A thin film resistor (60) is contained between two metal interconnect
layers
(40, 100) of an integrated circuit. Contact may be made to the resistor
(60) through vias (95) from the metal layer (100) above the
resistor (60) to both the thin film resistor (60) and the underlying
metal layer (40) simultaneously. The resistor (60) may include portions
of a hard mask (70) under the vias (95) to protect the resistor material
(60) during the via (95) etch. This design provides increased flexibility
in fabricating the resistor (60) since processes, materials, and chemicals
do not have to satisfy the conditions of both the resistor (60) and the
rest of the integrated circuit (especially the interconnect layer 40) simultaneously.
