a method of and a structure for controlling the temperature of an electrode . the electrode is heated prior to etching the first wafer and both a stationary and a homogeneous temperature of the silicon electrode are maintained . resistive heater elements are either embedded within the housing of the electrode or formed as part of the electrode . the resistive heater elements form a heater of a multi - zone type in order to minimize the temperature non - uniformity . the resistive heater elements are divided into a plurality of zones , wherein the power to each zone can be adjusted individually , allowing the desirable temperature uniformity of the electrode to be achieved . preheating the electrode to the appropriate operating temperature eliminates both the “ first wafer effect ” and non - uniform etching of a semiconductor wafer .