P型4H-SiC少数载流子寿命的研究

Study on minority carrier lifetime of P type 4H-SiC

为了更好地了解P型4H-SiC的电学特性,评价其晶体质量,利用激光和微波技术作为非接触、非破坏性测量半导体特性的一种工具,详细描述了该测试方法和实验装置,讨论了高温退火前后晶片中少数载流子寿命的变化,并用LabVIEW对测试数据进行了拟合。结果表明:高温退火能提高载流子寿命,并且实验数据与拟合结果较符合。说明了微波光电导衰减法(μ-PCD)是一种测试少子寿命的快速、有效方法,对研究半导体材料性能具有重要意义;同时,研究高温退火条件下少子寿命的变化,对提高其材料的电性能也具有重要意义。

To better understand the P-type 4H-SiC electrical properties and evaluate the crystal qualities,laser and microwave techniques were studied as tools for non-conductive and non-destructive characterization for semiconductors,and the testing methods and experimental equipment were also described in detail.The lifetime changes of minority carrier before and after annealing were discussed,and the testing data were fitted by LabVIEW.The results show that high-temperature annealing can increase the minority carrier lifetime of the crystal,and the experimental data and fitting results are in good agreement.Therefore,microwave photoconductive decay method is convenient and efficient for measuring minority carrier lifetime,which is significant to examine the properties of SiC materials.The study of carrier lifetime change under high-temperature annealing is also significant to improve the electrical properties of silicon carbide materials.