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

• 2D Diffusion & Implantation

Victory Mesh

• 2D Meshing

Victory Device

• 2D Simulator
• 2D REM

This example demonstrates how an SEU strike in a power MOSFET can create a high transitory gate field sufficient to rupture the gate oxide. Experiments have shown that a transitory breakdown field across the gate oxide that only lasts for picosecond time scales, is sufficient to rupture the gate causing permanent damage to the device.

A gate rupture event is dependent on both the device bias and the LET of the SEU strike. The bias that creates the most sensitive conditions for a gate rupture event occurs when the field across the gate oxide from the gate bias is in the same direction as the additional field from the induced charges from the SEU event. When this condition occurs, the existing field across the device from the gate bias is re-enforced by the additional field created by the SEU induced charge track, thus minimizing the LET required from the SEU strike to cause a gate rupture event.

The example creates a power MOSFET structure using the Victory Process simulator. Circular symmetry is then used for the device simulations, where the centre of the cylindrical device is at X=0 (the left hand side of the structure).

An SEU strike with an LET of 37.2 (corresponding to a Bromine Ion), is simulated, with the strike occurring at the centre of the device (X=0). At the time of the SEU strike, a bias of -13.9 volts is applied to the gate and 30 volts on the drain. This bias condition creates a near critical condition close to that required for a gate rupture event to occur.

The gate oxide field was probed near the strike, such that gate oxide field versus time could be plotted before, during and after the SEU strike. After the SEU strike occurs, this critical reversed bias condition results in a peak gate oxide field that increases by over 3 times the field from just the DC bias condition alone.

The evolution of the hole concentration distribution was also monitored at 5, 50 and 150 picoseconds after the strike. The drain current was simulated over a longer time span. For completeness, the breakdown voltage and unsaturated threshold voltage (for Vd=0.1 volts) were also simulated.

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