基于巨压阻效应的高灵敏SiC纳米带压力传感器基础研究

The sensors are the “facial features” of human beenings to know about and change the natural world, which have been considered as one of the key technologies for the modernization. However, with the continuously enhanced service requirements, the sensors with high sensitivity and high stability are highly desired. These become the grand chanllege for the exploration of the next-generation sensors. In the present work, we intend to make use the unique advantage of SiC materials with the insitrinc high temperature stability and the perfect single-crystalline crystal structures of nanobelts, for the exploration of novel and efficient high-sensitivity pressure sensors. We will firstly realize the precise control on the growth and doping of single-crystalline SiC nanobelts via pyrolysis of polymeric precursors. Then, the research will be carried out to investigate the effects of sizes and doping of the SiC nanobelts on their giant piezoresistance behaviors, which leads to disclosing the relationship among the structures, doping and piezoresistance properties of the single-crystal SiC in nanoscale. Subsequently, we will systematically study the influences of the size effect, surface effect and energy band regulation of SiC nanobelts on their piezoresistance properties, and clarify the transportation behaviors of the carriers and piezoresistance effect mechanisms of the pressure sensors based on SiC nanobelts. Current work might have the profound scientific significance for the exploration of the high sensitivity and robust stability SiC high-temperature pressure sensors based on giant piezoresistive effect.

传感器是人类认识和改造世界的“五官”，是衡量现代化进程的关键技术之一。随着服役需求的不断提高，对高灵敏高稳定的传感器需求日益迫切，成为当前研发的主要困难和挑战。本项目拟利用SiC材料体系独特的高温稳定性及其单晶纳米带结构，以高灵敏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SiC单晶纳米带生长与掺杂的精细控制，揭示其结构-掺杂-压阻特性间的内在关联，实现其巨压阻效应并进行优化，大幅度提高其灵敏度。相关工作将系统评价尺寸效应、表面效应和能带调控对SiC纳米带压阻特性的影响，阐明其载流子输运特性及其压阻机理，有望实现基于巨压阻效应的高灵敏高稳定SiC高温压力传感器的研发，具有显著的科学意义和潜在的应用价值。

压力传感器在微电子机械系统器件中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纳米结构的的精细设计，然后研究SiC纳米结构的形貌、掺杂类型和异质结构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3C-SiC结构-掺杂-压阻特性间的内在关联，阐明SiC纳米结构载流子输运特性及其压阻机理，最终为SiC高灵敏压力传感器的研发提供关键支撑数据。通过有机前驱体热解工艺的系统探索和优化，实现了SiC纳米结构在形貌、掺杂类型及其掺杂浓度的可控制备，以此为基础，研究了N掺杂3C-SiC纳米带的压阻特性，其压阻系数为10.2910-11 Pa-1，压阻因子为~61.7，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N和P共掺杂3C-SiC单晶纳米线的压阻特性，实验结果表明，双掺杂SiC单晶纳米线压阻系数高达-146.3010-11 Pa-1，压阻因子为~ -877.79，显著提高nN级别力变化的探测灵敏度；研究了B掺杂3C-SiC纳米带的压阻特性，其展现出独特的负压阻特性，压阻系数高达-312.5110-11 Pa-1，压阻因子为~ -1875.1，性能远超已报道的SiC基纳米结构，对应力变化探测的灵敏度得到了进一步的提高；研究了光辐射和掺杂对SiC纳米线压阻特性的协同影响，选择N掺杂的SiC纳米线为功能单元，在功率为62.4 mW的紫外光辐照下，N掺杂的SiC纳米线的压阻系数提高至11.7910-11 Pa-1，明显高于暗场时的4.3210-11Pa-1，光场耦合有效提高SiC纳米传感器的灵敏度；研究了压电效应和掺杂对SiC纳米结构压阻特性的协同影响，构建ZnO/SiC纳米异质结为测试功能单元，ZnO纳米层厚度为20 nm时，可将N掺杂的SiC纳米线的压阻系数由6.6910-11 Pa-1提高至9.4710-11 Pa-1，压电效应耦合为高灵敏SiC纳米传感器的研究提供了新的研究思路。.项目相关工作在国际期刊上共发表SCI论文9篇，影响因子皆大于3；申请国家发明专利8项，授权8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上发表SCI收录论文8篇，其中影响因子大于3 的5 篇以上，申请国家发明专利2项以上)。