6 Why highK dielectrics are used in modern MOS technology 2

6- Why high-K dielectrics are used in modern MOS technology? (2 points) 7- hat is channel length modulation? (2 points)

Solution

6- USE OF High -K DIELECTRICS IN MODERN MOS TECHNOLOGY:

a) A gate with higher capacitance has more control of the electrons in the MOSFET compared to a low capacitance gate. A low capacitance gate can \"lose control\" of the electrons and cause the transistor to have poor characteristics like low drain breakdown voltage etc.

b) As transistors have decreased in size, the thickness of the silicon dioxide gate dielectric has steadily decreased to increase the gate capacitance and thereby drive current, raising device performance.

7-. CHANNEL LENGTH MODULATION:

a) Channel length modulation is nothing but reduction in the length of inverted channel region with increase in drain bias for large drain biases.

b) Because of this channel length modulation there exists an increase in current with drain bias with reduced output resistance.