A Self-Scanned Active-Matrix Tactile Sensor Realized Using Silicon-Migration Technology

A process based on the silicon-migration technology for the monolithic integration of micromechanical devices and complementary metal-oxide-semiconductor (CMOS) circuits is described. A cavity sealed with a silicon cover-diaphragm is first formed without the need of a sacrificial layer etch. The transistors are next fabricated. The issues of material and process incompatibility inherently present in many schemes of microsystem integration are largely avoided using this technique. The technology was demonstrated with the design, fabrication, and characterization of a 16 × 16 active-matrix tactile sensor integrated with a 16-stage CMOS ring counter for row scanning.