A method for a through-silicon-via (TSV) connector includes: providing a semiconductor wafer with a silicon substrate, wherein the semiconductor wafer has a frontside and a backside opposite to the frontside thereof; forming multiple holes in the silicon substrate of the semiconductor wafer; forming a first insulating layer at a sidewall and bottom of each of the holes; forming a metal layer over the semiconductor wafer and in each of the holes; polishing the metal layer outside each of the holes to expose a frontside surface of the metal layer in each of the holes; forming multiple metal bumps or pads each on the frontside surface of the metal layer in at least one of the holes; grinding a backside of the silicon substrate of the semiconductor wafer to expose a backside surface of the metal layer in each of the holes, wherein the backside surface of the metal layer in each of the holes and a backside surface of the silicon substrate of the semiconductor wafer are coplanar; and cutting the semiconductor wafer to form multiple through-silicon-via (TSV) connectors.