標題: | Junction and Device Characteristics of Gate-Last Ge p- and n-MOSFETs With ALD-Al2O3 Gate Dielectric |
作者: | Cheng, Chao-Ching Chien, Chao-Hsin Luo, Guang-Li Lin, Ching-Lun Chen, Hung-Sen Liu, Jun-Cheng Kei, Chi-Chung Hsiao, Chien-Nan Chang, Chun-Yen 電子工程學系及電子研究所 Department of Electronics Engineering and Institute of Electronics |
關鍵字: | Al2O3;forming gas annealing (FGA);gate-last metal-oxide-semiconductor field-effect transistor (MOSFET);germanium;high-k gate dielectrics;junction diode |
公開日期: | 1-八月-2009 |
摘要: | In this paper, we investigated the characteristics of Ge junction diodes and gate-last p- and n-metal-oxide-semiconductor field-effect transistors with the atomic-layer-deposited-Al2O3 gate dielectrics. The magnitudes of the rectifying ratios for the Ge p(+)-n and n(+)-p junctions exceeded three and four orders of magnitude (in the voltage range of +/-1 V), respectively, with accompanying reverse leakages of ca. 10(-2) and 10(-4) A . cm(-2), respectively. The site of the primary leakage path, at either the surface periphery or junction area, was determined by the following conditions: 1) the thermal budget during dopant activation, and 2) whether forming gas annealing (FGA) was employed or not. In addition, performing FGA at 300 degrees C boosted the device on-current, decreased the Al2O3/Ge interface states to 8 x 10(11) cm(-2) . eV(-1), and improved the reliability of bias temperature instability. The peak mobility and on/off ratio reached as high as 225 cm(2) . V-1 . s(-1) and > 10(3), respectively, for the p-FET (W/L = 100 mu m/4 mu m), while these values were less than 100 cm(2) . V-1 . s(-1) and ca. 10(3), respectively, for the n-FET (W/L = 100 mu m/9 mu m). The relatively inferior n-FET performance resulted from the larger source/drain contact resistance, higher surface states scattering, and lower substrate-doping concentration. |
URI: | http://dx.doi.org/10.1109/TED.2009.2023948 http://hdl.handle.net/11536/149809 |
ISSN: | 0018-9383 |
DOI: | 10.1109/TED.2009.2023948 |
期刊: | IEEE TRANSACTIONS ON ELECTRON DEVICES |
Volume: | 56 |
起始頁: | 1681 |
結束頁: | 1689 |
顯示於類別: | 期刊論文 |