Metal gate electrodes for rare earth oxide high-k dielectrics

Abstract

A FUSI NiSi metal gate technology is used to investigate the scaling potential of high-k epitaxial gadolinium oxide (Gd 203 ) down to 0.6 nm equivalent oxide thickness. Thermally stable gate stacks have been realized by TiN electrodes on gadolinium silicate. Work function tuning of mid gap electrodes is achieved by insertion of ultrathin AIN buffer layers. Initial results based on sputtered buffer layers are transferred to atomic layer deposition technique in order to achieve atomic control of the thicknesses in combination with conformal deposition.

Crystalline Gadolinium Oxide: A Promising High-k Candidate for Future CMOS Generations

“…The TiN gate electrode has been deposited in an atomic layer deposition (ALD) process based on a TiCl 4 precursor in combination with hydrogen plasma. With a thin additional ALD aluminum nitride (AlN) buffer layer one can control the work function of the TiN gate electrodes (2). The fabricated devices are bulk-Si long channel devices.…”