IC Substrate, fully known as Integrated Circuit Substrate, is a micro-circuit board used to carry and connect integrated circuit chips (IC) with printed circuit boards (PCB). It serves as a bridge between the chip and the mainboard, acting as an indispensable key material and structure in advanced packaging technology.
Primary Functions of IC Substrate
- Support and protect the chip: Physically carries the chip, safeguarding it from damage.
- Electrical connection: Links IC chip pins (or solder balls) to the PCB via micro-fine traces, enabling signal and power transmission.
- Thermal management: Assists in dissipating heat from the chip to maintain its operating temperature.
- Enabling high-density packaging: Supports high-density, high-performance packaging methods such as BGA, CSP, and FC.
Types of IC Substrates
- BT Substrates: Primarily composed of BT resin, suitable for most general-purpose IC packaging.
- ABF Substrates: Utilizing ABF (Ajinomoto Build-up Film) material, ideal for high-density, high-speed chip packaging such as high-end CPUs, GPUs, and network chips.
- Ceramic Substrates: Employed in ultra-high-frequency, high-reliability applications like aerospace and military sectors.
Differences Between IC Substrates and Traditional PCBs
- Features finer traces, greater layer counts, smaller via apertures, and more complex manufacturing processes.
- Supports higher I/O density and stricter signal integrity requirements.