Multichip packages or multichip modules may include stacked chips and through silicon/substrate vias (TSVs) formed using enclosure-first technology. Enclosure-first technology may include forming an isolation enclosure associated with a TSV early in the fabrication process, without actually forming the associated TSV. The TSV associated with the isolation enclosure is formed later in the fabrication process. The enclosure-first technology allows the isolation enclosures to be used as alignment marks for stacking additional chips. The stacked chips can be connected to each other or to an external circuit such that data input is provided through the bottom-most (or topmost) chip, data is output from the bottom-most (or topmost) chip. The multichip package may provide a serial data connection, and a parallel connection, to each of the stacked chips.