Title :
Negatively charged deep level defects generated by Yttrium and Lanthanum incorporation into HfO2 for Vth adjustment, and the impact on TDDB, PBTI and 1/f noise
Author :
Sato, Motoyuki ; Kamiyama, Satoshi ; Sugita, Yoshihiro ; Matsuki, Takeo ; Morooka, Tetsu ; Suzuki, Takayuki ; Shiraishi, Kenji ; Yamabe, Kikuo ; Ohmori, Kenji ; Yamada, Keisaku ; Yugami, Jiro ; Ikeda, Kazuto ; Ohji, Yuzuru
Author_Institution :
Semicond. Leading Edge Technol., Inc. (Selete), Tsukuba, Japan
Abstract :
We studied the impact of Yttrium and Lanthanum incorporation into HfO2 on reliability (TDDB, PBTI and 1/f noise). They introduce smaller Weibull ß values and early failure in TDDB, with negative shift in PBTI. They are caused by the negatively charged interstitial oxygen defect generated by Yttrium and Lanthanum incorporation. The effect of Lanthanum is larger than that of Yttrium. It can be explained by the larger ion radius and molecular volume of La2O3 than Y2O3. On the other hand, they are effective in noise reduction, as an effect of interface state density reduction. The key point in fabricating low Vth and highly reliable MOSFETs is the technology for suppression of this interstitial oxygen defect generation.
Keywords :
1/f noise; MOSFET; Weibull distribution; crystal defects; hafnium compounds; lanthanum; semiconductor device noise; semiconductor device reliability; semiconductor doping; yttrium; 1/f noise; HfO2-La2O3; HfO2-Y2O3; MOSFET; PBTI; TDDB; Weibull value; interface state density reduction; interstitial oxygen defect generation; negatively charged deep level defect; positive bias temperature instability; reliability; threshold voltage adjustment; time dependent dielectric breakdown; Electrons; Hafnium compounds; Hafnium oxide; Interface states; Lanthanum; Lead compounds; Noise generators; Noise level; Semiconductor device noise; Yttrium;
Conference_Titel :
Electron Devices Meeting (IEDM), 2009 IEEE International
Conference_Location :
Baltimore, MD
Print_ISBN :
978-1-4244-5639-0
Electronic_ISBN :
978-1-4244-5640-6
DOI :
10.1109/IEDM.2009.5424407
