低场低能区金刚石内载流子飞行时间的蒙特卡洛模拟

金刚石是一种重要的宽禁带半导体材料,对金刚石内载流子输运过程的研究将有助于了解金刚石用作各种电子器件的潜能。利用Monte Carlo模拟方法,研究了在低场低能区金刚石内载流子的飞行时间。在模拟中考虑了抛物线型能带模型和声学声子散射机制,以及样品对光的吸收和载流子在Brillouin区边界的Bragg反射。通过模拟,得到了低场低能区金刚石材料内载流子的飞行时间分布,并与相关的实验结果进行了比较分析,验证了该模拟模型的正确性。研究结果表明,在低场低能区,金刚石材料内主要的散射机制是声学声子散射。在研究金刚石材料内载流子的迁移输运问题时,可以采用较为简单的抛物线型能带模型,但在研究薄样品中的载流子输运时应当考虑材料的光吸收对初始载流子分布的影响,而且在场强较高以及样品厚度较大时,应当考虑载流子在Brillouin区边界的Bragg反射。

Monte Carlo Simulation of the Flight Time of Carriers in Diamond under Low Electric Field and Low Energy Region

Diamond is one of the most important wide-band-gap semiconductor materials,and the study on the migration transport process of carriers in diamond can help to find out the potential application of diamond in different kinds of electronic devices and to know the material characteristics of diamond more clearly.The flight time of carriers in diamond under low electric field and low energy region is studied through Monte Carlo simulation method.The Monte Carlo simulation method is based on parabolic band model(i.e.nearly free electron approximation band model)and acoustic phonon scattering mechanism.The light absorption in diamond and Bragg reflection at the first Brillouin Zone boundary are considered in the simulation.The flight time distributions of holes in diamond under low electric field and low energy region are obtained through the Monte Carlo simulation,and compared with the reported experimental results.The simulation results are in agreement with the reported experimental results,which verifies the accuracy of the Monte Carlo simulation model.The simulation results shows that the acoustic phonon scattering mechanism is the dominant scattering mechanism in diamond under low electric field and low energy region.The simulation results also show that the relative simple parabolic band model can be considered when the migration transport process of carriers in diamond is studied,but the influence of light absorption in materials on the initial distributions of carriers should be considered when the migration transport process in thin sample is studied,moreover,the Bragg reflection of car-riers at the first Brillouin Zone boundary should be considered when the intensity of electric field is relatively strong and the thickness of the sample is relatively large.