Patent References 3766616 Microresonator packaging and tuning Semiconductor integrated circuit for a timepiece Coupled mode tuning fork type quartz crystal vibrator Electronic timepiece Linearizer circuit and an electronic watch incorporating same Semiconductor acceleration sensor and vehicle control system using the same Admittance-parameter estimator for a piezoelectric resonator in an oscillator circuit Micromachined thermal switch System and method for diagnosing characteristics of acceleration sensor InventorsAssigneeApplicationNo. 957802 filed on 10/24/1997US Classes:257/415, Physical deformation257/467, Temperature374/187Mechanical (e.g., expansion or contraction of materials)ExaminersPrimary: Chaudhuri, OlikAssistant: Wille, Douglas A. Attorney, Agent or FirmInternational ClassH01L 029/82AbstractAn integrated circuit and method are provided for sensing activity such as temperature variations in a surrounding environment. The integrated released beam sensor preferably includes a switch detecting circuit region and a sensor switching region connected to the switch detecting circuit region. The sensor switching region preferably includes a fixed contact layer, a sacrificial layer on the fixed contact layer, and a floating contact on the sacrificial layer and having portions thereof overlying the fixed contact layer in spaced relation therefrom in an open switch position and extending lengthwise generally transverse to a predetermined direction. The floating contact preferably includes at least two layers of material. Each of the at least two layers have a different thermal expansion coefficient so that the floating contact displaces in the predetermined direction responsive to a predetermined temperature variation so as to contact the fixed contact layer and thereby form a closed switch position. The methods of forming an integrated sensor advantageously are preferably compatible with known integrated circuit manufacturing processes, such as for CMOS circuit manufacturing, with only slight variations therefrom. | |