Apparatus for etching semiconductors

Apparatus for etching of semiconductors, comprising: an electrostatic chuck within a processing chamber, wherein a peripheral region of a top portion of the electrostatic chuck is recessed by a fixed distance down to a fixed depth to form a stepped annular mounting portion; a border ring member having an outer member and an inner member in a body, wherein the outer portion has a thickness which is greater than a height of a vertical surface of the annular mounting portion of the electrostatic chuck, and wherein the inner part from an inner diameter surface of the outer part protruding inwardly to be positioned close to the vertical surface of the annular mounting portion, wherein an upper surface and a lower surface of the inner part in each case to an equal amount of upper and lower inner diameter surfaces of the outer part up and down are stepped; and a spacer member having an annular shape and is arranged on a horizontal surface of the annular mounting portion of the electrostatic chuck, wherein ...