Methods and systems selectively irradiate structures on or within a semiconductor substrate using a plurality of laser beams. A diameter-reduced water passage 19 of a flow control member 20 disposed in a head portion 22 of a shower head body 12 has a first and a second water passage portions 40 and 41 provided on an entry side and an exit side thereof, respectively. The invention is configured to interpret special tags embedded within HTML encoded web pages.