Display substrate and method of manufacturing the same

A method of manufacturing a display substrate comprising:

• forming a gate metal pattern including a gate electrode on a base substrate;
• forming a gate insulation layer that covers the gate metal pattern;
• forming an active layer on the gate insulation layer;
• forming a source metal layer on the active layer;
• forming a photoresist layer on the source metal layer;
• developing the photoresist layer to form a first photoresist pattern;
• and
• forming an active pattern and a source metal pattern by etching the active layer and the source metal layer while using the first photoresist pattern as a mask,
• wherein forming the source metal layer comprises:
• depositing a first lower layer comprising molybdenum or molybdenum alloy on the active layer;
• depositing a third lower layer comprising molybdenum nitride;
• depositing a second lower layer comprising molybdenum or molybdenum alloy on the first lower layer;
• depositing a low-resistance metal layer comprising aluminum or aluminum alloy on the second lower layer;
• and
• depositing an upper layer comprising molybdenum or molybdenum alloy on the low-resistance metal layer, and
• wherein the source metal layer is etched by a fluorine-containing gas.