Process for removing titanium nitride layer in an integrated circuit

A process for forming an inter-metal dielectric layer over, and then making electrical contact to, an aluminum layer, within an integrated circuit, which has been previously over and under coated with first and second layers respectively of titanium nitride, comprising:

• depositing a layer of spin-on glass over said integrated circuit;
• etching said layer of spin-on glass for long enough for the first titanium nitride layer to become fully exposed, while still leaving said layer of spin-on-glass in place to prevent any undercutting of said second layer of titanium nitride;
• removing said first layer of titanium nitride;
• coating said integrated circuit with a layer of dielectric material to a thickness sufficient to cover the surface of the integrated circuit;
• etching via holes through said layer of dielectric material wherever electrical contact with said aluminum layer is required;
• forming a conductive layer on said dielectric layer, including the bottoms and sides of said via holes;
• and
• patterning said conductive layer to provide electrical connections to other parts of the integrated circuit.