Design and modeling of III-V group semiconductor material based thin film βeta (β) voltaic cells

In this thesis study, β-voltaic devices consisting of 3H (Ti-3H tritide form) and 63Ni isotope sources with III-V group semiconductor materials have been designed and simulated. In order to design β-voltaic devices, the interaction of beta particles emitted from the beta source with different semiconductor materials was performed using CASINO software. Thus, for both 3H and 63Ni sources, the depth that beta particles can reach in semiconductor materials was determined. Using the obtained data, e-p pair production rates as a function of depth were calculated for all semiconductor materials within the scope of the study for both 3H and 63Ni sources separately. Then, different β-voltaic cell structures with different architectures such as p-n, n-p and p-i-n were designed using different combinations of semiconductor materials. The results obtained from CASINO software and the calculated e-p pair generation rates were used as input to SCAPS software, a one-dimensional device simulation program, to simulate betavoltaic devices. In betavoltaic cells consisting of different semiconductor materials and different device architectures, parameters such as layer thicknesses of junction regions, doping densities and defect densities were varied to optimize the performance of the cells through outputs such as open circuit voltage, short circuit current and device efficiency. Within the scope of the thesis study, for the first time III-V group flexible thin film β-voltaic cells have been designed and modeled. In addition, symmetric bi-facial β-voltaic cell structures were designed and theoretically modeled for the first time. A new perspective has been brought to this emerging technology