3D Trench Shape Effect on IV and BV Characteristics

sicex10.in : 3D Trench Shape Effect on IV and BV Characteristics

Requires: Victory Process, Victory Mesh, Victory Device
Minimum Version Victory Process 7.30.4.R, Victory Mesh 1.4.6.R, Victory Device 1.14.1.R

By default Victory Process and Device run on just one processor. To ensure better perfomance on your computer the following simulation condition simflags="-P all" could be specified in the go statement starting Victory Process or Device. This means that all processors available will be used. If you want to use a smaller number of processors you can substitute "all" with a desired number, e.g. simflags="-P 4".

The following example demonstrates the effect of the shape of a trench on IV and BV characteristics.

The 3D layout-driven structure is created using Victory Process. 3D device simulation is done using Victory Device built-in extended precision numeric.

In this example we compare 3 different structures. One fully Manhattan (i.e right angle layout and trench) versus 2 structures one having rounded layout and another one having rounded layout and angled trench.

Aluminum implantation is simulated in 1D (to save simulation time) in Athena using Monte Carlo implantation before being imported in the 3D structure using the PROFILE statement in Victory Process.

The 3D structure is meshed to a full 3D Delaunay mesh using Victory Mesh. Different options are available in order to optimize the mesh under the gate and at the p/n junction. This 3D refinement is fully automatic.

The 3D structure is then loaded in Victory Device. The default 3D Delaunay discretization method combined with a parallelized iterative solver set by PAM.MPI statement in Victory Device allow good convergence, speed and accurate results.

Victory Device automatically sets the optical axis downwards toward the SiC surface. This is important for anisotropic models such as anisotropic impact ionization, which treat one direction (downwards, along the optical axis in this case) differently than the others.

We can clearly see the effect of the trench shape on the IDVG and BV characteristics. Indeed a known "hump" effect is observed on the IDVG characteristic especially on the device with full Manhattan shape. However this parasitic effect is removed with the device using rounded layout and angled trench.

BV simulation reveals that the breakdown voltage can be increased by 30% using rounded layout and angled trench due to impact ionization not occurring anymore only at the corner of the trench.

To load and run this example, select the Load button in DeckBuild > Examples. This will copy the input file and any support files to your current working directory. Select the Run button in DeckBuild to execute the example.