Athena/Atlas Simulation of an NPN BJT

bjtex10.in : Athena/Atlas Simulation of an NPN BJT

Requires: Athena/S-Pisces
Minimum Versions: Athena 5.22.3.R, Atlas 5.28.1.R

This example demonstrates how to use combination of several Athena runs in 1D mode and Atlas to simulate the electrical characteristics of a vertical NPN bipolar transistor. This example shows:

  • Four Athena simulations in 1D mode of various doping distributions in a 1D NPN bipolar structure
  • Athena-Atlas interface for 1D doping profiles
  • Ic and Ib extraction versus Vbe (Gummel Plot)

Athena process simulation in 1D mode is taken as the starting point for this simulation. P+ and n+ contact implants and final anneal are added at the very end.

The input file is run four times with different steps commented out. As a result, four doping profiles in different vertical sections of the NPN device are obtained. The structure file names correspond to areas where the vertical sections are taken.

When all four Athena simulations are completed DeckBuild switches simulation to Atlas where mesh and electrodes are set. After that, doping profiles from all four 1D structures are used to build 2-D doping in Atlas. Uniform antimony (buried layer) and arsenic (epi layer) profiles are imported from bjtex10_1.str . Afterwards emitter doping is specified in the area between x=0 and x=1 using phosphorus component of the bjtex10_1.str profile. The parameter ratio.lat represent lateral diffusion during emitter formation. Base boron doping is specified in the area between x=0 and x=5 from bjtex10_2.str . P+ contact boron doping and N+ phosphorus doping under collector contact are imported from corresponding Athena structure files.

Then a standard Gummel plot simulation with Atlas is then performed. This is described in detail in the first example in this section.

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.