Etching solution for selectively removing tantalum nitride over titanium nitride during manufacture of a semiconductor device
AssigneeVersum Materials US, LLC
InventorsWen Dar Liu, Yi-Chia Lee
Life of this patent
Estimating the term…
Abstract
Described herein is an etching solution comprising water; phosphoric acid solution (aqueous); a fluoride ion source; and a water-miscible organic solvent. Such compositions are useful for the selective removal of tantalum nitride over titanium nitride from a microelectronic device having such material(s) thereon during its manufacture.
Claims22
An etching composition suitable for the selective removal of tantalum nitride over titanium nitride from a microelectronic device, which comprises:
- from about 40% to about 80% by weight water;
- from about 10% to about 50% by weight phosphorous-containing inorganic acid or salt thereof (neat);
- from about 0.1% to about 6% by weight fluoride ion source (neat);
- and
- from about 12% to about 35% by weight water-miscible organic solvent, wherein said etching solution is substantially free of oxidizing agents.
A method of selectively enhancing the etch rate of tantalum nitride relative to titanium nitride on a microelectronic device comprising tantalum nitride and titanium nitride, the method comprising the steps of:
- contacting the microelectronic device comprising tantalum nitride and titanium nitride with an etching composition comprising from about 40% to about 80% by weight water;
- from about 10% to about 50% by weight phosphorous-containing inorganic acid or salt thereof (neat);
- from about 0.1% to about 6% by weight fluoride ion source (neat);
- and from about 12% to about 35% by weight water-miscible organic solvent;
- wherein said etching solution is substantially free of oxidizing agents;
- and
- rinsing the microelectronic device after the tantalum nitride is at least partially removed, wherein the selectivity of the etch for tantalum nitride over titanium nitride is greater than 3.
Dependencies are inferred from the claim text.