What are IC made of?
The black/bluish rectangle in the middle is the silicon die, and the IC's circuitry is visible as the pattern on the top. Moving outward, the colors in the 'well' surrounding the die may be oxidation on an adhesive layer that 'glues' the die to the plastic IC body or a metal chip carrier. These colors are pretty, but have no function. A metal chip carrier serves to support the chip, and provide a path for heat to be removed from the chip. Next, you can see very fine bonding wires that connect the die to metal paths (not easily visible here) that eventually emerge from the plastic chip body as pins. Illustration below from http://eee-books01.blogspot.com/2015/07/construction-of-dip-ic.html...