Selective energy contacts for hot carrier solar cells

The concept of the hot carrier cell is to absorb a wide range of photon energies and to separate the resulting “hot” carriers before thermalisation within a narrow range of energies onto external electrodes.Proof of concept of selective energy contacts has been demonstrated for double barrier resonant structures using Si quantum dots for resonant energy levels using current–voltage measurement with and without optical excitation and conductive atomic force microscopy.Si quantum dot resonant tunnelling structures are fabricated by thin film deposition followed by Si solid state precipitation in a SiO2 matrix, with the size uniformly controlled by the layer thickness. Further characterisation and approaches to optimization are discussed.