Microchip Technology Incorporated
THIN FILM RESISTOR (TFR) FORMED IN AN INTEGRATED CIRCUIT DEVICE USING TFR CAP LAYER(S) AS AN ETCH STOP AND/OR HARDMASK

Abstract:

A method is provided for forming a thin film resistor (TFR) in an integrated circuit (IC) device. A TFR film is formed and annealed over an IC structure including IC elements and IC element contacts. At least one TFR cap layer is formed, and a TFR etch defines a TFR element from the TFR film. A TFR contact etch forms TFR contact openings over the TFR element, and a metal layer is formed over the IC structure and extending into the TFR contact openings to form metal contacts to the IC element contacts and the TFR element. The TFR cap layer(s), e.g., SiN cap and/or oxide cap formed over the TFR film, may (a) provide an etch stop during the TFR contact etch and/or (b) provide a hardmask during the TFR etch, which may eliminate the use of a photomask and thereby eliminate post-etch removal of photomask polymer.