Substrate treatment apparatus and substrate treatment method

A substrate treatment apparatus comprising:

• a substrate holding unit which horizontally holds a substrate;
• a substrate rotating unit which rotates the substrate held by the substrate holding unit about a vertical axis;
• a treatment liquid pipe having an outlet port to be opposed to a lower surface of the substrate held by the substrate holding unit, the treatment liquid pipe extending downward from the outlet port along the vertical axis and having an inside space through which a treatment liquid flows to be supplied to the outlet port;
• an opposing member fixed to an upper end of the treatment liquid pipe to be opposed to the lower surface of the substrate held by the substrate holding unit;
• and
• a pipe elongating mechanism which elongates the treatment liquid pipe by a pressure of the treatment liquid to cause the treatment liquid pipe to have a greater pipe length when the treatment liquid flows through the treatment liquid pipe than when the treatment liquid does not flow through the treatment liquid pipe.

A substrate treatment method comprising:

• a substrate holding and rotating step of horizontally holding and rotating a substrate;
• a treatment liquid supplying step of supplying a treatment liquid to an upper surface of the substrate;
• and
• an opposing member placing step of placing an opposing member in opposed spaced relation to the upper surface of the substrate so that the opposing member can receive a lift force from a film of the treatment liquid formed on the upper surface of the substrate in contact with the treatment liquid film, the opposing member being held by a support member in a vertically relatively movable manner.