Band-Structure and Quantum Effects on Hole Transport in p-MOSFETs

Abstract

Using a Monte Carlo method, we investigate hole transport in ultrasmall p-channel Si MOSFETs with gate lengths of 25 nm. The device simulator couples a 2D Poisson solver with a discretized 6 × 6 k.p Hamiltonian solver that includes the effect of the confining potential and provides the subband structure in the channel region. In addition, carriers in the source and drain regions are treated as quasi 3D particles and the band-structure information is included by solving for the eigenenergies of a more compact 6×6 k.p Hamiltonian.

Subband structure and effective mass of relaxed and strained Ge (110) PMOSFETs

“…In this paper, the effective mobility for Ge (1 1 0) PMOSFETs has been calculated by using the Momentum Relaxation Time (MRT) approximation according to the Kubo-Greenwood formulation [11,13]. The scattering mechanisms included in the calculations contain the acoustic and optical phonons, the surface roughness scattering, and the impurity scattering.…”

“…Once the relaxation times for the different scattering mechanisms have been determined, the hole mobility formula for each subband, shown as follows, is calculated according to the KuboGreenwood formula [11,13] …”

Effect of conduction band nonparabolicity on the dark current in a quantum well infrared detector

“…14 The choice for k 0 in solids at low temperature is usually the temperature-independent Thomas-Fermi wave vector to produce the best known theoretical calculation for the dynamic local field correction. In order to include a relatively smaller wave vector cutoff at finite temperature, we have used the temperature-dependent Debye-Hückel wave vector 35 in our calculation which is defined as k 0 = ͱ 2e 2 n 2D / ϱ k B T. Since k 0 has a large wave vector cutoff, G͑q t , T͒ becomes negligibly small.…”

Efficient simulation of hole transport in strained Si and SiGe on insulator inversion layers

“…Until recently only the stochastic MC algorithm was used for solving the Boltzmann transport equation (BTE) within the subbands of a hole inversion layer [1,2]. For accurate simulations of the low-field mobility and the distribution function over a large energy range the MC method is very inefficient.…”