CMOS structure?

Answer 1

CMOS - Complementary Metal Oxide Substrate. Uses two power supplies, one positive and the other negative when referenced to ground. This gives "op amps" more power out by algebraically adding the two out puts together causing a complimentary symmetry (or floating ground) out put.
The structure, on the substrate, uses both PNP and NPN semi-conductors in a mirrored configuration.

Answer 2

what do you mean CMOS structure?
it is something like composite metal oxide semi conductor...