4.1 Devices Used

Device 1
The device which was used for most simulation experiments is depicted in Fig. 4.1. It has an effective gate-length of $130 \, \mathrm{nm}$, a gate-oxide thickness of $3 \, \mathrm{nm}$, and a silicon-film thickness of $200 \, \mathrm{nm}$. With a p-doping of $\mathrm{N_A} = 7.5 \times 10^{17} \, \mathrm{cm^{-3}}$ the device is partially depleted. The Gaussian n-doping under the electrodes has a maximum of $\mathrm{N_D} = 6 \times 10^{20} \, \mathrm{cm^{-3}}$.

Figure 4.1: Sketch of the simulated SOI MOSFET including symbolic compact devices. Important effects are SHOCKLEY-READ-HALL generation/recombination (SRH) and impact-ionization (II).

Device 2
To compare Device 1 to an equivalent MOSFET a second device has been investigated which has a small body contact added to pin the potential of the body to fixed values.

Device 3
This device has been generated by MINIMOS 6, the device simulator with which the Monte Carlo simulations have been performed. It has a gate-length of $150 \, \mathrm{nm}$. Gate-oxide and silicon-film thickness as well as the doping concentrations have the same values as in Device 1.

Device 4
For comparison and verification an SOI device has been modeled after the $90 \, \mathrm{nm}$ "Well-Tempered" MOSFET [57] using the doping profiles available, including the super steep retrograde (SSR) channel doping and source/drain halo-doping. To achieve a partially depleted device a substrate doping of $\mathrm{N_A} = 7.5 \times 10^{17} \, \mathrm{cm^{-3}}$ has been assumed, and the substrate thickness has been limited to $200 \, \mathrm{nm}$.

M. Gritsch: Numerical Modeling of Silicon-on-Insulator MOSFETs PDF