An apparatus for semiconductor processing capable of performing semiconductor processing such as etching, depositing, etc. on a surface of a substrate such as a wafer. The apparatus for semiconductor processing, comprises: a reaction chamber having a gate through which a substrate to be processed is transferred; one or more shower heads disposed at an upper side of the reaction chamber, for spraying gas so as to perform semiconductor processing; one or more wafer supporting units disposed at an inner lower side of the reaction chamber in correspondence to each of the shower heads, for supporting the substrate; a processing space forming unit disposed in the reaction chamber, for forming a processing space for semiconductor processing by sealing the shower heads and the wafer supporting units; and an exhausting system connected to the processing space forming unit for controlling a pressure and air exhaustion inside the reaction chamber and the processing space formed by the processing space forming unit.