期刊论文

Tan, Y.-L.

中文

发光学报

1000-7032

2008

29

2

337-341

本校为其他机构

利用正向交流(ac)小信号方法对GaN发光二极管的电容-电压特性进行测量,可以观察到GaN发光二极管中的负电容现象.利用LED串联等效电路对表观电容和表观电阻进行了测量,表观电阻-正向电压曲线出现了一个极值点.通过对相关文献分析,提出负电容现象的根本原因是在较高的正偏下微分电容dQdU＜0;推论出pn结的微分电容先随正向偏压的增大而急剧增大,当出现复合发光后随正向偏压的增大而减小,直到随正向偏压的增大而出现负值;正向偏置电压较大时,结电导电流的变化率根据I-V特性曲线取极大值,此时微分电容由于强复合效应已快速变小,表观电阻有极大值;得到了表观电阻极大值表达式.表观电阻与正向电压曲线的...

The forward current-voltage characteristic and forward capacitance-voltage characteristic measurings are the most important methods to study the forward electricity characteristic of GaN light-emitting diodes. We can use the forward alternating current (ac) small signal method to measure the capacitance-voltage characteristic of the GaN light-emitting diodes. Some value of GaN light-emitting diodes parameters can be deduced from capacitance-voltage characteristic. The negative capacitance phenomenon of GaN light-emitting diode can be observed by using this method. Measuring the apparent capaci...