Gas supply unit and thin film deposition apparatus including the same

A thin film deposition apparatus, comprising:

• a body with an accommodating groove therein;
• a rotatable susceptor in the accommodating groove, the susceptor supporting a plurality of substrates;
• and
• a gas supply unit coupled to an upper portion of the body, the gas supply unit facing the susceptor to inject a plurality of gases toward the susceptor,
• wherein the gas supply unit includes:
• a base plate,
• a plurality of gas supply regions protruding from the base plate, the plurality of gas supply regions being arranged on the base plate in a circumferential direction, and
• a plurality of sidewall trenches defined by facing sidewalls of adjacent gas supply regions of the plurality of gas supply regions,
• wherein each of the plurality of sidewall trenches has a depth that decreases in a radial direction from a center of the base plate.

A gas supply unit, comprising:

• a base plate;
• a plurality of gas supply regions protruding from the base plate, the plurality of gas supply regions being arranged on the base plate in a circumferential direction;
• and
• a plurality of sidewall trenches on the base plate, the plurality of sidewall trenches and the plurality of gas supply regions being alternately arranged along the circumferential direction of the base plate,
• wherein each of the plurality of sidewall trenches has a decreasing depth in a radial direction from a center of the base plate toward an edge of the base plate.