Choosing the right material for RF packaging

摘要

While semiconductors tend to capture people's attention far more than their packaging, a die and its packaging are inseparable. The success of a device - especially an RF or microwave device - often depends on both. The choice of packaging material for interconnects involving printed circuit boards and devices, often referred to as Level 2 and 3 packaging, depends on many factors: in addition to assuring a viable interconnect, it may also need to provide for downstream testing and processing, compatibility with other components, in-use thermal management, and environmental-stress protection, among other functions. Level 2 and 3 packaging is meet din usually made from epoxy-molding compound (EMC), ceramic, metal, or engineering thermoplastic. EMC is used to provide complete chip encapsulation, while the other materials create open-cavity packages when dies cannot be encapsulated. The choice of material is most often driven by economics and the need for optimum yield and performance. EMC transfer-molded packaging, which accounts for nearly all Level 2 and 3 packaging, is often the least expensive option.