Ultra Large-Grain Poly-Si Thin-Film Transistor Using NiSi2 Seeding Si-Amplified Layer

• Published in: IEEE electron device letters Vol. 36; no. 8; pp. 778 - 780
• Main Authors: Jae Hyo Park, Hyung Yoon Kim, Chang Woo Byun, Seung Ki Joo
• Format: Journal Article
• Language: English
• Published: IEEE 01.08.2015
• Subjects: Crystallization; Grain boundaries; Grain size; Logic gates; NiSi2 seeds; poly-Si thin-film; Silicon; Silicon carbide; Thin film transistors; thin-film transistor (TFT); ultra-large-grains (ULG); Ultra-large-grains (ULG); poly-Si thin-film; thin-film transistor (TFT); NiSi2 seeds
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2015.2438874

A novel technique for enlarging grains of poly-Si thin-film has been successfully demonstrated, using a 1-μm thick Si-amplified layer (SAL) and NiSi 2 seeds on the top. It was applied to top-gated thin-film transistors (TFTs) and showed high electrical performance. The NiSi 2 seeds induce vertical crystallization in the SAL and migrate toward the bottom, forming columnar grains. The grain size of the poly-Si thin-film increases when the NiSi 2 seeds diffuse deeply into the SAL and eventually an ultralarge-grain (ULG) poly-Si thin film is formed. The SAL was removed for use in the fabrication of a top-gated TFT. The performance of the ULG poly-Si TFT was compared with that of a NiSi 2 seed-induced crystallized poly-Si TFT which was fabricated without an SAL.