Abstract: A plasma monitoring system includes a gate valve disposed on a first side of a chamber, where the gate valve is opened or closed in conjunction with a plasma monitoring operation, a viewport structure disposed outside the chamber and including a plurality of light transmitting parts, and an optical emission spectroscopy disposed outside the chamber, where the optical emission spectroscopy monitors plasma by receiving plasma light transmitted through at least one of the plurality of light transmitting parts of the viewport structure.

Abstract: A wiring structure includes a substrate, a copper oxide layer having 16˜39 at % oxygen on the substrate and a copper layer on the copper oxide layer. The copper oxide layer has a thickness of 10-1000 ? and the copper layer has a thickness of 300-8000 ?. The copper layer and the copper oxide layer further have an alloy element less than 10 wt % and the alloy element is selected from the group of Ag, Ni, Mg, Zr, N.