Study On Fabrication And Optical Properties Of The Microstructures Based On The Femtosecond Laser Two-photon

In recent years,owing to the development of electronic technology and the micro and nano fabrication technology,miniaturization and integration of various devices have become a trend.The microstructure has been widely used in the fields of aerospace engineering,biomedical,mechanical industry and national defense.There are many ways to fabricate the microstructure,but femtosecond laser two photons micro-fabrication has become a hot topic for its advantage of high accuracy,small thermal effect,without covering film,high flexibility and the realization of the three dimensional fabrication.Two photons absorption is the process of the atom absorbing the energy of two photons and translating to the excited state.Focusing on a small valume,two photons polymerization can fabricate the microstructure beyond the limitation of the diffraction.The main research results are as follows:1.A 3×3 micro hexagonal pyramid array is fabricated based on the technology of femtosecond two photons by using the photoresist which is doped with the Rhodamine 6G.When the sample is irradiated by the 532 nm green laser,compared with the sample without Rhodamine 6G,an emission peak is found around the wavelength of 550 nm.The diffraction of the sample is measured,and the difference of the period between the prediction from the diffraction of the sample and designed value is 2.3%.2.A two dimensional metal grating is fabricated based on lift-off technique.A measuring device is designed to detect the two dimensional incident angle and the wavelength of the laser.The device consists of a fabricated 2D metal grating,a transparent screen and a camera.And its detecting reliability is tested under the laboratory condition.The results show that the measured two dimensional angles are scatter around the ideal line and the deviation about detecting the wavelength in both X,and Y direction are smaller than 10 nm,which proves the reliability of the device.3.Complementary L shape chiral metal array is fabricated on the infrared glass substrate,and the period of the structure is 8 ?m.The fabrication of the L shape chiral metal array is beneficial for the fabrication and characteristic research on the infrared chiral structure.4.A device of observing three dimensional structure under the microscope is invented.This device consists of a rotatable unit and three moving stages which are overlapped in sequence and can move in the direction of X,Y and Z respectively.The rotatable unit has an axis of rotation which can rotate 360 degree.The sample is tied to the outer side of the axis so that it can be rotated 360 degree on this device,which makes it possible to observe the shape and the size of the microstructure omnibearingly.Compared with the scanning electron microscope(SEM),the device is easier to operate and less expensive.5.A device and a method of measuring the similarity between two microstructures are invented.The device consists of the microscope,computer,Raspberry Pi data processing module and the display module.Compared with the existing technology,the advantages of the device are that it can estimate the quality and find the problem of the structure through measuring the similarity between two microstructures under the repeating fabrication.