CW laser induced crystallization of thin amorphous silicon films deposited by EBE and PECVD
This work presents the Continuous Wave (CW) laser crystallization of thin amorphous silicon (a-Si) films deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) and by Electron Beam Evaporation (EBE) on low cost glass substrate. The films are characterized by Elastic Recoil Detection Analysis (ERDA) and by Fourier-Transform Infrared (FTIR) spectroscopy to evaluate the hydrogen content. Analysis shows that the PECVD films contain a high hydrogen concentration (∼10 at.%) while the EBE films are almost hydrogen-free. It is found that the hydrogen is in a bonding configuration with the a-Si network and in a free form, requiring a long thermal annealing for exodiffusion before the laser treatment to avoid explosive effusion. The CW laser crystallization process of the amorphous silicon films was operated in liquid phase regime. We show by Electron Backscatter Diffraction (EBSD) that polysilicon films with large grains can be obtained with EBE as well as for the PECVD amorphous silicon provided that for the latest the hydrogen content is lower than 2 at.%. © 2012 Elsevier B.V.
Keywords: Amorphous silicon ; Amorphous silicon (a-Si) ; Amorphous silicon film ; Bonding configurations ; Continuous wave lasers ; Continuous waves ; crystallization ; CW laser ; CW laser crystallization ; Elastic recoil detection analysis ; Electron back scatter diffraction ; Electron beam evaporation ; Electron beams ; Exodiffusion ; Explosive bonding ; Fourier transform infrared spectroscopy ; Freeforms ; FTIR ; Glass substrates ; Hydrogen ; Hydrogenated amorphous silicon ; Hydrogen concentration ; Hydrogen contents ; Large-grain ; Laser crystallization ; Laser-induced crystallization ; Laser treatment ; Liquid Phase ; Low costs ; Metallic films ; Plasma enhanced chemical vapor deposition ; Polycrystalline silicon ; Polysilicon ; Polysilicon films ; Substrates ; Thermal-annealing ; Thin film ; Thin films
Record created on 2014-11-14, modified on 2016-08-09