Bumpless Build-up Layer

Bumpless Build-up Layer or BBUL is a processor packaging technology developed by Intel. It is bumpless, because it does not use the usual tiny solder bumps to attach the silicon die to the processor package wires. It has build-up layers, because is grown or built up around the silicon die. The usual way is to manufacture them separately and bond them together.

It was presented in October 2001.

Advantages

• Thinner and lighter.
• Higher performance and lower power.
• Higher interconnect density. C4 bumps were reaching their limits.
• Better signal routing capability.
• Allows many chips in the same package.

External links

• BBUL Packaging
• Intel to delay Bumpless Build-up Layer processor package
• Bumpless Build-Up Layer Packaging