Simulation of a Band-to-Band Tunneling Diode

quantumex23.in : Simulation of a Band-to-Band Tunneling Diode

Requires: Atlas
Minimum Versions: Atlas 5.28.1.R

This example demonstrates the capability of a TCAD simulation for non-local band-to-band tunneling (BTBT) at low to ultra-low voltages.

This example is related to the IEEE T-ED publication: T. A. Jokinen and S. McNamara, "Band-to-Band Tunneling Diode for Ultralow-Voltage Applications," IEEE Transactions on Electron Devices, vol. 64, no. 6, pp. 2702-2706, June 2017, and to the Silvaco Simulation Standard 2017 article "TCAD Simulations of TFET and Tunneling Diode".

This gives an example of using the BBT.NONLOCAL and QTREGION model to study forward and reverse tunneling current in a degernerately-doped Silicon diode at room temperature (300K), and lowering the doping concentation so that the voltage hump (negative differential resistance) in forward bias is eliminated.

The deck uses the LOOP statement to loop commands in DeckBuild.

The LOOP is used to create three similar BTBT diodes with the only difference being the doping concentrations on each side of the junction. The BTBT diodes are designed with a fine mesh. For tunneling to occur in the simulation, the junction is overlayed with a quantum region. This quantum region is defined by the statement: QTREGION . This creates quadrilateral that can be connected together to form a non-planar tunneling junction.

The model BBT.NONLOCAL is specified on the MODELS statement to use the non-local tunneling model.

The simulation should be done using 80-bit precision, using the option:

simflags="-80"

The structure file of each device in equilibrium is saved, and can be viewed in Tonyplot . You can view the band diagrams and other information about the device.

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.