Research On Sapphire Self-organizing Nanostructures Eroded By Low Energy Ion Beam

Sapphire crystal has stable chemical properties, and it is able to withstand high temperature and it has high wear resistance, high hardness and mechanical strength. It has wide transmission band, which covers the UV, visible, infrared and the microwave band.It is widely applied in many areas, such as high-temperature and high-pressure devices, optical system, special window, wear devices, infrared guidance, missile radome, military, civil, scientific research, and other high-tech fields. However, sapphire is a kind of the high hardness oxide, it is difficulty in etching because its hardness is second to diamond, the Mohs hardness is 9.3. The available processing methods are difficulty to meet the manufactural demands of sapphire. As a new type of optical manufactural technology, the low-energy ion beam entching technology has many advantages to satisfy the requirement of the sapphire components processing, such as good directivity, high resolution, flexible processing and good repeatability. Therefore the ion beam etching prepapation of nano-structure of sapphire is researched in this paper.ECR was employed to etch the surface of sapphire, etching effects of low energy Ar ion beams with different ion energies, fluxes, angle, action time and sample rotating under ion incidence were studied. Combined with low energy ion beam etching technology theoretical, the effects of different ion beam parameters on the etched sapphire surface morphology, the height of the nano structure and roughness are analyzed.The experiment results indicate that as following:1 During the preparation of sapphire surface nanostructure not rotating the influence factors of the experiment.The stripy nano structures are obtained by using the method of single factor experiment. The study found that when the sapphire sample etch without rotation, under the angle from 55°to 75°, energy from 1400eV to 1800eV, ion flux from 35mA to 50mA, action time from 30min to 90min, the stripy nano-structure is availabled. The height of the nano-structure is improved as the energies and fluxes increased. And its order is improved as the etching time increasd.2 During the preparation of sapphire surface nanostructure rotating the influence factors of the experiment. The dot nano structures are obtained by using the method of single factor experiment. The study found that when the sapphire sample case with rotation, under the angle from 55°to 70°, eneger from 1400eV to 1800eV, ion flux from 35mA to 55mA, action time from 30min to 90min, the dot nano-structure is availabled. The height of the nano-structure is improved as the energies and fluxes. And its order is improved as the etching time increasd.3 When the sapphire sample etch without rotation, the influence of various factors on the sapphire surface structure is obtained which is the angle> ion flux> energy> action time. through the four factors three levels orthogonal experiment. And the best formula of low energy ion beam etching sapphire sample experiment is that the angle is 69°, ion flux is 55mA, the energy is 1800eV and the action time is 120min. Then we do an experiment with the best parameters,and there are ribbon pattern nano structures appear on the surfaces of the sample.