METHOD OF MAKING LIGHT EMITTING DISPLAY DEVICE

A method for manufacturing a light emitting display device is provided to reduce a process time and a process time by forming a via hole through one mask. A first insulating layer(152) is formed on a substrate(150) in which a thin film transistor(151) is formed. A second insulating layer(153) is formed on the first insulating layer. A second insulating layer is patterned. The second insulating layer is made of one of acryl, and the acryl series and the polyimide series organic compound. A part of the first insulating layer is exposed. The exposed firsts insulating layer is etched. The etching is performed by the oxygen plasma. A source electrode or a drain electrode of the thin film transistor is exposed. The cooling gas is supplied to the substrate. The cooling gas is the helium gas. The ashing of the surface of the second insulating layer is performed.