Effects of the Self-Heating on 3D Cylindrical LED Structure

ledex06.in : Effects of the Self-Heating on 3D Cylindrical LED Structure

Requires: Device 3D/Giga 3D Minimum Versions: Atlas 5.28.1.R

This example shows the effect of the self heating on 3D structure with cylindrical three dimensional mesh.

The objective of this example is to obtain the lattice temperature distribution in the three dimensional structure at operating bias.

This example has 3 parts.

The first part demonstrates the cylindrical mesh generation method. In this case only half the device is simulated to save simulation time.

The R.MESH statement is used to specify radial locations and spacings. Similarly, the A.MESH statement is used to specify angular locations and spacings in degrees. Finally, the Z.MESH statement is used to specify the locations and spacings in the Z direction.

For 3D cylindrical devices, the REGION statements define regions in cylindrical coordinates using the parameters A.MIN , A.MAX , R.MIN , R.MAX and , Z.MIN and Z.MAX.

Similarly, the ELECTRODE statements can define an anode electrode as a ring on the top surface and the cathode electrode as a plate on the bottom of the device.

Next, DOPING statements are used to define uniform dopant concentrations in each region.

Next, the MODEL statement is used to specify the models to be used in the example. The recombination models are selected for Shockley-Read-Hall (SRH), Auger (AUGER) , and radiative (OPTR) recombination.

Also, Fermi-Dirac statistics, FERMI , and concentration dependent mobility, CONMOB , are selected.

Lattice temperature simulation, LAT.TEMP , with Joule heat, JOULE.HEAT , and generation recombination heat, GR.HEAT sources are selected.

The MATERIAL statement is used to specify the alignment of the conduction band offsets using the ALIGN parameter.

A thermal contact is specified using the THERMCONTACT statement. Here a heat sink boundary is simulated using the sink temperature, EXT.TEMP , and the thermal conductance, ALPHA , in W/(cm2*K).

The METHOD statement is used to specify some specific numerical methods to be used to help obtain solutions for self-heating simulations.

Next, after obtaining an initial zero bias solution. The PROBE, LOG and OUTPUT statements are used to specify output characteristics to be collected that are of particular interest to this simulation.

Next, a bias ramp is performed to place the LED at the operating bias.

Finally, TonyPlot and the EXTRACT statement are used to present the simulation results.

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