A dry etching method and apparatus improves the uniformity of etching a wafer in the manufacture of a semiconductor device. The dry etching apparatus has a susceptor supporting the wafer, a cooling system installed in the susceptor, an upper RF (radio frequency) electrode which may incorporate a gas diffuser for spraying reactive gas toward the wafer, and an RF power source for producing an electric field used to react the gas and generate plasma. The gap between the upper RF electrode and the susceptor is configured to accommodate for distortions in the wafer or other processing requirements. In addition, the nozzles of the gas diffuser can be configured to spray different amounts of gas to also enhance the etching uniformity. Finally, one of the electrodes may be divided into concentric sections. In this case, the RF power source can generate electric fields of different intensities at the sections. When the divided electrode is the susceptor, the cooling system cools the sections to different temperatures to in turn temperature-condition the wafer in a manner determined in advance to enhance the uniformity of the etching process.