Plasma etching chamber and method for manufacturing photomask using the same

A plasma etching chamber comprising:

• an electrode including
• a supporting surface for supporting a photomask substrate, and
• a top surface surrounding the supporting surface;
• a chucking pad arranged below the electrode, the chucking pad having a contact surface in contact with corner portions of the photomask substrate for fixing the photomask substrate supported by the supporting surface;
• a heat transfer element installed within the chucking pad to heat the corner portions of the photomask substrate;
• and
• a heater for supplying heat to the heat transfer element.

A method for manufacturing a photomask comprising:

• forming a shading layer on a transparent substrate;
• forming a photoresist layer pattern on the shading layer so as to partially expose the shading layer;
• etching the shading layer using plasma to form a shading layer pattern, and using the photoresist layer pattern as an etching mask;
• and
• heating the transparent substrate, while etching, such that a temperature of at least one portion of a peripheral edge of the transparent substrate is maintained higher than a temperature of a center portion of the transparent substrate.