Shower plate

Patent Granted To provide a shower plate which can prevent generation of backflow of plasma or firing of plasma excitation gas at a longitudinal hole more perfectly, and can ensure efficient plasma excitation. In a shower plate 105 arranged in the processing chamber 102 of plasma processing equipment and discharging plasma excitation gas in order to generate plasma in the processing chamber 102, a porous gas circulator 114 having pores communicating in the direction of gas circulation is attached to a longitudinal hole 112 becoming the discharge passage of plasma excitation gas.