Here is something cool I found browsing the net:
For teaching a course I needed to take a closer look at a CPU. I asked around and got my hands on an old P-III Coppermine that was about to get thrown out. I’ll start with a disclaimer: I know virtually nothing about CPUs, so if I claim something to be true, it probably isn’t.
The first challenge is to get the actual silicon processor chip off of the plastic bonding board. In the picture below, the blue thing you see is the back side of the processor chip. When the processor is finished, it is turned upside down and bonded to the green circuit board. This allows the metal pads on the silicon chip and the pads on the circuit board to join, creating a connection (this is one of those claims…). I believe that the CPU at that stage is heated up in order to melt the joints and thereby solder them together.
Click images for full-size. Especially the scanning electron microscope images below could be interesting to view in all its splendor.
Original Source: http://www.sciencystuff.com/?p=24