Research On Micromanipulation Method Based On Capillary Force

With the increasing miniaturization of electronic products,due to the scaling effect,at micro scale,releasing micro objects is problematic and challenging.It is important to study a micromanipulation method that can achieve non-invasive pick-up,transfer and reliable release of micro-objects.This paper proposes a micromanipulation method based on capillary force,which applies a small amount of droplets through a high-precision syringe pump to form a liquid bridge between the operating tool and the micro-object,thereby generating a liquid bridge force to achieve non-invasive picking of the micro-object,and the reliable release of the micro-objects is achieved using double liquid bridge.Firstly,this thesis studies the theoretical basis of capillary force,and proposes a micromanipulation method based on capillary force for picking,transfer and release of micro objects,which studies a small amount of droplets acquisition methods and the release strategies of micro-objects,and divides in detail the micromanipulation process.Furthermore,the thesis investigates the double-iteration algorithm,and a simplified model of the liquid bridge morphology is established for analyses the meniscus shape of the liquid bridge in the process of micromanipulation;The force analysis of micro-objects is carried out according to the physical method for deducing the calculation formula of liquid bridge force,and the change of hydraulic bridge force with contact angle and height is also studied;In addition,the principle of piking and release processes of manipulation is analyzed,which is to study the mechanical conditions to be satisfied in capillary force manipulation.Secondly,a micromanipulation system is designed and set up,including the establishment of three modules: droplet injection module,displacement platform module and visual module.In addition,in order to improve the efficiency and positioning accuracy of the micromanipulation process and avoid the failure of the experiment or the decrease of the operation precision due to the unskilled operation,a control program is developed for rapid picking,transfer and release using lua script language under a software frame called Automation Base.Finally,experiments is carried out based on the established micromanipulation system platform.Firstly,the manufacture of substrate and micro-objects is completed by adjusting and optimizing the parameters of laser marking machine.Then,the volume of droplets and contact angle are calculated using MATLAB for studying the effects of different substrate materials on the droplet volume.Finally,being completed the micromanipulation of picking,transfer and release of the 500?m?500?m and 700?m?700?m micro-objects,and the success rate of micromanipulations are calculated through multiple experiments.At the same time,the feasibility of the micromanipulation method are verified by theoretical calculation.In addition,the picking,transferring and releasing operations of micro-objects with various shapes(triangle,pentagon,hexagon)are also carried out,which further proves that the micromanipulation method can realize flexible picking and is suitable for operation of various shape micro-objects.