文档介绍：摘要摘要本文就SiO,/SiC界面质量对n沟SiC MOSFET性能的影响做了深入的研究: 从碳化硅材料的晶体结构出发分析了碳化硅材料中杂质的不完全离化,采用 SiCMOS反型层薄层电荷数值模型,研究了杂质不完全离化对P型6H—SiC MOS C-V 特性的影响。分析结果表明不完全离化对siC MOSFET的影响主要集中在亚阈区。建立界面念密度的指数分靠模型,用数值方法较为详细的分析了界面念电荷对n沟MOSFET器件闽值,漏电流,跨导和场效应迁移率的影响。/分析结果显示界面态电荷不仅使闽值电压增大,而且还会导致器件漏电流减小,跨导和场效应迁移率降低,模拟结果能对实验现象做出很好的解释ij明确指出碳化硅器件的反型层迁移率和实验测定的场效应迁移率不能等同,并给出了以上二者的比值与界面态密度的定量关系。本文还就如何提高SiC/Si0:界面质量做出了有益的尝试:用3UCVD方法在 SiC衬底上得到SiO:层。。关键词:碳化硅j二氧化硅j界面态垒堕竺!! Abstract In thispaper,the effectofinterface properties ofSi02/SiC on performances of n-channel SiCMOFET arestudied systematically: plete ionization ofimpurity inSiC isanalyzed based on thecrystal structure plete ionization ofimpurity on C·Vcharacteristics ofp-type 6H—SiC MOS isresearched based on Charge-Sheet model forSiC MOS inversion results of the analysis show thattheimpact of plete ionization on SiC MOSFET ismore notable insubthreshold region than instrong inversion region. The effect of interface state charges on the threshold voltage,drain current, transconductance and ofn—channel SiCMOSFET isanalyzed with numerical method by establishing themodel oftheinterface state density exponential study shows that interface state charges notonly increase thethreshold also lower theMOSFET transconductance,drain current and field-effect mobility,which can well explain the results of ispointed that inversion-layer mobility iSdifferentfrom field-effectmobility for a relationship has been established between theratiooftheexperimentally·determined mobility tOthe actualinversion-layer carriermobilityand interface states. Inthispaper,it has been attempted how tOimprove interface is expected thatthe Si02 layergrown on SiC wafer by means of 3UCVD Canimprove the definiteconclusions have notstillbeen obtained. key words:Silicon carbide Silicon dioxide Interface state 第一章绪论第一章绪论§