Advanced Modeling and Characterization of the Poole-Frenkel Effect in Dielectrics and Semiconductors

经典的普尔-弗伦克尔（PF）效应是指介电体和半导体中大量的库仑吸引阱中载流子的热辐射，在电场的作用下增强。该机制导致电子材料中的电流高于理想电流，包括传统介质、Si3N4和SiO2中的漏电流；高介电常数材料（如Ta2O5和BaSrTiO3）的泄漏，这些材料在dram和mosfet中具有很大的前景；以及碳化硅（SiC）二极管的增强电流。研究的目的是探讨先进的PF效应模型和实验技术，以表征电子器件和材料中的PF传导。我们的主要目标是：(i)研究使用费米-狄拉克函数来描述陷阱种群统计的PF模型，同时仍然结合自由电子密度的玻尔兹曼近似。模拟饱和以上电压下的电流。（ii）研究该模型作为温度的函数。确定它是否预测饱和时I-V(T)曲线的收敛，正如我们早期的研究表明的那样。（iii）研究该模型对我们测量饱和和阱电离势的技术的影响。（iv）用Ta2O5制作MIS结构，测量I-V(T)曲线寻找饱和度，并验证我们的一般技术。(v)首次使用费米-狄拉克函数来描述陷阱和自由电子的居群统计。将该模型纳入商业模拟器，并模拟6H-SiC p-n二极管。本研究将增进我们对PF效应的认识，并提高电子器件中该效应建模的准确性。

The classical Poole-Frenkel (PF) effect is the thermal emission of charge carriers from Coulombic attractive traps in the bulk of dielectrics and semiconductors, enhanced by an electric field. This mechanism results in higher than ideal currents in electronic materials, including leakage currents in conventional dielectrics, Si3N4 and SiO2; leakage in high dielectric constant materials such as Ta2O5 and BaSrTiO3, which hold great promise as gate dielectrics in DRAMs and MOSFETs; and enhanced current in Silicon Carbide (SiC) diodes. The research objective is to investigate advanced models of the PF effect and experimental techniques to characterize PF conduction in electronic devices and materials. Our primary goals are: (i) Investigate a PF model using the Fermi-Dirac function to describe the trap population statistics, while still incorporating the Boltzmann approximation for the free electron density. Model the current at voltages above saturation. (ii) Investigate this model as a function of temperature. Determine if it predicts convergence of I-V(T) curves at saturation, as our earlier research suggests. (iii) Investigate the implications of this model on our technique for measuring saturation and trap ionization potential. (iv) Fabricate MIS structures with Ta2O5, measure I-V(T) curves looking for saturation, and verify our general technique. (v) Use the Fermi-Dirac function to describe both trap and free electron population statistics for the first time. (vi) Incorporate the model in a commercial simulator, and simulate 6H-SiC p-n diodes. This research will enhance our understanding of the PF effect, and improve the accuracy of modeling this effect in electronic devices.