Electrostatic chuck and semiconductor manufacturing apparatus

An electrostatic chuck comprising:

• a ceramic dielectric substrate having a first major surface configured to have a process object mounted thereon and a second major surface opposite to the first major surface;
• a base plate supporting the ceramic dielectric substrate;
• and
• a heater unit which heats the ceramic dielectric substrate, wherein
• the heater unit includes a first heater element and a second heater element,
• the second heater element having a plurality of main zones separated from each other in a radial direction,
• the first heater element having a plurality of sub-zones separated from each other,
• a number of the sub-zones being larger than a number of the main zones,
• the main zones including a first main zone,
• the first main zone having a main heater line generating heat by allowing a current to flow and a first main power feeding portion feeding a power to the main heater line,
• the sub-zones including a first sub-zone overlapping the first main zone in a Z-direction perpendicular to the first major surface,
• the first sub-zone having a central region located centrally in the first sub-zone and an outer peripheral region located outside the central region when viewed along the Z-direction, and
• the first main power feeding portion being provided at a position where the first main power feeding portion overlaps the central region in the Z-direction.