Method and apparatus for controlling air flow in a liquid coater

A method for reducing contaminants from depositing on a wafer surface in a photoresist coating apparatus comprising the steps of:

• providing a coating apparatus comprises an upper compartment and a lower compartment defining a cavity contained therein, said apparatus further comprises at least one adjusting means selected from the group consisting of a bracket means adapted to engage said upper compartment to said lower compartment defining a first height of said cavity and a removable roof member adapted to engage an opening in said upper compartment for defining a second height of said cavity,
• providing a rotatable vacuum chuck for holding a wafer thereon,
• providing a photoresist dispenser for dispensing a predetermined volume of photoresist on a surface of said wafer, and
• adjusting said first height of the cavity by said bracket means or adjusting said second height of the cavity by said removable roof means such that a desirable air flow is generated during a photoresist coating process by said rotating vacuum chuck to prevent the deposition of contaminating particles on said wafer surface.

An apparatus for depositing liquid on a rotating article comprising:

• a coating apparatus having an upper compartment and a lower compartment defining a cavity contained therein,
• a rotatable platform for rotating an article positioned on top,
• a liquid dispensing means suspended over said platform, and
• at least one adjusting means selected from the group consisting of a bracket means adapted for engaging said upper compartment to said lower compartment defining a first height of said cavity and a removable roof member adapted for engaging an opening in said upper compartment defining a second height of said cavity.