Design And Research Of Nano-structured Surface Microcantilever Sensor

Microcantilever biosensors are one of the most promising platforms for the next generation of labelless biosensing applications,transforming biometric events into mechanical movements ranging from a few nanometers to hundreds of nanometers.According to the detection method of sensor signal,it can be divided into dynamic and static,among which the static detection has higher stability in the solution environment and is widely used.Microcantilever biosensor is very sensitive to detect small mass changes.However,as most of the commonly used microcantilever structures are flat and smooth surfaces,the number of adsorption sites of the measured object is limited.Therefore,the microcantilever structure with smooth surface is an important factor affecting the sensitivity of the sensor.In view of this situation,in this paper,the collection surface of the microcantilever beam was roughened or nano-sized structure was added to obtain higher detection sensitivity.In this paper,the detection principle,development process and application of microcantilever beam sensor are introduced,and then the method of how to increase the sensor sensitivity is summarized.Finally,the photolithography technology based on metaldielectric-metal(MIM)type periodic hole array structure to excite plasma was selected to realize the preparation of nano-structures on the micro-cantilever beam,so as to increase the adsorption area.Firstly,the plasma lithography system was built.Then,the preparation method of MIM film structure and the technology of preparing dielectric layer by anodic oxidation method were carefully introduced and explained.The mature and well-tuned alumina film is used as the dielectric layer of MIM thin film structure.The whole MIM thin film structure can be prepared by sputtering gold layer on both sides of the dielectric layer.Finally,the prepared MIM film was put into the established lithography system,and a laser was used to apply a certain amount of energy to its surface,so as to carry out experimental analysis of plasma ablative materials.During the experiment,the holes on the surface of the micro-cantilever beam can be etched and gold particles can be added by adjusting the laser energy.After the completion of the hole etching on the surface of the micro-cantilever beam or the addition of gold particle structure,this paper also based on the detection principle of the optical lever method reading way,the experimental platform of the micro-cantilever beam sensor was designed to make sufficient preparation for the subsequent further construction.