Thermoresistance sensor structure for integrated circuits and method of making

摘要

A first pair of resistors formed in a first layer of material, and a second pair of resistors formed in the first layer or in a second layer can be wired into a Wheatstone bridge to form a temperature sensor. Either layer can include a semiconductor or a dielectric. In a semiconductor layer, a pair of resistors can be doped areas of the layer, while in a dielectric, a pair of resistors can be material deposited in cavities in the layer, such as material from an added “middle-of-line” (MOL) metallization layer.

主权项

1. A thermoresistance sensor structure for an integrated circuit comprising:
a first layer of material of an integrated circuit; first and second front-end-of-line (FEOL) resistors made from a first resistor material including a first material of the first layer, the first resistor material having a first thermal coefficient of resistance (TCR), the first and second resistors having respective first and second resistance values at a reference temperature; third and fourth resistors made from a second resistor material including one of the first material of the first layer or a second material of a second layer of the integrated circuit, the second resistor material having a second TCR that differs from the first TCR by a predetermined TCR difference, the third and fourth resistors having respective second and fourth resistance values at the reference temperature; and metal wires from a 1× back-end-of-line (BEOL) metallization (Mn) layer of the integrated circuit that form a Wheatstone bridge by connecting the first FEOL resistor and the fourth resistor in series as part of a first leg of the Wheatstone bridge, and connecting the second FEOL resistor and the third resistor in series as part of a second leg of the Wheatstone bridge, wherein the first and second FEOL resistors are opposed relative to each other within the Wheatstone bridge, the third and fourth resistors are opposed relative to each other within the Wheatstone bridge, an output voltage of the Wheatstone bridge is a predefined value at the reference temperature, and the output voltage is indicative of a difference in temperature between a current temperature of the bridge and the reference temperature according to a predefined relationship between at least the first TCR, the second TCR, the first, second, third, and fourth resistance values, and the difference in temperature.