p-n结二极管结区边界附近的交流电特性

基于p-n结二极管的理想工作状态的基本假定，推导了二极管在交流电下工作时其基区和p-n结分界面附近上的时间常数与二极管空间尺寸、扩散长度、载流子寿命和外加交流电频率等的依赖关系.结果发现高频和低频两种状态下二极管各类特征参量对时间常数的作用不一样.低频条件下，二极管的时间常数由材料本身来决定，与外加电流频率无关.高频情况下，时间常数则与半导体材料性质无关，只由外加交流电的频率来决定.

Boundary alternating current characteristics of an ideal p-n junction diode

According to basic assumptions about the ideal operating state of p-n junction diode, deducing the relation of the time dependence of constant on the parameters such as diode size, diffusion length, carrier lifetime and alternating current frequency etc. at the base and near the p-n junction interface when diode is working under the applied alternating current. From the results,we discovered that in the two kinds of states of low and high current frequencies, the diode characteristics act on the time constants differently. In the low frequency state, the time constant is related to the material characteristics but not to applied current frequency. But in high frequency state, the time constant has no relation with the material characteristics, and was only related to the applied current frequency.