Quantitative Analysis of Deuterium Annealing Effect on Poly-Si TFTs by Low Frequency Noise and DC – Characterization

• Published in: IEEE transactions on electron devices 2018-04, Vol.65 (4), p.1640-1644
• Main Authors: Kim, Do-Hyun, Lim, Sung Kwan, Bae, Hagyoul, Kim, Choong-Ki, Lee, Seung-Wook, Seo, Myungsoo, Kim, Seong-Yeon, Hwang, Kyu-Man, Lee, Geon-Beom, Lee, Byoung Hun, Choi, Yang-Kyu
• Format: Article
• Language: English
• Subjects: Annealing; Dangling bond; Density; Deuterium; deuterium (D₂); Electron mobility; field-effect mobility (μ); hydrogen passivation; interface trap density (<italic xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">D it); LF noise; Logic gates; low frequency noise (<italic xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">LFN ); oxide trap density (<italic xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">N ot); Passivation; poly-crystalline silicon thin-film transistor (poly-Si TFT); Quantitative analysis; Semiconductor devices; Silicon; Silicon films; Thin film transistors; Transconductance
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2018.2805316

Deuterium (D 2 ) annealing was applied to a poly-crystalline silicon thin-film transistor (poly-Si TFT) to improve reliability and performance. The field-effect electron mobility ( \mu ) was extracted using the gate transconductance ( {g}_{m} ) method. It was found that \mu was improved before and after D 2 annealing. The interface trap density ( {D}_{\text {it}} ) as well as the oxide trap density ( {N}_{\text {ot}} ) in the poly-Si TFTs was quantitatively extracted using both conventional dc I-V characterization and analysis of low frequency noise ( LFN ). The profile of {N}_{\text {ot}} along the depth direction was investigated before and after D 2 annealing using LFN characteristics. It was confirmed that {D}_{\text {it}} as well as {N}_{\text {ot}} was reduced by the D 2 annealing, resulting in a reduction in power spectral density and variation.