Definition: CMOS

(Complementary Metal Oxide Semiconductor) Pronounced "c-moss," CMOS is the most widely used integrated circuit technology and is found in almost every electronic product from handheld devices to mainframes. CMOS uses PMOS and NMOS transistors wired in a balanced fashion to save power because almost none is used except when switching between on and off. However, there is a minuscule power leakage.

The first transistors were bipolar, which are still used when higher power is required, and both types are sometimes used in the same device (see BiCMOS). See MOSFET, FET, FinFET, CFET, bipolar transistor, CMOS memory and process technology.

A Note From the Author

In the early 1980s, my wife Irma and I had a kitten at the beach I named CMOS. When we introduced her to friends, everyone thought "sea moss" was such a cute name for a beach cat. However, when I told them the cat's name was really complementary metal oxide semiconductor, they didn't come around much any more!