缓冲层对二极管反向雪崩击穿耐量影响的仿真研究  

Research on Buffer Layer Effect on Ruggedness of Reverse Avalanche Breakdown of Diode

作　　者：刘修伟 关艳霞[1] 潘福泉[1] 

机构地区：[1]沈阳工业大学信息科学与工程学院,辽宁沈阳110870

出　　处：《电源技术应用》2015年第1期42-45,共4页Power Supply Technologles and Applications

摘　　要：利用SilvacoTCAD仿真软件对p＋n—n＋结构二极管在反向击穿情况下的电场分布进行了仿真分析，雪崩载流子浓度的升高改变了耗尽区的电荷密度，因此电场分布形状发生改变，当雪崩击穿电流达到一定值时，在nn＋结处出现第二个电场尖峰，从而引发双雪崩现象。双雪崩会导致负微分电阻现象发生，以致形成电流丝，造成器件损坏。为抑制nn＋结的电场尖峰的出现，在n区n＋区之间引入缓冲层，缓冲层能起到延缓nn＋结的电场尖峰的出现，从而提高二极管的雪崩击穿耐量。Silvaco TCAD simulation software is used to analyse the electric field distribution for p＋n-n＋ structure diode in the case of reverse breakdown , because of increased avalanche carrier concentration changes the electric density of the depletion region that the shape of the electric field distribution is changed, when the avalanche breakdown current reaches a certain value, there will be a second electric field spikes which can cause double avalanche phenomenon in nn ＋ junction . Double avalanche will result in a negative differential resistance occurs, resulting in the formation of current filaments which can damage the device. To curb the electric field peak appearance in nn＋ junction, introducing a buffer layer between the n- region and the n＋ areas, buffer layer can rise to delay the appearance of the tip of the electric field on the nn＋ junction, thereby improving the avalanche breakdown diode ruggedness.

关 键 词：双雪崩 电流丝 缓冲层 雪崩击穿耐量 

分 类 号：TN31[电子电信—物理电子学]