DC Characterization

optoex02.in : DC Characterization

Requires: S-Pisces/Luminous
Minimum Versions: Atlas 5.22.1.R

The first example involves characterization of steady state characteristics of the device, and demonstrates extraction of DC currents as a function of optical source power. It also demonstrates the use of multi-spectral sources. The source spectrum is described in the file "optoex02.spec".

The first section of the input file specifies that the mesh and device structure is taken from the previous example. The second section of the file sets the same material models that were specified in the previous example.

The third section of the input file specifies the optic source. In this example the source originates 1 micron above the device and is directed normal to the front surface of the device. The source spectrum is described in the file "optoex02.spec". This spectrum is sampled at 5 discrete samples between the wavelengths of 0.5 and 0.8 microns.

The fourth section of the file sets up the initial operating bias for the simulation. In this case an operating bias of 2.0 volts is chosen.

The last section of the input file specifies that the optical source intensity will be ramped from 0 to 1 W/cm^2. During this ramp, steady state currents are extracted and saved in the log file.

The results are displayed by TonyPlot. The first figure shows several curves. The first, source photo current, is the equivalent current what would be observed if all the light from the source were detected. The second curve, available photo current is the equivalent current that would be observed if all the light absorbed were converted to terminal current. The difference between the source and available photo currents is due to part of the light passing all the way through the device. The third curve is the cathode current. By taking the ration of the cathode current with the source photo current, the quantum efficiency as a function of source intensity is plotted in the second figure. Here the device quantum efficiency is about 91% and is relatively independent of source intensity.

To load and run this example, select the Load example button in DeckBuild. This will copy the input file and any support files to your current working directory. Select the run button to execute the example.