The scaling limit for VLSI gate oxide (SiO2) is 15-20 angstroms that is determined by the large direct-tunneling leakage current. Further scaling to improve device performance can be obtained using a higher dielectric constant material. We have studied the Al2O3 to use as an alternative gate dielectric. To ensure good quality, Al2O3 is thermally oxidized from MBE-grown AlAs or Al on Si-substrates. Experimental results indicate that the leakage current from oxidized AlAs is larger than that from directly oxidized Al, which may be due to the weak As2O3 inside Al2O3. The leakage current of a 53 angstroms Al2O3 is already lower than that of SiO2 with an equivalent oxide thickness of 21 angstroms.
|Number of pages||4|
|Journal||Journal of Crystal Growth|
|State||Published - 1 Jan 1999|
|Event||Proceedings of the 1998 10th International Conference on Molecular Beam Epitaxy (MBE-X) - Cannes|
Duration: 31 Aug 1998 → 4 Sep 1998