Question

Which dielectric materials in CMOS device structure lead to the increase of static power and which slow the circuits down as well as wasting dynamic power? Indicate how the high-k and low-k insulators of different kinds are needed to solve these problems.

Answer 1

We know that Capacitance is directly proportional to dielectric constant.

And Power disscipation is fCV² i.e. proportional to C.

Therefore High K dielectric Material like HfO2, ZrO2 are used as gate oxide of Mosfet increases power disscipation in Mosfet but increases the speed because of better gate coupling with the channel.

However interconnects where signals are transmitted are surrounded by low K dielectric material so as to reduce coupling between the various signal line.