Advanced transistors (FinFET and GAA)

What does the "k" in "high-k gate dielectric" represent?

  1. ACrystal hardness
  2. BThermal conductivity
  3. CRelative permittivity (dielectric constant)
Show answer and explanation

Answer: C. Relative permittivity (dielectric constant)

The k in high-k denotes the relative permittivity, and high-k materials are insulators with a higher relative permittivity than SiO2 (about 3.9). A typical example is hafnium-based oxide (relative permittivity around 20), which gives a large gate capacitance even with a physically thick film.

  • A. It does not stand for hardness.
  • B. It does not stand for thermal conductivity.
  • C. Correct. k represents the relative permittivity.
Practice this topic Back to topic

More Advanced transistors (FinFET and GAA) questions

  1. For a FinFET whose fin is 50 nm tall and 6 nm wide, which is closest to the effective channel width per fin (the perimeter wrapped by the gate)?
  2. To adequately suppress short-channel effects in a FinFET, what is generally required of the fin width?
  3. In high-k/metal gate transistors, why is a very thin layer such as SiO2 often placed between the silicon and the high-k film (such as hafnium oxide)?
  4. Why have III-V compound semiconductors such as InGaAs been researched as future nMOS channel materials?
  5. Which correctly describes the transistor performance metric "Ion/Ioff ratio"?