Method of depositing low dielectric constant silicon carbide layers

A method of fabricating a metal interconnect structure, comprising:

• providing a substrate having a metal layer thereon;
• forming a nitrogen-containing silicon carbide barrier layer on the metal layer, wherein the nitrogen-containing silicon carbide barrier layer is formed by reacting a gas mixture comprising a silicon source, a carbon source, and a nitrogen source in the presence of an electric field;
• forming a silicon carbide cap layer on the nitrogen-containing silicon carbide barrier layer;
• forming a first dielectric layer on the nitrogen-containing silicon carbide barrier layer;
• forming a nitrogen-containing silicon carbide hard mask on the first dielectric layer, wherein the nitrogen-containing silicon carbide hard mask is formed by reacting a silicon source, a carbon source, and a nitrogen source in the presence of an electric field;
• patterning the nitrogen-containing silicon carbide hard mask to define vias therethrough;
• forming a second dielectric layer on the patterned nitrogen-containing silicon carbide hard mask;
• patterning the second dielectric layer to define interconnects therethrough, wherein the interconnects are positioned over the vias defined in the nitrogen-containing silicon carbide hard mask;
• transferring the via pattern through the first dielectric layer using the nitrogen-containing silicon carbide hard mask as a mask;
• and
• filling the vias and interconnects with a conductive material.

A method of thin film deposition, comprising:

• positioning a substrate in a deposition chamber;
• providing a gas mixture to the deposition chamber, wherein the gas mixture comprises a silicon source, a carbon source, and a nitrogen source;
• reacting the gas mixture in the presence of an electric field to form a nitrogen-containing silicon carbide layer on the substrate;
• forming a silicon carbide cap layer on the nitrogen-containing silicon carbide layer;
• defining a pattern in at least one region of the nitrogen-containing silicon carbide layer and silicon carbide cap layer by a method comprising:
• forming an intermediate layer on the silicon carbide cap layer;
• forming a layer of energy sensitive resist material on the intermediate layer;
• introducing an image of the pattern into the layer of energy sensitive resist material by exposing the energy sensitive resist material to patterned radiation;
• developing the image of the pattern introduced into the layer of energy sensitive resist material;
• and
• transferring the image of the pattern developed in the layer of energy sensitive resist material through the intermediate layer using the layer of energy sensitive resist material as a mask;
• and
• transferring the pattern through the nitrogen-containing silicon carbide layer and silicon carbide cap layer using the intermediate layer as a mask;
• and
• transferring the pattern defined in the at least one region of the nitrogen-containing silicon carbide layer and silicon carbide cap layer into the substrate using the nitrogen-containing silicon carbide layer and silicon carbide cap layer as a mask.