Solar Cells Simulation Using Lumerical Tools (Part 4 - Lumerical Charge-setting)
Introduction
In this section, we will continue with the numerical chart. Previously, we simulated the heat part using a heat solver to extract the temperature profile. Now, we will focus on the charge simulation.
Numerical Chart Overview
The numerical chart includes various components such as:
- Solver
- Doping Section
- Boundary Condition
- Different Sources and Monitors
- Simulation Region
We use the same materials as in the previous section, including silicon, aluminum, silicon nitride, SiO2, silver, and air. The geometry remains consistent with the previous simulations.
Charge Simulation Setup
In the charge simulation region, right-click on the charge section and select "Edit Object" to view settings similar to the heat simulation region. The simulation is set to 2D with normal boundaries on the X and Y axes. The background material is air, and the geometry spans from 0 to 10 micrometers in the X direction and around 3.8 micrometers in the Y direction.
Simulation Parameters
- Simulation Type: 2D
- Boundary Conditions: X and Y closed
- Background Material: Air
- Geometry: 0 to 10 micrometers (X), 3.8 micrometers (Y)
Solver Settings
The solver type is set to steady state to simulate a steady-state condition, including heat generation from the heat solver. The mesh setting uses triangular shapes, and the simulation outputs include thermal Q and T, band structure, charge, J, JP, NP, and more.
Doping Configuration
In the doping section, we can add different types of dopants such as constant, diffusion, implant, and impulse. For example, to add a constant dopant:
- Select "Add Object" to create a new dopant object.
- Right-click on the new object and select "Edit Object".
- Choose the dopant type (N or P) and set the concentration.
For this simulation, the substrate is P-type with a concentration of 2E+16.
Diffusion Doping
For N++ diffusion between silver, copper, and silicon:
- Geometry: X span 2.8 micrometers, Y span 0.4 micrometers
- Junction Width: 0.4 micrometers
- Distribution Function: Error function
- Reference Concentration: 1E+19
Source and Monitor Configuration
We inject two data files into the numerical charge: one from the solar generation and another from the temperature profile. These can be imported through the optical generation and heat import settings.
Boundary Conditions
Boundary conditions include base and emitter settings. For the emitter:
- Analysis: Steady state
- Sweep Type: Single sweep
- Force Ohmic: True
For the base material (aluminum), the sweep type is set to range, changing the voltage from 0 to 0.47 volts with 15 simulation points.
Surface Recombination
There are four surface recombination settings, with high recombination values for silicon-aluminum and silicon-silver interfaces.
Simulation Execution
After setting up the simulation, we can run it to observe the results. The monitors include charge monitors, electric band structure, current, and temperature. The simulation is coupled to include both electric and heat generation effects.
Conclusion
With all configurations in place, the simulation is ready to run. We can visualize the results and analyze the charge distribution and other parameters.
For further details, please refer to the next video in the series.
Solar cells simulation using Lumerical tools (Part 4 - Lumerical Charge-setting) So, let's continue with the numerical chart. In the previous section, we simulated the heat part, using a heat solver and extracting the temperature profile. Now, we will continue with the numerical chart.
Here, you see the chart. In the chart section, we have different parts, such as solver, doping section, boundary condition, sources, monitors, and simulation region. We have the same material as in the previous section in the heat part.
So, we have silicon, aluminum, silicon nitride, SiO2, silver, silicon, and air. The geometry is the same as before, with a silicon base, our emitter, and SiO2 on top.
In the charge simulation region, if we right-click on the charge part, right-click on the charge section, and edit object, we can see the same settings as in the heat simulation region. Our simulation is 2DZ normal, with the boundary of X and Y normal.
We have X and Y selected as closed, with the background material as air. The geometry of our section starts from zero to 10 micrometers in the X direction and around 3.8 micrometers in the Y scale. In the charge part, we need to inject some dopant.
In the dopant part, we can see a constraint, diffusion, implant, and impulse. We will describe the differences between them in another video. For now, let's focus on the P type substrate, which is our semiconductor. We can select N or P and set the concentration of our doping.
For the P type, we will select P and set the concentration to 2E 16. For the N++ region between silver, copper, and copper, silver, copper, and silver, and silver, copper, and silicon, we can select diffusion.
We have a geometry section where we can set the X-axis to 2.8 and the Y span to 0.4 micrometers.
Our dopant is the N type, and our junction width is 0. 4. Our distribution function is an error function, with a concentration of 0.4 and a reference concentration of 1e plus 19. Now, we need to select the application domain volume type, which should be "select all domain." For the P side, we have a green rectangular region.
To see this region, we need to slide or select partitions. For the P++ region, we can see the green rectangular region between aluminum and silicon. We inject two files, a math file for the solar data and another for the temperature data.
The temperature comes from the heat solver, and the solar data comes from the G that we generate in the numerical FD TD. We can import this source by selecting "optical" and then "generation" and "edit object" to select the generation planner math.
For the boundary condition, we have a base and an emitter. For the emitter, we select the steady state and a single sweep. We need to ensure that the force ohmic is true. For the base material, we have a suit type of range, changing the range from zero to 0.47 volts with 15 numbers.
We have four surface recombination options. For silicon, aluminum, and silicon silver, the surface recombination is high. Now, everything is ready, and we can run the simulation.
Regarding the monitors, we have different monitors like charge monitors, electric band structure, current, and temperature. We will use different kinds of monitors in the next videos. So, let's start the simulation. Run.
