Patent ID: 7180198

Claim:
A switching device comprising: a substrate including a first region and a second region surrounding the first region; a plurality of align key patterns of polycrystalline silicon on the substrate in the second region to form a plurality of convex align keys, the plurality of convex align keys having slope against the substrate; an active layer of polycrystalline silicon on the substrate in the first region, the active layer including a channel region and source and drain regions at sides of the channel region; a gate insulating layer on the active layer; a gate electrode on the gate insulating layer; an interlayer insulating layer on the gate electrode, the interlayer insulating layer including a first contact hole exposing the source region and a second contact hole exposing the drain region; and source and drain electrodes on the interlayer insulating layer, the source electrode being connected to the source region through the first contact hole and the drain electrode being connected to the drain region through the second contact hole.