An interposer including a substantially planar substrate element with a slot formed therethrough. The slot, through which bond pads of a semiconductor die are exposed upon assembly of the interposer with the semiconductor die, includes a laterally recessed area formed in only a portion of a periphery thereof. The laterally recessed area is positioned so as to expose at least a portion of an active surface of the semiconductor die located between a bond pad located adjacent an outer periphery of the semiconductor die and the outer periphery. The laterally recessed area facilitates access to the bond pad by apparatus for forming, positioning, or securing intermediate conductive elements. Semiconductor device assemblies and packages that include the interposer are also disclosed, as are methods for assembling semiconductor device components with the interposer and methods for packaging such assemblies.