COMPOSITE MEMS FLOW SENSOR ON SILICON-ON-INSULATOR DEVICE AND METHOD OF MAKING THE SAME

摘要

The present invention disclosed a micromachined composite silicon flow sensor that is comprised of calorimetric and anemometric flow sensing elements, time-of-flight sensing elements as well as independent temperature sensing elements on a silicon-on-insulator device where the device layer is used for the thermal isolation membrane. The disclosed composite silicon flow sensor can measure mass flowrate, volumetric flowrate and flow medium temperature simultaneously, from which a full spectrum of flow parameters including flow pressure can be obtained. The sensor can be further used to alert any changes in physical properties of flow medium during operation. The disclosed manufacture process details the micromachining process of making such a sensor.

主权项

1. A MEMS silicon composite flow sensor made on a silicon-on-insulator device that is comprised of:
A MEMS silicon composite flow sensor made on a silicon-on-insulator device having calorimetric and anemometric sensing elements, time-of-flight sensing elements and an independent environmental temperature sensor, which include a micro-heater thermistor placed at the center of the sensing elements; wherein said MEMS silicon composite flow sensor having through-holes on silicon substrate that are filled with conductive materials and electrically connected to the thermistors on the front surface; and wherein said silicon-on-insulator having its device layer as the membrane supporting the sensing thermistors of the said composite flow sensor; wherein said MEMS silicon composite flow sensor having a thermal isolating cavity beneath the micro-heater and sensing thermistors; wherein said MEMS silicon composite flow sensor having surface passivation layer with the highly thermal conductive materials; wherein said MEMS silicon mass flow sensor having the backside contacts connecting to the conductive through substrate materials and is ready for package with die-attachment equipment.