Type of bumpless and wireless semiconductor device

According to a first aspect of the present invention there is provided a semiconductor device comprising: a die having a central active region, a top surface, a bottom surface, and sidewalls having a plurality of perforations therein, each perforation extending from a top end at the top surface to a bottom end at the bottom surface; a plurality of die pads on the top surface and extending from the central active region to respective top ends; a patterned back-side-metallization layer on the bottom surface, comprising a plurality of electrically isolated regions extending to respective bottom ends; metal coating partially filling the perforations and providing electrical connection between respective ones of the plurality of die pads and respective ones of the plurality of electrically isolated regions; and a passivation layer covering the top surface and the die pads.