Patent ID: 8361234

Claim:
A substrate treatment apparatus comprising: a substrate holding unit which holds a substrate; a gas ejection nozzle to be positioned adjacent a center portion of the substrate held by the substrate holding unit, the gas ejection nozzle being configured to eject a gas radially from its gas ejection port over the substrate to form a gas-flow for covering the substrate, the gas ejection nozzle being columnar, the gas ejection nozzle having a smaller diameter than the substrate held by the substrate holding unit, the gas ejection port opening in a side surface of the gas ejection nozzle; a treatment liquid nozzle, the treatment liquid nozzle being partly disposed in the gas ejection nozzle; and a gas supply unit which supplies the gas to the gas ejection nozzle, wherein the gas ejection nozzle includes: a surface opposed to one major surface of the substrate held by the substrate holding unit, said opposed surface being disposed closer to the substrate holding unit than the gas ejection port; a fluid ejection port provided in said opposed surface; and a flow passage connected to the fluid ejection port, the flow passage having an inlet to which a gas is supplied, the inlet having an area being smaller than an area of the fluid ejection port; wherein the gas ejection nozzle further includes a partition portion which partitions the flow passage, the partition portion having a plurality of through-holes penetrating through the partition portion.