Research Of The Surface Wrinkling On Micro-structures

Surface wrinkling covering on soft materials are of growing interest to a numberof academic disciplines including soft lithography, metrology and flexible electronics.In this paper, to study how to control the morphology of the surface wrinkles,experiments and simulations have been done. There are three main aspects:controlling of the morphology of the surface wrinkling and the finite element analysis(FEA) of the wrinkle of thin film, fabrication of the micro-grooving structures and itsFEA simulation, eliminating the ringing artefacts of the carbon nanotube probes ofatomic force microscopy (AFM CNT probe) when detecting steep samples.By thermal deposition method, surface wrinkles on soft material were achieved.During successful experiments, grating-like wrinkles and zigzag wrinkles weresuccessfully obtained. By observing the morphology of the wrinkles, it was foundwrinkles around the circle structure and the direction of the circumference aremutually orthogonal; when near the groove structure, it was also found wrinkles andthe edge of groove are perpendicular, and the wrinkles in the groove have a very goodcycle stability and direction consistency. These results also illustrate that the wrinklesmade by thermal deposition on the surface with characteristic structure are alwaysperpendicular with the edge of the structure.Then the wrinkles of thin film wereanalysis by us by using buckling method. The wrinkle morphology of stretched filmwas simulated by nonlinear buckling method, and a method to calculate the surfacewrinkle was put forward by us.By using the FEA software DEFORM, cutting progress was simulated indifferent cutting speed and different kinds of V-shaped micro-cutters. From severalaspects, the burrs of different cutting parametersweresimulated;it was found that theincrease of rake angle will get better surface quality. At last, the simulation resultswere compared with the experiment results.When the AFM CNT probes detect steep samples, ringing artefacts often easilyoccurred.This paper discussed the ringing artefacts ofcarbon nanotube probe focusedon how to capture the true sample morphology derivingfrom the ringing artefacts bymathematical model and experiment result. The scandirection was found to have aprominent influence on the artefacts’ consistency andcycle, and the distance of the gaps between the lowest points of the artefacts and thetrench obeys a certain rule. Byestablishing mathematical model, formulae were givento calculate the gaps. Finally,the theoretic morphology can be acquired, and it is ingood agreement with theno-artefact images.