| AVS 61st International Symposium & Exhibition | |
| Electronic Materials and Processing | Thursday Sessions |
| Session EM1-ThA |
| Session: | Materials for Quantum Computation |
| Presenter: | Andrew C. Kummel, University of California, San Diego |
| Authors: | T. Kent, University of California, San Diego T. Kaufman-Osborn, University of California, San Diego M. Edmonds, University of California, San Diego S.W. Park, University of California, San Diego J.H. Park, University of California, San Diego I.J. Kwak, University of California, San Diego E.A. Chagarov, University of California, San Diego P. Choudhury, New Mexico Institute of Mining and Technology R. Droopad, Texas State University A.C. Kummel, University of California, San Diego |
| Correspondent: | Click to Email |
For EOT scaling below 0.5 nm on FinFETs, it is necessary to nucleate the ALD in 99% of the unit cells on multiple crystallographic faces to obviate the requirement that the oxide overgrow non-reactive unit cells. (1) DFTMD calculations of high-k/InGaAs stacks annealed at 700K show that oxide bonding to each InGaAs surface atom in each cell is critical to avoid dangling bonds creating conduction band edge states; this requires high ALD nucleation by a metal precursor density follow by oxidation of any metal-metal bonds formed during nucleation.. For III-V semiconductors, experimental STM and STS studies show the in-situ exposure of just a few hundred Langmuirs of atomic H readily removes both group V and group III oxides from 001 and 110 surfaces allowing high nucleation density of metal ALD precursors. Concurrent MOSCAP studies show demonstrate sub 0.5 nm EOT gate oxides with low defect densities on InGaAs after in-situ cleaning and high nucleation density ALD. (2) DFTMD studies of the a-Al2O3/SiGe(001) stack show that the SiGe(001) interface with Si termination (a-Al2O3/Si-SiGe(001)) has a superior electronic structure to the interface with Ge termination (a-Al2O3/Ge-SiGe(001). Silicon termination of SiGe should also be highly favorable for forming gas passivation of dangling bonds. For SiGe(001) a novel technique has been develop to produce surface which will mimic the good passivation properties of Si(001) by terminating the surface in a monolayer of Si-OH which will react with nearly any metal ALD precursor. (3) While group IV and III-V semiconductors can be nucleated by covalent bonds, 2D semiconductors require a different approached. DFTMD simulation studies show the metal coordination complexes can readily chemisorb on 2D semiconductor via non-bonding interaction and they can covalent bond multiple TMA molecules consistent with a submolecular nucleation density. A technique has been develop for functionalize 2D semiconductors with a phthalocyanine, and it has been demonstrated it can nucleate insulation sub 1nm gate oxide growth.