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 Process
- 3D Structure Editor
- 3D Diffusion & Implantation
Victory Mesh
- 3D Meshing
Victory Device
- 3D Simulator
This example demonstrates the creation of a buffered super junction LDMOS.
Super junctions are used in LDMOS structures to greatly increase the breakdown voltage of small geometry devices by allowing the drain depletion region to spread in two dimensions instead of one at higher drain voltages (the additional direction being laterally across the super junction). The net result is that the drain voltage can now be spread across a much greater total distance than would otherwise be the case, which greatly lowers the field at the drain and therefore increases the breakdown voltage.
Another advantage of super junction technology is that the n doped stripes in the super junction can be doped to higher concentrations because the important depletion distance is now the lateral distance between the super junction stripes (determined largely by the technology node) rather than the full depletion width of the drain. Higher doping yields lower on resistance, increasing current drive over a standard construction design with a similar breakdown voltage.
The buffered super junction device takes this technology one step further by including an additional n-doped buffer layer under the super junction, which increases the breakdown voltage to even higher values by expanding the depletion region in the remaining third dimension which is down into the depth of the substrate. This example demonstrates the effectiveness of this approach as it has an electrical gate length of only 2.5um but its breakdown voltage is 95 volts.
Images
