Micromachined Piezoresistive Tactile Sensor Array Fabricated by Bulk-etched MUMPs Process

摘要

The design, fabrication and testing of a 5x5 micromachined tactile sensor array for the detection of an extremely small force (micrometer-Newton range) has been discussed. An anisotropic etching of silicon substrate of a MUMPs process chip forms a central contacting pads that are trampoline-shape suspended structures and sensor beams. A piezoresistive layer of polysilicon embedded in sensor beams is used to detect the displacement of the suspended contacting pad. Each square tactile has dimension of 200 μm x 200 μm with 250 μm center-to-center spacing. The entire sensor area is 1.25 mm x 1.25 mm. The device was tested characterized under various normal force loads using weight microneedles. The individual sensor element shows the linear response to normal force with good repeatability.