Surface treatment effect on the poly-Si TFTs fabricated by electric field enhanced crystallization of Ni/a-Si:H films

Author

Kim, Binn ; Kim, Hae-Yeol ; Seo, Hyun-Sik ; Kim, Sung Ki ; Kim, Chang-Dong

Author_Institution

LCD Res. & Dev. Center, LG Philips, Kyunggi-Do, South Korea

Volume

24

Issue

12

fYear

2003

Firstpage

733

Lastpage

735

Abstract

Self-aligned, p-channel polycrystalline silicon thin-film transistors (TFTs) were fabricated by electric field enhanced crystallization of a-Si:H in contact with the Ni catalyst, where a chemical solution of 97.5% H/sub 2/O:1% HF:1.5% H/sub 2/O/sub 2/ was used for a surface treatment on polycrystalline silicon films. The wet surface treatment was found to remarkably improve the electrical properties of TFTs, especially the leakage current and subthreshold slope. The enhanced performance was confirmed to be from the removal of the Ni impurity remaining as defect states at the surface and also from the ameliorated surface roughness of the polycrystalline silicon films.

Keywords

X-ray fluorescence analysis; atomic force microscopy; crystallisation; crystallites; defect states; elemental semiconductors; leakage currents; semiconductor thin films; silicon; surface cleaning; surface roughness; thin film transistors; AFM; Ni impurity removal; Si; ameliorated surface roughness; electric field enhanced crystallization; energy dispersive X-ray fluorescence; leakage current; needle-like crystallites; polycrystalline silicon films; polysilicon TFT; self-aligned p-channel TFT; subthreshold slope; surface defect states; surface treatment effect; wet surface treatment; Chemicals; Crystallization; Impurities; Leakage current; Rough surfaces; Semiconductor films; Silicon; Surface roughness; Surface treatment; Thin film transistors;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2003.820626

Filename

1254601