It looks just like this.
Wiki says it's called a chip on a board. A carrierless chip that is protected with epoxy.
AH! My error.
No That isn't C5 mounting. That is mounting the DIE directly to the PC board. Mother M stayed away from direct mounting. The problem they saw with direct mounting was the difference in the thermal expansion characteristics of silicon die and glass or poly boards caused the wire bonds to break. However they were temperature testing to mil specs...the bonding had to survive very wide temperature variations. Which would not apply to consumer electronics.
Bits you are right...that is a huge chip bonded directly to the board. It is high tech just from the shear size. I would like to see the wire bonder for that.