Morab Seema, Sundaram Manickam Minakshi, Pivrikas Almantas
College of Science, Health, Engineering and Education, Murdoch University, Perth, WA 6150, Australia.
Materials (Basel). 2023 Jun 29;16(13):4691. doi: 10.3390/ma16134691.
Charge transport characteristics in organic semiconductor devices become altered in the presence of traps due to defects or impurities in the semiconductors. These traps can lead to a decrease in charge carrier mobility and an increase in recombination rates, thereby ultimately affecting the overall performance of the device. It is therefore important to understand and mitigate the impact of traps on organic semiconductor devices. In this contribution, the influence of the capture and release times of trap states, recombination rates, and the Lorentz force on the net charge of a low-mobility organic semiconductor was determined using the finite element method (FEM) and Hall effect method through numerical simulations. The findings suggest that increasing magnetic fields had a lesser impact on net charge at constant capture and release times of trap states. On the other hand, by increasing the capture time of trap states at a constant magnetic field and fixed release time, the net charge extracted from the semiconductor device increased with increasing capture time. Moreover, the net charge extracted from the semiconductor device was nearly four and eight times greater in the case of the non-Langevin recombination rates of 0.01 and 0.001, respectively, when compared to the Langevin rate. These results imply that the non-Langevin recombination rate can significantly enhance the performance of semiconductor devices, particularly in applications that require efficient charge extraction. These findings pave the way for the development of more efficient and cost-effective electronic devices with improved charge transport properties and higher power conversion efficiencies, thus further opening up new avenues for research and innovation in this area of modern semiconductor technology.
由于半导体中的缺陷或杂质产生的陷阱,有机半导体器件中的电荷传输特性会发生改变。这些陷阱会导致电荷载流子迁移率降低和复合率增加,从而最终影响器件的整体性能。因此,了解并减轻陷阱对有机半导体器件的影响非常重要。在本论文中,通过数值模拟,使用有限元法(FEM)和霍尔效应法确定了陷阱态的捕获和释放时间、复合率以及洛伦兹力对低迁移率有机半导体净电荷的影响。研究结果表明,在陷阱态的捕获和释放时间恒定的情况下,增加磁场对净电荷的影响较小。另一方面,在恒定磁场和固定释放时间的情况下,通过增加陷阱态的捕获时间,从半导体器件中提取的净电荷随着捕获时间的增加而增加。此外,与朗之万复合率相比,在非朗之万复合率分别为0.01和0.001的情况下,从半导体器件中提取的净电荷分别高出近四倍和八倍。这些结果表明,非朗之万复合率可以显著提高半导体器件的性能,特别是在需要高效电荷提取的应用中。这些发现为开发具有改进的电荷传输特性和更高功率转换效率的更高效、更具成本效益的电子器件铺平了道路,从而进一步为现代半导体技术领域的研究和创新开辟了新途径。