Support unit, apparatus for treating substrate with the same

A support unit supporting a substrate at a treating space for plasma treating the substrate, the support unit comprising:

• a dielectric plate having a top surface to place the substrate thereon;
• a top ring surrounding a circumference of the substrate placed on the dielectric plate;
• a temperature sensor measuring a temperature of the top ring;
• a first lifting/lowering member lifting/lowering the top ring;
• a bottom ring surrounding a bottom surface of an edge of the substrate placed on the dielectric plate, the dielectric plate, and an inside of the top ring, and
• a controller controlling the first lifting/lowering member, and
• wherein the bottom ring is combined with the top ring to form an insertion space defining a lifting/lowering limit of the first lifting/lowering member therein, when the top ring is lifted or lowered by the first lifting/lowering member, and
• wherein the controller controls the first lifting/lowering member to change a height of the top ring according to an etching amount of the top ring calculated based on the temperature of the top ring measured at the temperature sensor.

A substrate treating apparatus comprising:

• a housing having a treating space for treating a substrate;
• a support unit supporting the substrate at the treating space;
• a gas supply unit supplying a process gas into the treating space;
• and
• a plasma source generating a plasma from the process gas, and
• wherein the support unit comprises:
• a dielectric plate having a top surface to place the substrate thereon;
• a top ring surrounding a circumference of the substrate placed on the dielectric plate;
• a first lifting/lowering member lifting or lowering the top ring, and
• a bottom ring surrounding a bottom surface of an edge of the substrate placed on the dielectric plate, the dielectric plate, and an inside of the top ring, and
• wherein the bottom ring is combined with the top ring to form an insertion space defining a lifting/lowering limit of the first lifting/lowering member therein, when the top ring is lifted or lowered by the first lifting/lowering member.