Panel Level Packaging

Both are advanced semiconductor packaging methods. In PLP, chips are assembled on large rectangular panels instead of round wafers, unlike WLP, which is limited to the size of silicon wafers (typically up to 300mm), PLP allows for larger surface areas, increasing productivity and reducing cost per chip. This method supports greater scalability and flexibility in layout for high-volume production.

Fan-out panel-level packaging (FOPLP) offers several advantages over traditional packaging that make it an efficient and scalable solution for next-generation electronic devices. It enables thinner, lighter packages with better thermal and electrical performance, and larger panel sizes let more chips be processed simultaneously—delivering a lower cost per unit. In addition, FOPLP is ideal for high-density applications, as it supports finer line widths and tighter pitches.

Common PLP materials include epoxy molding compounds, photoresists, redistribution layers (RDLs) made of copper, and dielectric materials such as polyimide or epoxy. During processing, substrates often consist of temporary carrier materials such as glass or silicon. For final packaging, however, organic laminate panels are commonly used, as they provide high thermal stability and mechanical strength, and are compatible with fine-line lithography and high-density interconnects (HDI).

The FOPLP process involves several key steps, including wafer fabrication, reconstitution and panelization, redistribution layer (RDL) fabrication, die placement, molding, and final dicing. Die are placed on a carrier and molded into a panel, which is thinned and planarized to prepare for RDL formation. Fine-line metallization and dielectric layering enable high-density interconnects. Finally, the panel is singulated into individual packages. Throughout the process, surface cleaning, wet processing, and stress-free planarization (SFP) are critical for maintaining uniformity and yield.

FOPLP is gaining traction as system integration and miniaturization become more important for a broad range of markets. The process is best suited for applications that demand high performance and compact form factors, including smartphones, tablets, and wearable devices, as well as automotive electronics, 5G infrastructure, and advanced computing applications such as artificial intelligence (AI) and high-performance computing (HPC).