Polishing head, wafer polishing apparatus using the same, and wafer polishing method using the same

A polishing head of a wafer polishing apparatus for polishing one side of a wafer, comprising:

• a membrane head capable of independently controlling a center control pressure for pressing the center portion of a wafer and an outer periphery control pressure for pressing the outer peripheral portion of the wafer;
• an outer ring integrally formed with the membrane head so as to constitute the outer peripheral portion of the membrane head;
• and
• a contact type retainer ring provided outside the membrane head, wherein
• the membrane head has:
• a single compartment central pressure chamber configured to control the center control pressure;
• and
• an outer peripheral pressure chamber provided above the central pressure chamber and configured to control the outer periphery control pressure,
• a position of a lower end of the outer ring reaches at least a position of an inner bottom surface of the central pressure chamber, and
• a position of an upper end of the outer ring reaches at least a position of an inner upper surface of the central pressure chamber.