Poly-Si Thin Film Transistors: Effect of Metal Thickness on Silicon Crystallization


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In this work metal induced crystallization (MIC) using nickel (Ni) was employed to obtain poly-Si by crystallization of amorphous films for application as active layer in TFTs. Ni layers with thicknesses of 0.5 nm, 1 nm and 2 nm were used to crystallize the silicon. The TFTs were produced with a bottom gate configuration using a multi-layer Al2O3/TiO2 insulator produced by atomic layer deposition (ALD) as gate dielectric. The best performances of the TFT produced were obtained when using very thin Ni layers for the crystallization. This is attributed to a lower metal contamination and to the enhancement of grain size, as a result of the lower nucleation density achieved, when using the thinnest Ni layer. Devices that exhibit effective mobility of 45.5 cm2V-1s-1 and an on/off ratio of 5.55×104 were produced using a 0.5 nm Ni layer to crystallize the active channel area.



Materials Science Forum (Volumes 514-516)

Edited by:

Paula Maria Vilarinho




L. Pereira et al., "Poly-Si Thin Film Transistors: Effect of Metal Thickness on Silicon Crystallization", Materials Science Forum, Vols. 514-516, pp. 28-32, 2006

Online since:

May 2006




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