Blue Single Quantum Well GaN LED

ledex01.in : Blue Single Quantum Well GaN LED

Requires: Blaze/Quantum/LED Minimum Versions: Atlas 5.22.1.R

This example demonstrates how the radiative recombination models in Atlas can be used to analyze the electro-luminescence spectrum.

The objective of this example is to get the basic LED characteristics such as the I-V-L curve and EL spectrum. The input decks shows the 8 sections required to make a basic LED input file. These sections create the structure, specify the model combination and biasing, and finally plot the curves.

Mesh Generation

The first section of the input file defines the mesh and scales the WIDTH to be A/cm^2.

Region and Electrode Specification

To model the effects of strain and the piezo effect, the CALC.STRAIN , POLARIZATION and POLAR.SCALE parameters of the REGION statement can be used. These parameters will be result in an interface charge of ~1e13 cm-2, depending on the mole fraction of the active layer.

To get the E.L. Spectrum, the parameters QWELL and LED should be specified on the quantum active layer REGION statement.

The ANODE and CATHODE contacts are defined on the top and bottom of the device.

Doping Profiles

Layers 1 and 2 have a P-type doping of 1e19 cm-3. Layer 3 is the Single Quantum Well (SQW) and is undoped. Layer 4 is doped at 1e18 cm-3 N-type. All doping profiles have a uniform distribution.

Material and Models

There are three parts to this section. The first defines the MATERIAL parameters for the Recombination and Lorentz linewidth broadening factor and for the incomplete ionization. The second part defines the MODELS for the GaN regions. The K.P model is used for the band parameters as well as the FERMI model. The other MODELS statement defines the Gain and EL spectrum models for the SQW region. The CHUANG and SPONTANEOUS are specified along with LORENTZ for linewidth broadening. The third part defines the mobility.

Bias Ramp and Save Spectrum

To obtain the EL spectrum, the SPECTRUM parameter and wavelength range LMIN , LMAX and NSAMP are specified on the SAVE statement.

Plotting Curves

EXTRACT was used to calculate the the electron and hole concentration as a function of the bias. The I-V-L and EL spectrum as well as also plotted.

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.