转移石墨烯内部缺陷及其MEMS压阻式微压传感器研究

Study on internal defects of transferred graphene and its MEMS piezoresistive micropressure sensor

石墨烯受力后变形可以产生压阻效应,利用这个原理,制作石墨烯微压传感器。但是在实验中,发现石墨烯会产生诸多缺陷,进而影响石墨烯的压阻效应。因此,该文采用拉曼确认转移后SiO2基底上双层石墨烯的褶皱形成和缺陷形成很少。同时,采用XPS确定石墨烯在制作传感器过程中表面的有N、O等污染原子吸附。AFM表面图像发现转移后的表面很平整。并采用MEMS工艺完成石墨烯微压传感器的制作,利用3D打印的腔体完成传感器的封装,通过气体微亚泵对传感器施加压力,得到压力测量量程在0~3 kPa,电阻温度系数极低。该研究可为石墨烯作为压阻传感器提供更细致的理论基础和技术指导。

A graphene based piezoresistive micro-pressure sensor is proposed,due to the principle that there is piezoresistive effect of graphene if graphene has deformation after loading.But Many defects will be produced and these have great influence on the piezoresistive property of graphene.Raman is used to confirm that there is little fold formation and defect formation in the bilayer graphene on the SiO2 substrate after transfer.At the same time,XPS is utilized to determine the adsorption of N,O and other contaminated atoms on the surface of graphene in the process of making the sensor.AFM surface images show that the transferred surface is flat.Moreover,the graphene micro-pressure sensor is manufactured by MEMS technology,and the 3D printed cavity is used to package the sensor.Pressure is applied to the sensor through the gas micro pressure pump,and the pressure measurement range is 0-3 kPa,with extremely low resistance temperature coefficient.This study provides a more detailed theoretical experimental basis and technical guidance for graphene as a piezoresistive sensor.