ABSTRACT
In this chapter, the authors discuss the principles of the quantum well solar cell and ways in which the design of the test devices can be improved to increase the overall power conversion efficiency while preserving the enhancement due to the quantum wells. They reports for the first time recent results obtained with new samples in which changes of geometry have doubled the efficiency in comparison with published test samples. A new approach has recently been suggested (Barnham and Duggan 1990) in which Multi-Quantum-Well or Super-Lattice systems are used as the active absorbers in the intrinsic region of a p-i-n solar cell. In order to maximise the efficiency enhancement available in a quantum well solar cell the additional current must be increased with least cost to the output voltage. The authors estimate that the optimisation of device structures reported has more than doubled the overall efficiency in comparison with the test results.
