Quantum capacitance

About: Quantum capacitance is a research topic. Over the lifetime, 954 publications have been published within this topic receiving 24165 citations.

Determination Method for Interface State Densities Adapted to Ultrathin Dielectrics

Abstract: In this paper modified Terman method for determination of interface state densities, adapted for nanosized dielectrics has been applied to the case of Al-gated MIS structures containing ultrathin (2.56 nm to 5.15 nm thick) SiO 2 dielectric layer. It has been demonstrated that modified Terman method is effective in precise determination of interface states density distributions for nannosized SiO 2 dielectric SiO 2 layers. Tails towards the band edges are not present when using this method. For all three samples a peak around 0.3 eV is observed. It corresponds to the first peak of the P b defect. Second peak corresponding to the P b defect cannot be clearly distinguished due to the presence of a peak related to Al gate.

Closed-Form Frequency Dependent Gate-to-Channel Capacitance Model for Submicron MOSFET's

Abstract: A new model of the gate-to-channel capacitance is proposed including the transmission line effects, not only for strong inversion but also for moderate and weak inversion regimes, which gives a good description of experimental capacitance curves. This is achieved by expressing the channel conductance in function of the inversion layer concentration. Quantum effects in the distribution of the inversion charge are taken into account by the introduction of a mean centroid, which is related to an effective capacitance area. This effective area is smaller than the real one due to nonuniform, surface conductivity, which is attributed to a random doping distribution giving fluctuations of the surface potential.

Sequential analysis of resonant tunneling diodes

Abstract: In recent years, it has been established that a substantial part of the current through a double barrier resonant tunneling structure is transported by sequential tunneling instead of fully coherent tunneling. The theoretical framework of sequential tunneling is especially attractive since the admittance of the device can be obtained immediately. In order to complete this model we have investigated the frequency behavior of the charging and discharging phenomena in the quantum well. All geometric capacitances and the quantum capacitance [1] have been taken into account in this model.[2]

Study and design of graphene field effect transistor for RF performance

Abstract: This paper presents the study of RF characteristics of Graphene based Field Effect Transistor (GFET). The study of characteristic curves is carried out using SILVAVO TCAD tools. The RF parameters which determines the performance of the device in the higher frequency and the effect of downscaling of the device channel length is analyzed and parameters are extracted. This work also presents the effective and novel way to model the material graphene in simulator and GFET device simulation using TCAD.

First principles calculation of the structure and quantum capacity of acidic functional groups on graphene-based capacitor

Abstract: Graphene has been much anticipated as an ideal active material of electric double layer capacitor (EDLC). However, the overall capacitance of monolayer graphene is affected by its own low quantum capacitance (Cq). This characteristics lowers most of the capacitor properties, therefore, we should concentrate on finding a solution to increase Cq value. By using density-functional theory on graphene with different functional groups, we compared the effects of functional groups on Cq and band structure. Then we found that some functional groups could change the local electric structure of graphene, and improve the Cq value of graphene at low voltage range. This should be due to the effects of electronegative atom in functional groups. As a result, functionalized monolayer graphene could have better capacitor performance in aqueous electrolytes.