Integrating the formation of I/O and core MOS devices with MOS capacitors and resistors

摘要

An integrated circuit structure includes a semiconductor substrate, and a first and a second MOS device. The first MOS device includes a first gate dielectric over the semiconductor substrate, wherein the first gate dielectric is planar; and a first gate electrode over the first gate dielectric. The second MOS device includes a second gate dielectric over the semiconductor substrate; and a second gate electrode over the second gate dielectric. The second gate electrode has a height greater than a height of the first gate electrode. The second gate dielectric includes a planar portion underlying the second gate electrode, and sidewall portions extending on sidewalls of the second gate electrode.