Conformal layers for solar cell simulation

@aalam @mmahpeykar Dear both of you, hope, you are doing fine. I need some help regarding the following issue. I have designed a conformal solar cells as you can see here: Structure
For you to know, I already optimized the structures by using optical fdtd modeling. Now, I want to perform the electrical simulations. For that, I need some help. As you see, the absorber layer is also conformal, therefore I don´t understand very well, how can I accurately do the electrical simulation. usually, in the case of flat absorber layer, I do extract the generation profile from 3D optical simulation, and input into 2D electrical simulation. But for this case, how can I extract the generation profile (G) only from the conformal absorber layer, and how can I simulate right dimension in 2D electrical simulation? N.B: as you know that 3D electrical simulation takes too much time and large memory. Any experience that you you have in related to this kind of optical and electrical solar cells modeling, I will be grateful if you can share with me. If you have scripts and/or suggestions, you can also share with me.Thank you so much!! I am looking forward to hearing from you. Best, MJM


As long as the materials adjacent to your absorbing layer are not semiconductors in the electrical simulation, you should be able to setup the generation analysis group in FDTD so that it covers the entire absorbing layer (and partially the adjacent layers) and in DEVICE, simply align the imported generation with the structure since any existing extra absorption in adjacent layers coming from FDTD (for example by the metal contacts) won’t be considered in the electrical simulation when they are not a semiconductor. You can also consider one unit cell of the structure in the simulation to increase speed similar to the following example:

Hope this helps!

@mmahpeykar Thanks for your help. Now I am following your suggestions. Anyway, I will come to you if I get some problems in doing electrical simulation. Best, MJM

Dear @mmahpeykar , I simulated a device simulation in planer configuration for initial study. However, It is giving some errors, specially i.e,: 1. Initialization failed to converge electrostatic potential update, and 2. The error code is 9002, the process number is 0. I went thorough some tutorials of Lumerical but still unable to solve the problem. Can you please look into my file? Here I attached the simulation file for your look. Perovskite_Cell.ldev (7.4 MB)

Thanks for your effort!! Best, MJM

I found the following issues in your simulation:

  1. The number of solver iterations (50) was not high enough (in Advanced tab of the CHARGE solver). This will prevent the solver to converge to a solution and that’s why you were getting the error.
  2. The optical generation object (purple box) was not aligned with the structure (it was located on the edge of the simulation region) and so was not included in the simulation. So I moved it to the middle to be included in the simulation. Also it is not as wide as the structure itself which is not physical because it means that light absorption only happens at the center of the structure. Plus, since the charge simulation is 2D, the generation data better be uniform in the third dimension (by averaging) to ahve more realistic simulation. This has been demonstrated in a few of our solar cell examples.
  3. The simulation region does not need to be this wide since the device is planar and uniform in all directions. So to make the simulation faster, you can shrink the simulation region in in X direction and the results would be the same since the charge transport is in Y direction mostly.
    A modified version of your file with above mentioned modifications is attached.
    Perovskite_Cell.ldev (7.5 MB)

Thanks @mmahpeykar, but unfortunately, your modified version is also giving me the same errors. Did you able to run the modified version simulation successfully? Sorry for bothering you! Best, MJM

Are you using the latest version of DEVICE?

Yes, I am using the version of 2018 installed when the license was renewed. Thanks

The latest version is 2019 with version number 7.3.1809

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