Nano electron field emitters synthesized using excimer laser assisted metal induced crystallization of thin silicon films

Hydrogenated amorphous thin silicon films (a-Si:H) deposited using Plasma Enhanced Chemical Vapor Deposition (PECVD) on metal coated glass substrates were investigated to analyze the effect of a novel processing technique known as Laser Assisted Metal Induced Crystallization (LAMIC) on their Electron Field Emission (FE) properties. Post-surface characterization of the processed LAMIC thin silicon films showed increased surface roughness and the presence of uniformly spaced “island-like” micro-nano structures on the surface of metal coated backplane samples. Best diode configuration FE results were obtained from samples sputtered with a thin layer of aluminum (Al) on top and cross laser annealed at 190 mJ/cm² (y-axis) and 100 mJ/cm² (x-axis). FE currents were measured as high as 12 µA at emission thresholds of 8-30 V/µm. FE results of the LAMIC thin silicon films were found to be particularly dependent on laser fluence and the surface morphology exhibited very high discharge resistance. Oxidation of LAMIC films was observed to deteriorate the FE characteristics, thereby increasing the emission threshold to 30-35 V/µm. Finally, a hybrid emission model has been proposed that explains the electron emission from such LAMIC thin silicon films.