Quad-flat no-leads (QFN) packages are commonly used for RF applications to connect integrated circuits (ICs) to printed-circuit boards (PCBs). The benefits associated with QFN packages include low cost, a small form factor, and good electrical and thermal performance. QFN packages come in various sizes, typically ranging from 3 × 3 mm to 9 × 9 mm.
One company that manufactures QFN packages is Barry Industries, which offers versions rated to 40 GHz. In contrast to plastic QFN packages, Barry builds high-temperature co-fired-ceramic (HTCC) versions that feature low-loss broadband transitions, allowing for superior performance over frequency. These packages also withstand much greater temperatures than plastic QFN packages and can be sealed hermetically.