P2E-2 Study of Particles Separation in the Ultrasonic Microdevice

In this paper, a new MEMS device that can separate microparticles on-chip by the use of bulk-mode excited membrane vibration is proposed, designed and microfabricated. By starting from the one-dimensional analytical mode of forces acting on particles,the force for ultrasonically separating particles is profoundly studied, and finite element method in ANSYS is used to analyze the vibration modes, the acoustic field and flow field in the microdevice due to the membrane vibration. With these analyses, we obtain the ultrasonic radiation force acting on different kinds of particles in the water, blood plasma and milk medium when the microdevice vibrates at different frequencies and then study their separation.