摘要
对传统的电容-电压(C-V)、电流-电压(I-V)测量方法和我们自建的表征方法测量得到的蓝光发光二极管(LED)正向特性的结果做了详细的对比分析,发现传统测量方法得到的电学参量是不够精确的。但是传统C-V方法得到的表观电容以及我们自建方法得到的结电容在大电压和低频率下都表现出了明显的负值,该实验结果与经典肖克莱理论相冲突。此外,我们精确地得到了负的结电容以及结电导随电压和频率变化的经验表达式。这将为半导体二极管的正向电学特性的理论研究提供实验基础。
At large forward bias voltage, the accurate electrical properties of semiconductor GaN-based blue light-emitting diode （LED） with multiple-quantum well （MQW） structure prepared by metal organic chemical vapor deposition （MOCVD） were measured by single capacitance-voltage （C-V） method and single current-voltage （I-V） method,as well as our self-built method,respectively. After comparing the experimental results,we find that a single C-V or I-V method cannot be considered as an accurate characterization metbod,because they can only reflect the apparent characteristics rather than the junc- tion parameters of LEDs. However, both the apparent capacitance Cp measured by C-V method and the junction capacitance C measured by our self-built method display obvious negative value at large forward bias and low frequency, which is in conflict with the well known Sbockleyrs p-n junction theory and mod- el which only include increasing diffusion capacitance and certainly no negative capacitance. Furthermore, the ideal factors of LEDs obtained from both our method and I-V method far exceed the traditional theo- retical values. Finally, the accurate expressions of junction capacitance and junction conductance on volt- age and frequency are obtained. These results will provide an experimental basis for the study of semi- conductor diode junction theory.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2013年第4期663-668,共6页
Journal of Optoelectronics·Laser
基金
国家自然科学基金(60876035,11204209,50901050,11004148,11004149)资助项目
关键词
发光二极管(LED)
负电容
电导
P-N结
light-emitting diode （LED） negative capacitance
conductance p-n junction
作者简介
E-mail：fengliefeng@tju．edu．cn冯列峰（1980-），博士，副教授，主要从事半导体器件光电特性的研究．
