Selective tungsten removal
AssigneeApplied Materials, Inc.
InventorsXikun Wang, Nitin Ingle
Life of this patent
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Abstract
Exemplary methods for removing tungsten-containing material may include flowing a chlorine-containing precursor into a processing region of a semiconductor processing chamber. The methods may also include flowing methane into the processing region of the semiconductor processing chamber. The methods may include forming a plasma from the chlorine-containing precursor and the methane to produce plasma effluents. The methods may also include contacting a substrate with the plasma effluents. The substrate may include an exposed region of a tungsten-containing material. The plasma effluents may produce an oxychloride of tungsten. The methods may also include recessing the exposed region of the tungsten-containing material.
Claims19
An etching method comprising:
- flowing a chlorine-containing precursor into a processing region of a semiconductor processing chamber;
- flowing methane into the processing region of the semiconductor processing chamber;
- forming a plasma from the chlorine-containing precursor and the methane to produce plasma effluents;
- contacting a substrate with the plasma effluents, wherein the substrate comprises an exposed region of a tungsten-containing material, and wherein the plasma effluents produce an oxychloride of tungsten;
- and
- recessing the exposed region of the tungsten-containing material.
An etching method comprising:
- flowing a chlorine-containing precursor into a processing region of a semiconductor processing chamber;
- flowing a hydrocarbon precursor into the processing region of the semiconductor processing chamber;
- forming a plasma from the chlorine-containing precursor and the hydrocarbon precursor to produce plasma effluents;
- contacting a substrate with the plasma effluents, wherein the substrate comprises a first region of a tungsten-containing material and a second region of a first silicon-containing material, and wherein the substrate further comprises a metal nitride liner interposed between a third region of the tungsten-containing material and a fourth region of a second silicon-containing material;
- selectively etching the first region of the tungsten-containing material relative to the second region of the first silicon-containing material;
- and
- selectively etching the metal nitride liner relative to the first and the second silicon-containing material.
An etching method comprising:
- flowing diatomic chlorine at less than or about 250 sccm into a processing region of a semiconductor processing chamber;
- flowing methane at less than or about 50 sccm into the processing region of the semiconductor processing chamber;
- forming a plasma from the diatomic chlorine and the methane at a plasma power of between about 10 W and about 250 W to produce plasma effluents;
- contacting a substrate with the plasma effluents, wherein the substrate comprises an exposed region of a tungsten-containing material and an exposed region of a silicon-containing material;
- etching the exposed region of the tungsten-containing material at a rate of at least about 400 Å per minute, wherein the etching method has a selectivity of the tungsten-containing material to the silicon-containing material greater than 100:1;
- wherein a temperature of the substrate is maintained at about 250° C. during the etching of the exposed region of the tungsten-containing material;
- and
- wherein a pressure of the semiconductor processing chamber is maintained at or below about 10 Torr during the etching of the exposed region of the tungsten-containing material.
Dependencies are inferred from the claim text.