Yoon Young Jun, Lee Jae Sang, Kang In Man, Lee Jung-Hee, Kim Dong-Seok
Korea Multi-Purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju 38180, Korea.
School of Electronics and Electrical Engineering, Kyungpook National University, Daegu 41566, Korea.
Micromachines (Basel). 2020 Dec 12;11(12):1100. doi: 10.3390/mi11121100.
In this work, Gallium Nitride (GaN)-based p-i-n diodes were designed using a computer aided design (TCAD) simulator for realizing a betavoltaic (BV) cell with a high output power density (P). The short-circuit current density (J) and open-circuit voltage (V) of the 17 keV electron-beam (e-beam)-irradiated diode were evaluated with the variations of design parameters, such as the height and doping concentration of the intrinsic GaN region (H and D), which influenced the depletion width in the i-GaN region. A high H and a low D improved the P because of the enhancement of absorption and conversion efficiency. The device with the H of 700 nm and D of 1 × 10 cm exhibited the highest P. In addition, the effects of native defects in the GaN material on the performances were investigated. While the reverse current characteristics were mainly unaffected by donor-like trap states like N vacancies, the Ga vacancies-induced acceptor-like traps significantly decreased the J and V due to an increase in recombination rate. As a result, the device with a high acceptor-like trap density dramatically degenerated the P. Therefore, growth of the high quality i-GaN with low acceptor-like traps is important for an enhanced P in BV cell.
在这项工作中，使用计算机辅助设计（TCAD）模拟器设计了基于氮化镓（GaN）的p-i-n二极管，以实现具有高输出功率密度（P）的β伏特电池（BV）。随着设计参数（如本征GaN区域的高度和掺杂浓度（H和D））的变化，评估了17 keV电子束（e-beam）辐照二极管的短路电流密度（J）和开路电压（V），这些参数会影响i-GaN区域的耗尽宽度。高H和低D由于吸收和转换效率的提高而改善了P。H为700 nm且D为1×10 cm的器件表现出最高的P。此外，还研究了GaN材料中的本征缺陷对性能的影响。虽然反向电流特性主要不受诸如N空位等施主类陷阱态的影响，但Ga空位诱导的受主类陷阱由于复合率的增加而显著降低了J和V。结果，具有高受主类陷阱密度的器件使P急剧退化。因此，生长具有低受主类陷阱的高质量i-GaN对于提高BV电池中的P很重要。
