Differential temperature sensor and its capacitors in CMOS/BICMOS technology

摘要

The sensor is made on a semiconductor substrate covered with an electrically insulating layer. The electrically insulating layer separates a thermocouple from the substrate. It includes a first portion presenting a first value of capacitance per unit area and a second portion presenting a second value of capacitance per unit area, which is lower than the first value. The sensor includes first and second output terminals connected to the thermocouple. The first output terminal includes a first capacitor having a first electrode formed by a first leg made of an electrically conducting material. The second electrode of the capacitor is formed by a part of the substrate facing said first leg and separated from the first electrode by the first portion of the electrically insulating layer. The first leg connects the thermocouple while overlapping the second portion of the electrically insulating layer.

主权项

1. A thermoelectric device, comprising:
a substrate made from a semiconductor material; an electrically insulating layer covering a first face of the substrate and comprising a first portion presenting a first value of capacitance per unit area and a second portion presenting a second value of capacitance per unit area that is lower than the first value; at least one thermocouple comprising a plurality of legs, the legs being electrically conducting, each of the legs being placed on the electrically insulating layer and separated from the substrate by the electrically insulating layer only, wherein a bottom surface of each of the legs of the at least one thermocouple, a top surface of the first portion of the electrically insulating layer, and a top surface of the second portion of the electrically insulating layer are substantially coplanar, and wherein a first leg of the plurality of legs is made from a first electrically conducting material, the first leg being disposed on the first portion of the electrically insulating layer and overlapping the second portion of the electrically insulating layer; a first output terminal connected to the at least one thermocouple by the first leg, the first output terminal comprising a first capacitor provided with:
a first electrode of the first capacitor formed by the first leg, anda second electrode of the first capacitor formed by a part of the substrate facing the first leg, the first electrode of the first capacitor and the second electrode of the first capacitor being separated from one another by the first portion of the electrically insulating layer.