摘要
光导开关（PCSS）在暗态耐压测试中耐压值低于理论值。根据GaAs材料特性，分析了暗态下光导开关的击穿机理。指出碰撞电离与电流控制负微分迁移率交应是导致开关击穿的直接原因。使用Silvaco半导体仿真软件对模型进行了模拟计算，结果表明温度显著影响电场、载流子浓度分布，引起碰撞电离等将就加剧，造成器件耐压值偏低。仿真结果与实验值基本相近，室温下耐压水平为33-40kV/cm。光导开关击穿特性与温度密切相关，改善光导开关散热条件可提高开关耐压水平。
Breakdown happens during the test of photoconductive switch（PCSS）without laser trigger.The breakdown phenomenon in GaAs photoconductive switch is analyzed.Impact ionization and current-controlled negative-resistance（CCNR）effect are the direct causes for the breakdown.Model is built and the simulation of current-voltage characteristics of PCSS at different temperatures is performed by the Silvaco suite.It is found that the rising of temperature dynamically changes the distribution of electrical field and carrier concentration,enhances the impact ionization and CCNR effect high enough and decreases the breakdown threshold.Simulated results agree with the experimental results：breakdown voltage is in 33-40kV/cm at room temperature.It is concluded that breakdown of PCSS is closely related to the device tmperature.Higher breakdown voltage can be achieved by better heat sink for PCSS.
出处
《激光与光电子学进展》
CSCD
北大核心
2008年第12期41-45,共5页
Laser & Optoelectronics Progress
基金
中国工程物理研究院科学技术基金(20060434)资助项目
关键词
光导开关
击穿
Silvaco模拟
温度
photoconductive switch
breakdown
Silvaco simulation
temperature
