Anomalous Capacitance Induced by GIDL in P-Channel LTPS TFTs

Author

Lin, Chia-Sheng ; Chen, Ying-Chung ; Chang, Ting-Chang ; Chen, Shih-Ching ; Jian, Fu-Yen ; Li, Hung-Wei ; Chen, Te-Chih ; Weng, Chi-Feng ; Lu, Jin ; Hsu, Wei-Che

Author_Institution

Dept. of Electr. Eng., Nat. Sun Yat-Sen Univ., Kaohsiung, Taiwan

Volume

30

Issue

11

fYear

2009

Firstpage

1179

Lastpage

1181

Abstract

In this letter, a mechanism of anomalous capacitance in p-channel low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) was investigated. In general, the effective capacitance was only the overlap region and independent with the frequency in LTPS TFTs under the off state. However, our experimental results reveal that the capacitance was related with the leakage current and that it was dependent with the measurement frequencies when operated at the off-state region. The increase of the capacitance value is verified to be due to the increase of the electron capacitance originating from a gate-induced drain-leakage (GIDL) one. Nevertheless, the GIDL-induced electron capacitance can be suppressed by employing band-to-band hot electron stress.

Keywords

capacitance; leakage currents; semiconductor device measurement; silicon; thin film transistors; GIDL; Si; anomalous capacitance; band-to-band hot electron stress; electron capacitance; gate-induced drain-leakage; leakage current; low-temperature polycrystalline silicon; p-channel LTPS TFT; thin-film transistors; Displays; low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2009.2031504

Filename

5280336