| In recent years,the in-situ technology of electron microscopy has become a hot research area at home and abroad.On one hand,it inherits the advantages of high space and time resolution of conventional electron microscopy,On the other hand,we can introduce many different physical factors into the electron microscopy,such as the electric current,magnetic field,mechanical stress,heat and so on.We can observe the structure and physical properties of materials or devices in real-time and microscopic dimensions,discover and put forward a lot of new theories,and constantly improve and enrich people's awareness.From the current development trend of electron microscopy in-situ research both at home and abroad,the transition from single physical in-situ research equipment to multi-physiacal in-situ research equipment is inevitable.The reason is that the actual use of materials and devices is located in a complex environment,the research environment as far as possible with the actual situation is the ideal experimental conditions pursued by researchers.In this paper,scanning electron microscopy(SEM)and transmission electron microscopy(TEM)were used as experimental platforms.We have designed and manufactured a series of SEM/TEM in-situ stages for different physical functions.In-situ multi-physics coupled fields have been applied to materials of different dimensions and scales.We have gained a new understanding about matericals between its structure and performance which conventional experiments can not get.The main research contents are summarized as follows:First of all,we developed a SEM stage that can be used to change the temperature from 20 ? to 500 ? continuously,1 square centimeter.Based on the nanomanipulator of Lanzhou University,an in-situ performance measurement platform has been build which can explore materials' force,heat and electrical properties in the same time.1D SnPb nanometer solder with a melting point about 180 ? was prepared by electrochemical deposition and template method.1D SnPb nanometer solder can also be used to observe the melting process and detect the performance of the instrument.Second,we have upgrated the original electromagnetic holder,and using a closed loop design that effectively reduces leakage.Based on the distance between the pole and pole of the TEM,the transmission magnetism of the transmission electron microscope can be applied to the sample plane with a continuous magnetic field which can change from-300 Oe to +300 Oe,and two kinds of electrical signals can be provided.Eliminating the magnetic field of vertical direction due to the objective lens,building a non-environmental magnetic field interference magnetic transport test platform for the low-dimensional magnetic materials and single device.The 1J85-type Permalloy sheet was prepared by Focus Ion Beam(FIB)technique.The domain wall was moved and rotated under the horizontal magnetic real-time,and detected the performance of the instrument.In the third,we have upgrated the original in-situ electric field TEM holder up to 12 electrical signals,which is suitable for different size samples.The holder's top is designed with a replaceable miniature Printed Circuit Board(PCB)to effectively reduce the difficulty of sample load and unload.Because of it,we can also process the sample by the FIB technique.On one hand,it can be achieved 12 kinds of electrical signals,on the other hand,loaded about 2 T magnetic field of vertical direction.Combined the Lorentz mode of TEM,we have built a magnetic transport test platform for the low-dimensional magnetic materials and single device.The Fe20Ni80 film with thickness of about 30 nm has been prepared by Radio Frequency DC magnetron sputtering.We also Measure the magnetoresistance signal and detect the performance of the instrument. |
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