A gas discharge chamber that uses a calcium fluoride crystal which reduces a breakage due to mechanical stress, thermal stress from light absorption, and the like, increases the degree of linear polarization of output laser, and suppresses degradation due to strong ultraviolet laser light irradiation. A second, front-mounted nozzle is coupled to the first nozzle by a nozzle link that is provided between the first and second nozzles. An oversized lid is affixed to the substrate. The expansion module is constructed and arranged to actuate a sizing mandrel, which is inserted into the interior of the end of a tube to expand the diameter of the end of that tube. With such a lower switching voltage in the SCR device, the total layout area of the ESD protection circuit can be reduced, and the turn-on speed of SCR device is further improved to quickly discharge ESD current.