Gate Conductive Layer Wire Pad Formation in Display Devices

The patent combines the formation of wire pads and contact holes into a single patterning process. The gate conductive layer is patterned to simultaneously define both the wire pad regions and contact hole positions, eliminating the need for separate mask processes that would otherwise be required for these features.

The gate conductive layer serves multiple functions: it acts as the gate electrode for the transistor, forms the wire pad for external connections, and defines the contact hole positions. This multi-functionality reduces the number of separate patterning operations needed.

The gate capping layer acts as an intermediary protective barrier between the gate conductive metal layer and reactive chemicals. This capping layer is specifically designed to resist corrosion from etchants and other reactive substances used in subsequent patterning processes, thereby protecting the underlying conductive layer.

The gate capping layer is deposited beforehand to provide protective cushioning against future exposure to harmful chemicals. This preventive measure ensures that even if wire pads are exposed to reactive chemicals during later mask processes, the conductive metal layer remains protected from corrosion.

The protective capping layer formation is merged with the gate electrode fabrication process. The same gate conductive layer that forms the transistor gate also forms the wire pad, and the capping layer protects both functions simultaneously, eliminating the need for separate protective measures.

The gate capping layer serves dual purposes: it protects the gate conductive metal layer from corrosion during mask processes, and it also serves as part of the wire pad structure itself. This multi-functionality eliminates the need for additional protective processes.