How to Set Up and Run the MOSFET Simulator
- Create a directory in your root directory named
"matlab". I'll refer to your root directory as ~/ from now on.
- Create a file named startup.m in ~/matlab/
- Copy the following lines in startup.m:
- Create a directory of your choice to run the program in, say
- 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 ./
- When you now run the program from here, the output data files will be
created in this directory. To run the program:
- While still in this directory, tap matlab and run
- In MATLAB, type
to run the plotting program.
- 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
- Choose what you want to plot from the plotting options menu to the
right after it loads the file.
Things to Do
- 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).
- If you give the command
that plot should appear.
- 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.
- 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