AVS 64th International Symposium & Exhibition
    Electronic Materials and Photonics Division Monday Sessions
       Session EM-MoA

Paper EM-MoA6
Interface Engineering with Al2O3-HfO2 Nanolaminate Gate oxides on Silicon Germanium

Monday, October 30, 2017, 3:20 pm, Room 14

Session: Novel Materials and Devices for Electronics
Presenter: Mahmut Kavrik, University of California at San Diego
Authors: M. Kavrik, University of California at San Diego
K. Tang, Stanford University
E. Thomson, University of California at San Diego
J. Cheng, University of California at San Diego
A.C. Kummel, University of California at San Diego
Correspondent: Click to Email
Silicon Germanium (SiGe) alloys are promising alternative for silicon in semiconductor industry due to their tunable bandgap and carrier mobility through variation in composition. However, replacement of Si with SiGe requires a new class of high-k dielectric gate oxides with low leakage current for CMOS processing. Germanium content in semiconductor induces new interface defects due to its bonding with oxygen; GeOx is soluble in water and also can out diffuse into the gate oxide. Al2O3 and HfO2 oxides were incorporated into nanolaminate stacks on the SiGe by Atomic Layer Deposition (ALD). Al2O3 was deposited with organic precursor trimethylaluminum (TMA) and H2O on SiGe at 250C after HF and sulfur surface treatments. Sulfur treatment forms Ge-S and Ge-S-Ge bonds and prevents GeOx formation. Subsequently, HfO2 oxide layers were grown with organic precursor Tetrakis(dimethylamido) hafnium(TDMAH) and H2O at 250C. Al2O3-HfO2 nanolaminates were terminated with one layer of Al2O3 to protect oxide from gate metal damage. MOSCAP studies showed low Dit with hig Cox with Nanolaminate structure.