SiC低维纳米材料压阻特性及其性能剪裁

In present work, directed by the investigation of high-temperature pressure sensors with excellent properties, we will firstly realize the precise control on the growth and doping of single-crystalline 6H-SiC nanowires via pyrolysis of polymeric precursors. Then, the research will be carried out to investigate the effects of sizes and doping of the 6H-SiC nanowires on their piezoresistance behaviors, which leads to disclosing the relationship among the structures, doping and piezoresistance properties of the single-crystal 6H-SiC in nanoscale sizes. These works are aimed for the growth of 6H-SiC nanowires with precisely tailored structures and doping, which might be promising to provide the key source materials for the exploration of novel high-temperature pressure sensors with high performance. Subsequently, we will study systematically the influences of size effect, surface effect and energy band regulation of 6H-SiC nanowires on their piezoresistance properties under room- and high-temperatures, and clarify the transportation behaviors of the carriers and piezoresistance effect mechanisms of the pressure sensors based on 6H-SiC nanowires. Current work could accomplish the tailoring of the piezoresistance performance of SiC nanowires, and provide some scientific data and basic theories for the exploration of robust high-temperature pressure sensors with high sensitivity and stability.

本项目拟以高性能高温压力传感器研发为导向，以有机前驱体热解为材料制备手段，实现6H-SiC纳米线生长与掺杂的精细控制；深入揭示6H-SiC纳米线尺寸、掺杂类型和浓度等与其压阻特性之间的相互关系并进行优化，建立纳米尺度下6H-SiC结构-掺杂-压阻特性间的内在关联，为SiC高温压力传感器的研发提供关键支撑材料。相关工作将系统评价尺寸效应、表面效应和能带调控对6H-SiC纳米线的室温和高温压阻特性的影响，阐明SiC纳米线室温和高温的载流子输运特性及其压阻机理，实现SiC纳米线高温压力传感器的性能剪裁，为高灵敏高稳定的高温压力传感器研发提供一定的科学数据和理论依据。

压力传感器在石油化工、地热勘探、医疗、汽车等领域具有广泛的应用前景。本项目以获得高灵敏高稳定SiC压力传感器研发为目标，首先通过有机前驱体热解工艺的精细控制，实现SiC低维材料的的精细设计，然后研究SiC低维材料的尺寸、掺杂类型和浓度等与其压阻特性之间的相互关系并进行优化，建立纳米尺度下SiC结构-掺杂-压阻特性间的内在关联，阐明SiC纳米线室温和高温的载流子输运特性及其压阻机理，最终为SiC高温压力传感器的研发提供关键支撑材料。我们通过有机前驱体热解工艺的系统探索和优化，实现了SiC低维材料在掺杂类型、掺杂浓度及其形貌上的可控制备，以此为基础，研究了N掺杂n型单晶SiC纳米线的压阻特性，其压阻系数为0.75～7.710-11Pa-1，压阻因子为4.5～46.2，高于传统的SiC块体材料和薄膜材料，能够实现nN级别力变化的高灵敏探测；研究了B掺杂p型SiC单晶纳米线的压阻特性，其展现出独特的负压阻特性，压阻因子为-53～-620.5，对应力变化探测的灵敏度得到了进一步的提高；研究了掺杂和形貌对SiC低维材料压阻特性的协同影响，优化选择B掺杂的SiC超薄纳米带为功能单元，获得了压阻因子高于1800的高灵敏压阻特性，为SiC材料体系迄今国内外报道的最高值。.项目相关工作在国际期刊上共发表SCI论文18篇，其中影响因子大于3的15篇(含影响因子大于7的6篇)；申请国家发明专利9项，授权7项，圆满完成本项目拟定的研究内容和目标 (拟定的目标：预计在国外学术期刊和国际会议上发表SCI收录论文16～18篇，其中影影响因子大于3 的10 篇以上，力争发表影响因子大于7 的论文2～3 篇，申请国家发明专利2～3项)。