Abstract: Provided are carrier heads that include a carrier body; and a retainer ring coupled to the carrier body. A weight adjusting groove recessed into the retainer ring by a predetermined depth is disposed at an upper surface of the retainer ring.

Abstract: The present disclosure relates to a retainer ring for a chemical mechanical polishing apparatus and a chemical mechanical polishing apparatus including the same, and the retainer ring of a head portion in a chemical mechanical polishing apparatus includes: an inner ring configured to surround a circumference edge of a wafer; an outer ring surrounding the inner ring; and a fluid flow path formed between the inner ring and the outer ring, the fluid flow path defined by an outward-facing surface of the inner ring and an inward-facing surface of the outer ring. The inward-facing surface of the outer ring includes at least one lower curved portion.

Abstract: Embodiments provide an organic compound, an organic ligand, an optoelectronic device including the organic compound or the organic ligand, an electronic apparatus including the optoelectronic device, an electronic equipment including the electronic apparatus, and an organic semiconductor thin film including the organic compound or the organic ligand.