Large-grain polycrystalline silicon film by sequential lateral solidification on a plastic substrate

Polysilicon thin-film transistors on polymer substrates

“…Laser irradiation was generally performed, in the case of relatively high sputtering gas content, by using a ramped beam profile to effuse out gradually the gas [15] or by using a multi-shot irradiation with increasing energy densities [14]. In the case of low sputtering gas content (o1 at%) the a-Si precursor films could stand to relatively high energy density direct irradiation inducing full melt of the film [37], thus allowing the possibility to adopt the sequential lateral solidification (SLS) irradiation scheme [37] and the achievement of elongated grains 6 mm long. However, several issues currently limit the implementation of sputtering technology including: (i) particle generation, which are at levels well above the tolerable densities [36]; (ii) relatively low deposition rates, especially for light sputtering gases as He, which are not compatible with mass production requirements; (iii) lack of mass production equipment.…”

Fabrication of self-aligned TFTs with a ultra-low temperature polycrystalline silicon process on metal foils

“…The Ar pressure appeared to be the most important factor in adjusting densities, while the RF power effect saturated rather fast. Details can be found elsewhere [10]. Fig.…”

P-2: High Performance of Polycrystalline Silicon TFT on Plastic Substrate Processed at Very Low Temperatures

“…In the small thickness region below 120 nm, the maximum laser energy densities is decreased from 550 mJ/cm 2 to 350 mJ/cm 2 which is due to the released heat from an absorption layer which damages the buffer oxide II layer. When the thickness is greater than 170 nm, the maximum laser energy density saturates above 750 mJ/cm 2 from the a-Si film characteristics [4]. On the top of the buffer layer we deposited an 80 nm thick a-Si film for active layer at RF power of 1 kW and Ar pressure of 0.48 Pa.…”

“…The aforementioned issues as well as the low thermal resistance of most plastic substrates necessitate an ultra low temperature poly-Si (ULTPS) TFTs process [2,3]. Large grain poly-Si film was successfully obtained by sequential lateral solidification (SLS) on a plastic substrate [4].…”