Based on copper-made lead frame, Quad Flat No-lead (QFN) or microchip carrier (MCC) uses half-encapsulation technology to expose the rear side of the die pad and the tiny fingers, which are used to connect the chip and bonding wire with lead frame. The least interconnection makes the QFN packages competent to the applications over 12GHz working frequency, as well as the BCC packages. Providing both thermal and electrical enhancement, QFN is a cost-effective solution to leadless packaging due to its economical materials and simpler packaging process.