Correlation between inversion layer mobility and surface roughness measured by AFM

Linearity and mobility degradation in strained Si MOSFETs with thin gate dielectrics

“…These Si channel surface asperities can be characterised by the root-mean-square roughness and the correlation length [26]. Surface roughness can be modelled as variations in oxide thickness, hence carriers transiting along the channel will be perturbed by a change in potential that is proportional to the average roughness amplitude [26,27]. According to the Fermi golden rule, the scattering rate is proportional to the square of the perturbation potential resulting from the surface roughness [28].…”

Characteristics of Facing Target-Sputtered Amorphous InGaZnO Thin Films as the Active Channel Layer in Transparent Thin Film Transistor on Polymeric Substrate

“…Also, in the fabrication procedure of bottom-gate a-InGaZnO TFT, the surface of SiO 2 gate dielectric layer has been exposed to multiple processing before the a-InGaZnO channel layer deposition, which may roughen the channel-dielectric interface. Hence, the Downloaded by [Umeå University Library] at 09:40 20 November 2014 [14,15] may be occurred in the bottom gate a-InGaZnO TFT. Figure 5 shows the transfer characteristics and gate leakage current (I GS ) for a-InGaZnO TFTs with a W/L ratio of 10 for V DS = 6 V. Both a-InGaZnO TFTs represent the n-channel characteristics because electrons are generated by low negative V GS .…”

Oxide thickness variation induced threshold voltage fluctuations in decanano MOSFETs: a 3D density gradient simulation study

“…with a given correlation length and RMS height [9,12]. Assuming isotropy and performing 2D Fourier transform in radial coordinates, it is straightforward to obtain the power spectra S(q) corresponding to the above correlation functions:…”

“…During discretization, the spacing between atomic layers in the (001) direction is taken to be 0.271 nm. Typically in state-of-the-art MOSFET devices, ≈ 0.3 nm and ≈ 10-15 nm [12,13], although both values can vary an order of magnitude as indicated above. In this work we alter these parameters in order to investigate their impact on device characteristics.…”