Computer Simulation For Photonic Microstructures Produced By Multi-beam Interference

Computer simulation can provide new and high efficient method for science and technologyresearch. By simulation, we can do some real experiments on the objects under studying, just likeby physical and chemical methods, and can analyze the expected characteristics of those objectsaccording the simulated data. Due to the rapid calculate speed of computer, lots of simulationexperiments can be carried out during very short time, which can save more time and costcompared with the actual experiments. For the convenience of computer simulation, it has beenwidely used in many fields of science and technology.Since the concept of photonic crystal was put forward by scientist in the late of1980s,microfabrication technologies have become the research hotspot in the international scope. As anefficient and fast method for preparing photonic crystals, holographic lithography has attractedmore and more attentions of researchers in the worldwide. Due to involve multi-beam interference,optical parameters will have a major impact on the preparation of the micro structures inholographic lithography. By calculating optical field of multi-beam interference, the influence ofoptical parameters on the photonic structures can be simulated, and the results of computersimulation can give clear guidance on the actual experiment preparation, which will greatly reducethe time and cost of holographic lithography. In addition, the innovative photonic structures withmore unique properties can be expected by simulating new-type beam configurations. So thecomputer simulation of holographic lithography has very important guiding significance to thepreparation of photonic crystal structure. Based on the theory of multi-beam interference, theinfluence of polarizations and intensities on the structures were discussed by computer simulationin this paper.The main works of this thesis can be summarized as follows:1. The theory of holographic interference was analyzed, and the software used in simulation andthe simulation method were introduced. Besides, optical parameters which have greatly influenceon structures were analyzed.2. Based on the theory of holographic lithography, one dimensional interference structure wasstudied firstly. The influence of polarization states and intensity non-uniformity of two linearpolarized beams on the pattern contrast were simulated. Besides, the changes of the width of theinterference fringes were analyzed with different polarization and intensity.3. For the two-dimensional lattice structure, three linear polarized beams configuration and fourlinear polarized beams configuration were simulated respectively. The results show that thenon-uniformity of light intensity will generate different structures. 4. Three dimensional chiral spiral structure was achieved by using five beams configuration.With four linear polarized beams and one circular polarized beam, we simulated the distribution ofinterference field and got the spiral structure. The effects of incident angle, phase and polarizationof linear polarized beams on interference structures were analyzed respectively.