Entity

Time filter

Source Type

Tsukuba, Japan

Tsunomura T.,Robust Transistor Program | Yano F.,Robust Transistor Program | Nishida A.,Robust Transistor Program | Hiramoto T.,Robust Transistor Program | Hiramoto T.,University of Tokyo
Japanese Journal of Applied Physics | Year: 2010

The origins of the threshold voltage (VT) variability of n-type field-effect transistors (NFETs), which have larger VT variability than p-type fieldeffect transistors (PFETs), are investigated using the Takeuchi plot and by intentionally changing process conditions. The process conditions investigated in this study are the polarity of polycrystalline silicon (poly-Si) gate electrodes, fluctuations of gate oxide thickness and gate oxide/ substrate interface, and channel stress. It is confirmed by experiments that these process conditions negligibly affect VT variability in NFETs. This result does not contradict our previous result that channel profile nonuniformity is the major origin of the larger VT variability in NFETs than that in PFETs. © 2010 The Japan Society of Applied Physics. Source


Tsunomura T.,Robust Transistor Program | Nishida A.,Robust Transistor Program | Hiramoto T.,Robust Transistor Program | Hiramoto T.,University of Tokyo
Japanese Journal of Applied Physics | Year: 2010

The property of metal-oxide-semiconductor field-effect transistors' (MOSFETs) threshold voltage (VT) variability at high temperature is investigated by evaluating the device matrix array test element group (DMA-TEG). It is revealed that VT variation is lower at high temperature than at room temperature, and that VT at high temperature has a strong correlation with VT at room temperature. The normal property of VT variability both at room and high temperatures is validated using the normal probability plot. The decrease in VT variation at high temperature stems from the reduction of the channel depletion layer width (Wdep). The temperature dependence of VT variation is evaluated using the Takeuchi plot, the VT variation normalization method. It is revealed that the change in BVT, the parameter of VT variation in the Takeuchi plot, is very small with varying temperature. © 2010 The Japan Society of Applied Physics. Source


Tsunomura T.,Robust Transistor Program | Kumar A.,University of Tokyo | Mizutani T.,University of Tokyo | Nishida A.,Robust Transistor Program | And 7 more authors.
Japanese Journal of Applied Physics | Year: 2011

The properties of drain current variability in field-effect transistors (FETs) at high temperature are experimentally investigated. It is found that the on-state drain current (ION) at high temperature has a strong correlation with ION at room temperature and that there is no anomalous ION change from room temperature to high temperature. It is also found that ION variability at high temperature is smaller than that at room temperature. The origin of the decrease in ION variability with increasing temperature is analyzed by the decomposition method developed in our previous work. It is clarified that the decrease in the current-onset voltage component plays a dominant role, especially in the saturation region. Moreover, it is also clarified that thermal excitation of carriers suppresses current-onset voltage variability, and ultimately the current-onset voltage component of ION variability with increasing temperature. © 2011 The Japan Society of Applied Physics. Source


Tsunomura T.,Robust Transistor Program | Kumar A.,University of Tokyo | Mizutani T.,University of Tokyo | Nishida A.,Robust Transistor Program | And 7 more authors.
Applied Physics Express | Year: 2010

The origin of larger on-state drain current (/ON) variability in n-type field-effect transistors (NFETs) than that in p-type field-effect transistors (PFETs), is investigated by evaluating FETs fabricated using 65nm technology. It is found that the larger /ON variability in NFETs is caused by not only the larger threshold voltage component but also the larger current-onset voltage component of the /ON variability in NFETs. Moreover, it is experimentally confirmed that /ON variability of NFETs can be reduced by the halo carbon co-implantation through the reduction of threshold voltage and current-onset voltage components of the /ON variability in NFETs. © 2010 The Japan Society of Applied Physics. Source

Discover hidden collaborations