Engineering Homework Help

Using “SQ Limit Def File.def” resolve the following problems.

1. In the CdTe-base.def model, make a contour map of the efficiency versus shallow uniform acceptor density and Defect 1 total density, both on a logarithmic scale. What is the maximum efficiency of this device stack based on these calculations? Be sure to keep the ranges of values that you use physically relevant. Save a new def file with the optimized acceptor and defect1 densities.

2. Taking your optimized device from #1, now look at the effect of the back (left) contact work function. Is the performance affected by work function? If so, can you find a metal with a work function that matches your best device? Set the best left contact work function in the model and save it to the def file from #1.

3. Run a batch calculation for the CdTe_base.def device measured over a logarithmic range of light intensities and a linear range of temperatures (see batch example in the lecture). Plot the open circuit voltage versus temperature for each light intensity. Perform a linear fit through the Voc(T) data and extrapolate to 0K. What is the value of the voltage intercept at 0K? Is it light intensity dependent?

4. Take the optimized device that you saved in #2. Change the absorption model to “from model” instead of “from file”. This will allow you to run batches as a function of the band gap of the device. Run a batch calculation over the band gap energy from 0.4 eV to 3 eV in 0.05 eV steps. How close do you come to the SQ limit curve for efficiency vs band gap?

5. Take the optimized device that you saved in #2. Change the spectrum from AM1.5G to a monochromatic (e.g. 800nm) spectrum and rerun the batch from #4. What is the peak efficiency you achieve? Comment on why this is.

Use excel for all calculations and for graphs, and provide the file.

Download the latest version of the SCAPS solar cell simulation program along with the manual. It is available for free from the University of Gent, although they do require an email to get the link. Here is the home page: http://scaps.elis.ugent.be/ However, clever googling turns up the SCAPS Download page directly. Install and send a screenshot (not a phone picture of your monitor omg). Play around with it.

Please look for help in the SCAPS Manual (uploaded).

I attached the excel file and the SCAPS program as well and the SQ limit def file.def