One-chip integrated sensor

摘要

A method concurrently forms a micromachine element (54) and an integrated circuit device (12) on the same substrate (18), such that their fabrication requires a minimal number of processing steps. The method can form sensing devices, such as accelerometers (110) and pressure sensors (54) which utilise a small micromachine element, such as a bridge (54), cantilevered beam, suspended mass (60), membrane or capacitive element that is supported over a cavity (22) formed in the silicon substrate (18). Piezoresistors (14) used to detect the deflection of the micromachine element (54, 60) are formed simultaneously with elements of the integrated circuit devices (12), such that a minimal number of processing steps are required.