How to Set Up and Run the MOSFET Simulator


  1. Create a directory in your root directory named "matlab". I'll refer to your root directory as ~/ from now on.
  2. Create a file named startup.m in ~/matlab/
  3. Copy the following lines in startup.m:
    mydir='/afs/glue.umd.edu/home/enee/grad/dilli/pub/enee694/hws/mosfet/';
    P=path;
    path(P,[mydir 'matlabDD'])
  4. Create a directory of your choice to run the program in, say ~/mosfetsim
  5. Go into that directory and copy the input file and the doping profile file from Dr. Goldsman's account:
    >cp /pub/neil/694/devices/LSI025/input_DD025 ./
    >cp /pub/neil/694/devices/LSI025/after_ext10.dat ./
  6. When you now run the program from here, the output data files will be created in this directory. To run the program:
    >/pub/neil/694/bin/DD input_DD025
  7. While still in this directory, tap matlab and run matlab
  8. In MATLAB, type
    >>plotHD
    to run the plotting program.
  9. In the plotting window that appears, click on "File" that is at the end of the menu bar (the one with no letters underscored) and choose "solution.dat"
  10. Choose what you want to plot from the plotting options menu to the right after it loads the file.

Things to Do


  1. First, change the Vg_start, Vg_end, and Vg_step values, plus the related Vd_* values, that can be found in the DC_BIAS portion of the input file--the first portion, in fact. After it's done running, go in MATLAB and load ids_x.dat. The first column there is the Vg values; the second is the Vd values, and the sixth column is the corresponding Id values. Using that file, plot the Id vs Vd characteristics for different values of Vg. (ids_x.dat is comprised of the columns V_g, V_d, V_source, V_body, I_source, I_drain and I_substrate, respectively).
  2. If you give the command
    >>plotids('ids_x')
    that plot should appear.
  3. After that, set Vg_start and Vg_end to the same value (ex. 2.0) and Vd_start and Vd_end to the same value (ex. 0.6) to obtain the solution.dat at that specific point. That way, you will obtain the data you'll examine in more detail for question 2 using the plotHD program in MATLAB.
  4. Don't forget to look at 2-D crossection plots; especially the plots of carrier concentrations at the surface (i.e. y=0) at different voltage values allow you to watch the progress of the pinch-off visually. To obtain a 2-D crossection plot, select "2D" button under the title "Type" and select the y position you want using the railer below, and click "PLOT".