Separation of Channel Backscattering Coefficients in Nanoscale MOSFETs

Yan

IEEE Electron Device Lett.

et al. 2007

The MOSFET backscattering theory relies on a socalled "k B T " layer. In this letter, we adopt two different approaches to examine the temperature dependencies of the width spanned by this critical zone. First of all, a 55-nm channel length n-MOSFET is extensively characterized at three temperatures of 233 K, 263 K, and 298 K while undergoing a parameter decoupling/transformation process. A unique relationship is straightforwardly created and is comparable with that in the literature: The width of the "k B T " layer is proportional to the square root of temperature. The case of 77 K is also projected. Other corroborating evidence is a Monte Carlo particle simulation conducted on an 80-nm-long silicon conductor with the "k B T " layer's width proportional to the temperature in the high field region. Without adjusting any parameters, the backscattering theory is shown to work well for the demonstrated temperatures down to 77 K.

Section: Methodsmentioning

confidence: 99%

Temperature-Oriented Experiment and Simulation as Corroborating Evidence of MOSFET Backscattering Theory

Yan

IEEE Electron Device Lett.

et al. 2007

Journal of Vacuum Science &Amp; Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena

“…This capacitance reduction does not allow us to calculate EOT from C-V g characteristics. Therefore, as well as surface passivation layer characterization, efforts to decrease J g such as GeON formation followed by high-k deposition, 3,[9][10][11] systematic study of gate stack interface characterization, 28,29 will play important roles to realize germanium based MOS technology.…”

Section: Geon Stability Against Oxidation Ambientmentioning

confidence: 99%

“…[5][6][7][8] Several studies suggested that intermixing of high k and GeO 2 and abrupt interface of high k / GeO 2 cause poor electrical property of metal/high-k / GeO 2 / Ge gate stack structure. [9][10][11] Therefore, forming more stable passivation oxide layer on germanium surface is an important issue. To solve this problem, germanium oxynitride ͑GeON͒ is known as a good passivation layer on germanium surface.…”

Section: Introductionmentioning

confidence: 99%

Physical and electrical properties of plasma nitrided germanium oxynitride

Sugawara¹,

Sreenivasan²,

McIntyre³

2006

The physical and electrical properties of plasma nitrided germanium oxynitride (GeON) and silicon oxynitride (SiON) layers are studied. In this study, two kinds of plasma nitridation process were utilized to form oxynitride layers. High pressure remote inductive coupled plasma and low pressure radial line slot antenna (RLSA) plasma provide radical dominant and ion dominant plasma nitridation processes, respectively. X-ray photoelectron spectroscopy results show different properties of GeON layers based on each plasma nitridation process. The remote (radical) plasma nitridation forms water soluble nitrogen-germanium bonding, and RLSA (ion) plasma nitridation forms water resistant nitrogen-germanium bonding. Although hydrogen containing plasmas or ion dominant plasma process can incorporate high amount of nitrogen into oxynitride layers, such process is accompanied by water insoluble suboxide formation and charging damage. Using p-type metal oxide semiconductor (MOS) capacitors, basic electrical properties of GeON and SiON films were also studied. Approximately four order magnitude higher gate leakage current was observed on GeON MOS capacitor, which results in capacitance reduction and a large dissipation factor at high gate voltage.

IEEE Electron Device Lett.

“…Within an experimental methodology that considers a temperaturedependent backscattering coefficient, it has been demonstrated that it is difficult to yield the temperature dependence of the quasi-ballistic parameters as the gate length decreases [6]. Furthermore, the indirect method based on the current-voltage (I-V ) fitting [7] or assumption [8] has been used to extract the source/drain series resistance R sd needed to evaluate effective carrier velocity v ef f , and the inversion charge density at the top of the barrier in a short device was indirectly obtained from that in a large device [9].…”

Section: Introductionmentioning

confidence: 99%

Comprehensive Study of Quasi-Ballistic Transport in High-$\kappa$/Metal Gate nMOSFETs

Sagong

Kang²,

Sohn

et al. 2011

We study quasi-ballistic transport in nanoscale high-κ/metal gate nMOSFETs based on radio-frequency (RF) S-parameter analysis. An RF S-parameter-based simple experimental methodology is used for direct extraction of device parameters (i.e., L ef f , R sd , and C inv ) and the effective carrier velocity v ef f from the targeted short-channel devices. Furthermore, an analytical top-of-the-barrier model, which self-consistently solves the Schrödinger-Poisson equations, is used to determine the ballistic carrier velocity v inj at the top of the barrier near the source. Based on the results of the experimental extraction and analytical calculations, backscattering coefficient r sat and ballistic ratio BR sat are calculated to assess the degree of the transport ballisticity for nMOSFETs. It is found that conventional high-κ/metal gate nMOSFETs will approach a ballistic limit at an effective gate length L ef f of approximately 7 nm.Index Terms-Ballistic transport, carrier velocity, high-κ, radio frequency (RF).