US Patent 7709935 Reversible leadless package and methods of making and using same

A semiconductor device package includes an electrically conductive lead frame having a plurality of posts disposed at a perimeter of the package. Each of the posts has a first contact surface disposed at the first package face and a second contact surface disposed at the second package face. The lead frame also includes a plurality of post extensions disposed at the second package face. Each of the post extensions includes a bond site formed on a surface of the post extension opposite the second package face. At least one I/O pad on the semiconductor device is electrically connected to the post extension at the bond site using wirebonding, tape automated bonding, or flip-chip methods. The package can be assembled using a lead frame having pre-formed leads, with or without taping, or using partially etched lead frames. A stack of the semiconductor device packages may be formed.