Method of multiple patterning of a low-K dielectric film

A method of patterning a low-k dielectric film, the method comprising:

• forming and patterning a first mask layer above a low-k dielectric layer, the low-k dielectric layer disposed above a substrate;
• forming and patterning a second mask layer above the first patterned mask layer;
• transferring a pattern of the second patterned mask layer at least partially into the low-k dielectric layer;
• and subsequently,
• transferring a pattern of the first patterned mask layer at least partially into the low-k dielectric layer by first exposing and then modifying portions of the low-k dielectric layer with a first plasma process, and then removing the modified portions of the low-k dielectric layer with a second plasma process having a plasma chemistry different from the first plasma process, wherein the pattern of the first patterned mask layer is transferred into the low-k dielectric layer to a depth less than a depth of the pattern of the second patterned mask layer is transferred into the low-k dielectric layer.

A method of patterning a low-k dielectric film, the method comprising:

• forming and patterning a first mask layer above a low-k dielectric layer, the low-k dielectric layer disposed above a substrate;
• forming and patterning a second mask layer above the first patterned mask layer;
• transferring a pattern of the second patterned mask layer at least partially into the low-k dielectric layer;
• and subsequently,
• transferring a pattern of the first patterned mask layer at least partially into the low-k dielectric layer by first exposing and then modifying portions of the low-k dielectric layer with a first plasma process, and then removing the modified portions of the low-k dielectric layer with a second plasma process having a plasma chemistry different from the first plasma process, wherein transferring the pattern of the first patterned mask layer at least partially into the low-k dielectric layer comprises performing a plurality of process cycles repeating the modifying and removing of portions of the low-k dielectric layer.