The phrase "metal–oxide–semiconductor" is a reference to the physical structure of MOS field-effect transistors, having a metal gate electrode placed on top of an oxide insulator, which in turn is on top of a semiconductor material. Aluminium was once used but now the material is polysilicon. Other metal gates have made a comeback with the advent of high-κ dielectric materials in the CMOS process, as announced by IBM and Intel for the 45 nanometer node and smaller sizes.
the phrase "metal–oxide–semiconductor" is a reference to the physical structure of mos field-effect transistors having a metal gate electrode placed on top of an oxide insulator which in turn is on top of a semiconductor material aluminium was once used but now the material is polysilicon other metal gates have made a comeback with the advent of high-κ dielectric materials in the cmos process as announced by ibm and intel for the 45 nanometer node and smaller sizes