Modeling and Simulation of Triple Junction Solar Cells

Multi-junction solar cells are devices composed of many layers of diverse materials with varying physical properties. Understanding the operation and design of such devices is challenging because of this diversity. To support these efforts, the computer modeling and simulation study is an essential tool. The principles of two main steps in a study, conceptual modeling and simulation modeling, are presented to show their importance in dealing with many materials and their properties. Conceptual modeling deals with establishing physical mathematical models representing the physics of material behaviour. The physical models have parameters whose values are dependent on the material; often parameter models are required to establish the parameter values. Simulation models are the representation of these conceptual models within software. Examining the Sentaurus software products shows that many conceptual models are integrated within the software; proper selection of physical models must be made and parameters defined for the materials used in the device being studied. When considering new materials for improving solar cell design, typically only parameters are set for existing physical models, but it is sometimes necessary to revise the models and modify such software. Band gap modeling of dilute nitrides, in particular InGaAsN demonstrates the importance of considering conceptual modeling and how software must be capable of adapting new simulation physical and parameter models.