A technique for implementing monolithic resistors with near-zero temperature coefficient

A technique for implementing monolithic resistors with near-zero temperature coefficient (NZ-TC) over a wide temperature range is presented. The typical structure of monolithic resistors contains a core resistor that is connected to the circuit interconnects through contacts. Typically, the temperature behaviour of contact resistors is ignored, however, we show that one can take advantage of contact resistors and their temperature dependancy to control/minimize the temperature coefficient (TC) of the overall resistor structure. As a proof of concept several resistor structures have been implemented in a 0.13-μm CMOS technology. The measurement results over the temperature range of 25 to 200°C confirm the validity of the proposed technique. The temperature performance of the implemented resistors is compared with that of conventional resistors. Without loss of generality, the proposed approach can be used to implement a resistor with a given temperature coefficient.