Enhancement in UV curing efficiency using oxygen-doped purge for ultra low-K dielectric film

A method for processing a substrate, comprising:

• depositing an ultra low-k dielectric layer having a dielecric constant of less than about 2.5 on a substrate in a deposition chamber;
• transferring the substrate to an ultraviolet (UV) processing chamber;
• flowing an oxygen gas and a purge gas comprising helium gas and argon gas into the UV processing chamber at a flow ratio of about 1 (oxygen gas):
• 6400 (purge gas) to about 1 (oxygen gas):300 (purge gas), wherein the oxygen gas is flowed into the UV processing chamber at a flow rate of about 1.0 sccm to about 30 sccm for a 300 mm diameter substrate;
• exposing the deposited ultra low-k dielectric layer to UV radiation;
• turning off UV radiation or remains on;
• terminating flow of the oxygen gas while still flowing helium gas and argon gas into the UV processing chamber;
• and
• pumping residues and unwanted produces out of the UV processing chamber.

A method for processing a substrate, comprising:

• subjecting an ultra low-k dielectric layer having a dielecric constant of less than about 2.5 to a ultraviolet (UV) curing process in a UV processing chamber, comprising:
• flowing a purge gas and an oxygen gas into the UV processing chamber at a flow ratio of about 1 (oxygen gas):6400 (purge gas) to about 1 (oxygen gas):300 (purge gas), wherein the oxygen gas is flowed into the UV processing chamber at a flow rate of about 1.0 sccm to about 30 sccm for a 300 mm diameter substrate;
• and
• exposing the ultra low-k dielectric layer to UV radiation.