A monolithically integrated surface micromachined touch mode capacitive pressure sensor

A monolithically integrated surface micromachined touch mode capacitive pressure sensor and its interface circuits are presented. The device includes the capacitance to voltage, and capacitance to frequency converters on the same chip. The sensor is fabricated using a surface micromachining technology, which is processed simultaneously with a conventional 2.0-mu m double-poly, double-metal n-well CMOS process. The performance of the integrated sensor meets the design specifications of good linearity and good stability. Evaluation results on the completed 'sensor and circuit' chip are presented. (C) 2000 Elsevier Science S.A. All rights reserved.