Patent ID: 8493171

Claim:
A method of forming a trimmable resistance structure in an integrated circuit die, the method comprising: forming a first and a second metal interconnection structure spaced from each other and overlying a semiconductor substrate having transistors formed therein; forming a thin film resistive structure overlying the first and second metal interconnection structures and extending from the first metal interconnection structure to the second metal interconnection structure and being positioned over the semiconductor substrate, the resistive structure being composed of a material whose resistance is permanently changeable by application of heat thereto; forming a dielectric layer over the resistive structure; forming a heater overlying the dielectric layer, the dielectric layer being positioned between the heater layer and the resistive structure, the resistive structure being positioned between the heater and semiconductor substrate; and forming a switch in the semiconductor substrate configured to selectively couple the heater to a voltage supply to cause the heater to heat the resistive structure to cause a permanent change in the resistance of the resistive structure.