Halogen-free etching of silicon nitride
Methods of semiconductor processing may include providing a hydrogen-containing precursor to a processing region of a semiconductor processing chamber. A substrate may be disposed on a substrate support within the processing region. A layer of silicon-and-nitrogen-containing material may be disposed on the substrate. The methods may include forming plasma effluents of the hydrogen-containing precursor. The methods may include contacting the layer of silicon-and-nitrogen-containing material with plasma effluents of the hydrogen-containing precursor. The contacting may etch a portion of the layer of silicon-and-nitrogen-containing material.
1 . A semiconductor processing method comprising:
providing a hydrogen-containing precursor to a processing region of a semiconductor processing chamber, wherein a substrate is disposed on a substrate support within the processing region, and wherein a layer of silicon-and-nitrogen-containing material is disposed on the substrate;
forming plasma effluents of the hydrogen-containing precursor; and
contacting the layer of silicon-and-nitrogen-containing material with plasma effluents of the hydrogen-containing precursor, wherein the contacting etches a portion of the layer of silicon-and-nitrogen-containing material, wherein the processing region is maintained halogen-free.
2 . The semiconductor processing method of claim 1 , wherein the hydrogen-containing precursor comprises diatomic hydrogen (H 2 ).
3 . The semiconductor processing method of claim 1 , wherein a layer of silicon-and-oxygen-containing material, a layer of silicon-containing material, or both are disposed on the substrate.
4 . The semiconductor processing method of claim 1 , further comprising:
providing an inert precursor with the hydrogen-containing precursor to the processing region.
5 . The semiconductor processing method of claim 4 , wherein a flow rate of the inert precursor is greater than a flow rate of the hydrogen-containing precursor.
6 . The semiconductor processing method of claim 1 , wherein the plasma effluents are formed at a plasma power of greater than or about 800 W.
7 . The semiconductor processing method of claim 1 , wherein the plasma effluents are formed at a plasma power of greater than or about 2,000 W.
8 . The semiconductor processing method of claim 1 , wherein the contacting forms silane (SiH 4 ), ammonia (NH 3 ), or both.
9 . The semiconductor processing method of claim 1 , wherein the substrate is characterized by a temperature of less than or about 50° C.
10 . The semiconductor processing method of claim 1 , wherein the substrate is characterized by a temperature of less than or about −25° C.
11 . The semiconductor processing method of claim 1 , wherein a pressure within the semiconductor processing chamber is maintained at less than or about 100 mTorr.
12 . The semiconductor processing method of claim 1 , wherein the contacting etches the layer of silicon-and-nitrogen-containing material at an etch rate of greater than or about 1 Å/min.
13 . A semiconductor processing method comprising:
providing a hydrogen-containing precursor to a processing region of a semiconductor processing chamber, wherein a substrate is disposed on a substrate support within the processing region, wherein a layer of silicon-and-oxygen-containing material is disposed on the substrate, and wherein a layer of silicon-and-nitrogen-containing material is disposed on the layer of silicon-and-oxygen-containing material;
forming plasma effluents of the hydrogen-containing precursor, wherein the plasma effluents are formed at a plasma power of greater than or about 1,000 W; and
contacting the layer of silicon-and-nitrogen-containing material with plasma effluents of the hydrogen-containing precursor, wherein the contacting selectively etches a portion of the layer of silicon-and-nitrogen-containing material relative to the layer of silicon-and-oxygen-containing material.
14 . The semiconductor processing method of claim 13 , wherein the processing region is maintained halogen-free.
15 . The semiconductor processing method of claim 13 , wherein the substrate is characterized by a temperature of less than or about 50° C.
16 . A semiconductor processing method comprising:
providing a hydrogen-containing precursor to a processing region of a semiconductor processing chamber, wherein a substrate is disposed on a substrate support within the processing region, wherein a layer of silicon-and-oxygen-containing material is disposed on the substrate, and wherein a layer of silicon-and-nitrogen-containing material is disposed on the layer of silicon-and-oxygen-containing material;
forming plasma effluents of the hydrogen-containing precursor; and
contacting the layer of silicon-and-nitrogen-containing material with plasma effluents of the hydrogen-containing precursor, wherein the contacting selectively etches a portion of the layer of silicon-and-nitrogen-containing material relative to the layer of silicon-and-oxygen-containing material, and wherein the substrate is characterized by a temperature of less than or about −50° C.
17 . The semiconductor processing method of claim 16 , further comprising:
providing helium with the hydrogen-containing precursor to the processing region.
18 . The semiconductor processing method of claim 16 , wherein the processing region is maintained halogen-free.
19 . The semiconductor processing method of claim 16 , wherein the plasma effluents are formed at a plasma power of greater than or about 1,000 W.
20 . The semiconductor processing method of claim 16 , wherein the contacting selectively etches the portion of the layer of silicon-and-nitrogen-containing material relative to the layer of silicon-and-oxygen-containing material at a selectivity of greater than or about 5:1.