Abstract

A high-k dielectric film is provided which remains amorphous at relatively high annealing temperatures. The high-k dielectric film is a metal oxide of either Zr or Hf, doped with a trivalent metal, such as Al. Because the film resists the formation of a crystalline structure, interfaces to adjacent films have fewer irregularities. When used as a gate dielectric, the film can be made thin to support smaller transistor geometries, while the surface of the channel region can be made smooth to support high electron mobility. Also provided are CVD, sputtering, and evaporation deposition methods for the above-mentioned, trivalent metal doped high dielectric films.

Other References

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