Microfluidic dynamic system for biological fluids viscosity measurements

The purpose of this research was to model, design and fabricate a microdynamic system, using a four masks silicon micromachining process and sacrificial layers technique. The measurement principle is the detection of the rotation of a micromachining polysilicon gear wheels system with external diameters of 250 /spl mu/m, 200 /spl mu/m, 160 /spl mu/m and 3 /spl mu/m thickness combine the undercut and refill technique with pin-joint bearing permitting the fabrication of bushings that can be used, for example, to elevate the rotor away from the silicon surface. The microfluidic dynamic system consists of a gear wheels system, an electromagnetic micropump and a magnetic controller. Each device is fabricated by silicon micromachining technology and tested to obtain the specific characteristics.