Processing gas diffusing and supplying unit and substrate procesisng apparatus

A substrate processing apparatus comprising:

• a processing chamber configured to accommodate a substrate;
• a processing gas diffusing and supplying unit configured to supply a processing gas into the processing chamber;
• and
• a first and a second processing gas introducing pipe configured to introduce the processing gas into the processing gas diffusing and supplying unit,
• wherein the processing gas diffusing and supplying unit includes:
• a main body;
• a plate supported by the main body, the plate having a plurality of gas supply holes for supplying the processing gas into the processing chamber;
• a partition wall;
• an internal space formed in the main body, the internal space having a first and a second space partitioned by the partition wall and the processing gas being supplied through the first and the second processing gas introducing pipe to the internal space;
• a first opening communicating with the first space while facing the plate, the first opening being connected to the first processing gas introducing pipe;
• a second opening communicating with the second space while facing the plate, the second opening being connected to the second processing gas introducing pipe;
• a first shielding portion installed in the first space, the first shielding portion having a surface opposite to the first opening;
• and
• a second shielding portion installed in the second space, the second shielding portion having a surface opposite to the second opening,
• wherein a height of the internal space is equal to or greater than 8 mm so that the processing gas discharged from the first and the second opening is diffused to the first and the second space and is uniformly supplied through the gas supply holes.