Low-Temperature Polycrystalline Silicon Thin-Film Transistors Enhanced by Diode-Pumped Solid State Green Continuous-Wave Laser

Abstract:

A novel diode-pumped solid-state continuous-wave (CW) laser technology has been demonstrated for high-performance low-temperature polycrystalline silicon thin-film transistors (TFTs) fabrication. The CW laser-crystallized (CWC) poly-Si thin films indicated the excellent crystallinity with the flat surface morphology at grain boundary. Besides, the CW laser activation is a low-thermal budget process and can achieve the lower sheet resistance of 50 Ω/□ and uniformly redistributed dopant profiles. The n-channel CWC TFTs revealed the superior field-effect mobility reaching 505 cm²/V-s and the lower subthreshold swing as compared with the conventional excimer laser-crystallized ones.

• Periodical: Applied Mechanics and Materials (Volumes 217-219)
• Pages: 2230-2233
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.217-219.2230
• Online since: November 2012
• Authors: Jyh Liang Wang, Chun Chien Tsai, Chuan Chou Hwang, Tsang Yen Hsieh
• Keywords: Continuous-Wave Laser, Crystallization, Dopant Activation, Low-Temperature Polycrystalline Silicon (LTPS), Thin-Film Transistors (TFTs)

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