An Ultralow EOT Ge MOS Device With Tetragonal HfO2 and High Quality Hf x Ge y O Interfacial Layer

Autor:	Chun-Chang Lu, Jen-Wei Cheng, Chen-Chien Li, Li-Jung Liu, Chung-Hao Fu, Kuei-Shu Chang-Liao, Ting-Ching Chen
Rok vydání:	2014
Předmět:	Tetragonal crystal system Hysteresis Materials science Band gap Diffusion Phase (matter) Electronic engineering Analytical chemistry Equivalent oxide thickness Thermal stability Substrate (electronics) Electrical and Electronic Engineering Electronic Optical and Magnetic Materials
Zdroj:	IEEE Transactions on Electron Devices. 61:2662-2667
ISSN:	1557-9646 0018-9383
DOI:	10.1109/ted.2014.2329839
Popis:	A Ge MOS device with an ultralow equivalent oxide thickness of ~0.5 nm and acceptable leakage current of 0.5 A/cm 2 is presented in this paper. The superior characteristics can be attributed to a tetragonal HfO 2 with a higher k value (k ~ 31) and comparable bandgap. In addition, a Ge MOS device with tetragonal phase HfO 2 (t-HfO 2 ) also shows a lower leakage current and better thermal stability. The mechanisms for t-HfO 2 formation may be explained by the little Ge diffusion from Ge substrate and oxygen deficiency, which are obtained by in situ interfacial layer (IL) formation and high-k processes. The IL with k ~ 13 can be formed by in situ H 2 O plasma treatment. Moreover, a Ge MOS device with the IL grown by H 2 O plasma shows smaller interface trap density and hysteresis effects due to a high composition of Ge +4 .
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::d4616343bd942b790e01e8f29ef8a263 https://doi.org/10.1109/ted.2014.2329839 Zobrazit plný text záznamu