Charge-transport models are usually developed by first finding an appropriate density of states (DOS) which is extracted from experimental data. For organic materials, two of the more common ones include the Gaussian density of states and the exponential density of states (EDOS). This article will focus on the latter. Charge-transport models which employ an EDOS have been extensively researched, and many articles are still being published. However, from an analytical point of view, only approximate mathematical expressions for the charge carrier density are ever used. This, in general, forces a charge-transport model to be valid only within a limited temperature range. This article illustrates a more mathematically exact way to handle an organic semiconductor whose DOS can be represented by an exponential function.

通常通过首先找到适当的状态密度（DOS）来开发电荷传输模型，该状态密度是从实验数据中提取的。对于有机材料，最常见的两种包括状态的高斯密度和状态的指数密度（EDOS）。本文将重点讨论后者。已经广泛研究了使用EDOS的电荷传输模型，许多文章仍在发表。然而，从分析的角度来看，仅使用了关于电荷载流子密度的近似数学表达式。通常，这迫使电荷传输模型仅在有限的温度范围内有效。本文介绍了一种数学上更精确的方法来处理其DOS可通过指数函数表示的有机半导体。