Gate dielectric

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Gate dielectric" – news · newspapers · books · scholar · JSTOR (December 2006) (Learn how and when to remove this template message)

A gate dielectric is a dielectric used between the gate and substrate of a field-effect transistor (such as a MOSFET). In state-of-the-art processes, the gate dielectric is subject to many constraints, including:

• Electrically clean interface to the substrate (low density of quantum states for electrons)
• High capacitance, to increase the FET transconductance
• High thickness, to avoid
  quantum tunneling
  .

The capacitance and thickness constraints are almost directly opposed to each other. For silicon-substrate FETs, the gate dielectric is almost always silicon dioxide (called "gate oxide"), since thermal oxide has a very clean interface. However, the semiconductor industry is interested in finding alternative materials with higher dielectric constants, which would allow higher capacitance with the same thickness.

History

The earliest gate dielectric used in a field-effect transistor was

• QBD (electronics)

References

This electronics-related article is a stub. You can help Wikipedia by expanding it.

• v
• t
• e