Study On Characteristics Of Films Based On Near Field Microwave Microscope

The rapid development of film material technology provides a strong product support service for the development of mechanical electronics industry,aerospace manufacturing industry and biological medical instruments.But at the same time,the volume and performance of modern film products are also put forward more stringent standards.How to efficiently,quickly and accurately characterize the physical properties of new functional film materials has become a hot research field for university and research institutes.At present,the methods of characterizing the characterization of thin film samples are scanning electron microscopy(SEM)and atomic force microscopy(AFM).There are four probes in the electrical conductivity measurement.The high frequency electromagnetic characteristics are characterized by resonant cavity method and network parameter method.The network parameter method analysis methods include time domain method,free space method,transmission reflection method and so on.The samples characterized by resonant cavity method usually have certain requirements on the size and size.It is difficult to test the electromagnetic parameters for nano materials.Although the four probe method can measure the conductivity of the film sample,but tip collision will cause the non-repaired damage to the sample.The SEM characterization is limited,only can describe the surface morphology of the sample.Therefore,we urgently need a characterization system that can characterize the morphology with nondestructive characterization of materials.The near field scanning microwave microscope uses the electromagnetic reaction between the probe and the sample to record the variation of the quality factor of the ?/4 and the offset of the resonant frequency.Then the physical parameters such as the conductivity,the quality factor and the surface profile of the sample are obtained by means of other characterization methods,and the metallic film materials and the graphene thin film materials are nondestructive and nondestructive.The electromagnetic characteristics of the material solve the problems encountered by other characterization methods.In this paper,the principle of the near field microwave scanning system and the testing method is described.By improving and optimizing the test steps,a hundred nanometers of metal film and graphene film are prepared and complated the calibration work with SEM,AFM and step meter.Then,the surface morphology and electromagnetic properties of the thin films were analyzed by SEM,four probe method and near-field scanning microwave microscope.The near-field microwave testing method has the advantages of simple test,high sensitivity,high resolution and no loss to sample testing.At the end of this paper,the prospect of the application of the near field scanning microscope is put forward.It is believed that the non-contact and nondestructive detection technology of the near field microwave scanning microscope will play an important role in the industrialization of graphene.