and got a clue to the origin of CL !  Simple mechanism of CL and measurement system  Electron beam exposure system