In simple terms, it is a technology that uses insulating materials to encapsulate integrated circuit dies, enabling electrical connections. As a critical link between wafer manufacturing and end-use applications, it directly impacts chip performance, size and cost.

Five Core Functions of Packaging

• Physical Protection: Isolates moisture and dust to prevent chip damage

• Electrical Interconnection: Connects chips to PCBs for signal transmission and power supply

• Thermal Management: Dissipates chip heat to ensure stable operation

• Mechanical Support: Protects fragile Silicon Wafers and facilitates subsequent soldering and testing

• Standardized Interface: Uniform package outline and pins to simplify integration and production

Five Stages of Packaging Technology Development

• Through-Hole Mounting (Before 1970): DIP packages, easy for manual soldering, large in size with limited pins

• Surface Mount Technology (1980s): SOP, QFP, compact size suitable for automation with increased pin density

• Area Array Packaging (1990s): BGA, CSP, solder ball distribution for greatly improved pin density

• Chip/System-Level Packaging (2000s): FC, SiP, package size close to die size with multi-chip integration capability

• Advanced Packaging (From 2010 to Present): 2.5D/3D IC, CoWoS, vertical stacking to extend beyond Moore's Law

Common Package Types

• DIP: Widely used in early microcontrollers, user-friendly for manual soldering, relatively large

• SOP: Surface-mount, compact size, suitable for memory and power ICs

• QFP: Quad flat package with high pin density, ideal for complex chips but difficult to solder

• BGA: Bottom solder balls with extremely high pin count, preferred for CPUs and GPUs, challenging to rework

• CSP: Near-die size packaging, suitable for smartphone processors and sensors

Key Advanced Packaging (Critical in Post-Moore Era)

• 2.5D Packaging (CoWoS, EMIB): Multi-chip side-by-side integration with high bandwidth and high yield

• 3D Packaging: Vertical stacking for smaller size and lower latency, with thermal challenges

• SiP: Integrates multiple chips in one package to achieve system-level functionality