Hot Carrier solar cells are a class of Third Generation photovoltaic device. For the hot carrier cell to be effective, “hot” carriers must be collected from the absorber over a very small energy range. This is so that only a small amount of their excess energy above the band edge is lost in cooling to the contact temperature. The structure required for this is an energy selective contact (ESC) to extract carriers with minimal heating of the external contacts.

Double barrier resonant tunnelling contacts are being investigated as energy selective contacts, with quantum dots providing a discrete energy level between two insulating barriers. This will give conduction strongly peaked at the discrete energy level. Work in this area is focussed on resonant tunnelling structures using quantum dots as the resonant centres which would give the required total energy filtering.

In this work, a 2 dimensional model will be developed to calculate vertical transport properties of the tunnelling current in an ideal double-barrier hetero structure, against the size and the distribution of the quantum dots. The effectiveness of the filtering in different directions of the momentum and a comparison with the quantum well resonant tunnelling can be made from the results. The QD structure is expected to have effective filtering in all the directions of momentum. As future work, the model can be extended to include the non-ideal cases, varying barrier width with constant potential well width and varying barrier potential width with constant barrier width.