Diamond is one of the most promising candidates for high power and high temperature applications, due to its large bandgap and high thermal conductivity. As a result of the growth and fabrication process of diamond-based devices, structural defects such as threading dislocations (TDs) may degrade the electrical properties of such devices. Understanding and control of such defects are important for improving device technology, particularly the reverse breakdown characteristics. Here, we show that the reverse bias current-voltage characteristics in diamond PIN diodes can be described by hopping conduction and Poole-Frenkel emission through TDs over the temperature (T) range of 323 K < T < 423 K, for typical values of the TD density found in epitaxially grown materials.

No abstract

The realization of advanced concept solar cells that circumvent assumptions inherent in the Shockley-Queisser limit depends strongly on a competition between carrier energy relaxation processes to the lattice and high energy processes that do useful work. Here we review the role of ultrafast carrier dynamics in the performance of such advanced concept devices, experimental results to date, and then present theoretical studies of such processes using ensemble Monte Carlo simulation of electrons, holes and phonons, with a particular focus on such processes in multi-quantum well systems, as well as III-V nanowires.

Diamond is considered as an ideal material for high field and high power devices due to its high breakdown field, high lightly doped carrier mobility, and high thermal conductivity. The modeling and simulation of diamond devices are therefore important to predict the performances of diamond based devices. In this context, we use Silvaco® Atlas, a drift-diffusion based commercial software, to model diamond based power devices. The models used in Atlas were modified to account for both variable range and nearest neighbor hopping transport in the impurity bands associated with high activation energies for boron doped and phosphorus doped diamond. The models were fit to experimentally reported resistivity data over a wide range of doping concentrations and temperatures. We compare to recent data on depleted diamond Schottky PIN diodes demonstrating low turn-on voltages and high reverse breakdown voltages, which could be useful for high power rectifying applications due to the low turn-on voltage enabling high forward current densities. Three dimensional simulations of the depleted Schottky PIN diamond devices were performed and the results are verified with experimental data at different operating temperatures

No abstract