An alignment apparatus for aligning a wafer includes a mounting unit, an imaging unit, an elevation unit, and a controlling unit. The traction surface may include a plurality of chain assemblies or alternatively a plurality of pointed lugs. The wall bracket cover nests within the wall mount bracket and prevents access to the heads of the lag bolts. The first type ion-doped buried layer is in the substrate underneath the first type ion-doped well. When a call from another line has arrived during communications, the lines are switched according to a switching instruction from the user and the line through which the communications have been performed is automatically turned to be on hold.