Advanced transistors (FinFET and GAA)
Which correctly describes EOT (equivalent oxide thickness)?
- AThe thickness of an SiO2 film that would give the same gate capacitance as a gate insulator such as a high-k film
- BThe actual physical thickness of the gate insulator
- CThe thickness of the wiring layers
Show answer and explanation
Answer: A. The thickness of an SiO2 film that would give the same gate capacitance as a gate insulator such as a high-k film
EOT converts the gate capacitance of a gate insulator into the SiO2 thickness that would give the same capacitance. A high-k film with about five times the permittivity of SiO2 gives the same capacitance at a physical thickness about five times the EOT, and the thicker film suppresses tunneling current.