Bumpless Build-up Layer or BBUL is a

processor Processor may refer to: Computing Hardware * Processor (computing) **Central processing unit (CPU), the hardware within a computer that executes a program *** Microprocessor, a central processing unit contained on a single integrated circuit (I ...

packaging technology developed by

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 ser ...

. It is bumpless, because it does not use the usual tiny

solder Solder (; NA: ) is a fusible metal alloy used to create a permanent bond between metal workpieces. Solder is melted in order to wet the parts of the joint, where it adheres to and connects the pieces after cooling. Metals or alloys suitable ...

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 A die, in the context of integrated circuits, is a small block of semiconducting material on which a given functional circuit is fabricated. Typically, integrated circuits are produced in large batches on a single wafer of electronic-grade sili ...

. The usual way is to manufacture them separately and bond them together. It was presented in October 2001. It should have been a key component in the 8 GHz and 15 GHz processors that should have been in the market by 2005 and 2007 respectively.''Tom's Hardware'', Intel delays BBUL processor package, JANUARY 13, 2005
/ref> Also 20 GHz should have been possible before the year 2010. The BBUL is not needed yet because there is no longer the clock-frequency competition.

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

Bumpless Build-Up Layer Packaging

References

Intel microprocessors {{microcompu-stub