Every software package contains a full set of examples suitable for that version and are installed with the software. If you see examples here that are not in your installation you should consider updating to a later version of the software. These examples can be used by beginners and advanced users for product evaluation, teaching purposes, and self-training.
Required Modules
Victory Device
- 2D Simulator
This example demonstrates the IV and BV simulations of an Implantation-and-Epitaxial MOSFET (IEMOSFET) based on the following reference:
S. Harada et al., “4.3 m-ohm.cm2, 1100 V 4H-SiC Implantation and Epitaxial MOSFET, ” Material Science Forum, Vols. 527-529 (2006), pp. 1281-1284.
This paper investigates the effect of a nitrogen implantation in the surface of the lightly doped drain region, which is the N-type electrical doping connection to the main vertical drift region at the bottom of the device where the drain contact is located. In the deck, the peak doping concentration is set to the optimal value of 1e17 /cm3 described in the paper.
For wide bandgap semiconductors, it is often necessary to use extended precision when simulating the device in the “off-state “, such as when simulating breakdown. In this example, 128-bit precision is used, which is specified in the SIMFLAGS option of the GO statement at the beginning of the input deck. This is not necessary for the “on-state ” I-V curves.
The MESH statement can be used to define the width of the device. To convert the simulated currents to the unit of amps/cm2 used in the paper, the WIDTH needs to be set to 1.0526e7 (um), since the device length in the X-direction is 9.5 um (1e8 (um2) / 9.5 (um) = 1.0526e7 (um)).
Device engineers cannot ignore the effect of the high density of SiO2/SiC interface states as it often dominates various device characteristics such as threshold voltage and carrier mobilities. In most published SiC MOSFET device simulations, the typical interface state density is as high as 1e14 /cm2/eV at the band edge and drops to a nearly constant value of 2e11 /cm2/eV throughout the rest of the bandgap by more than 0.5 eV away from each band edge. These interface states are modelled by the INTDEFECTS statement.
The high density of interface states, effectively turns off the channel, naturally creating a normally off (enhancement mode) device with a high threshold voltage. To bring the Vth down to an acceptable level, an N-type buried channel implantation, with a surface donor concentration as high as 1.2e17 /cm3 is proposed in the paper.
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