Thin Solid Films, Vol.517, No.18, 5543-5547, 2009
Low temperature atomic layer deposition of high-k dielectric stacks for scaled metal-oxide-semiconductor devices
Dielectric stacks of aluminium oxide and zirconium oxide grown by atomic layer deposition at low temperatures between 110 degrees C and 200 degrees C from trimethylaluminum/water and tetrakis-(diethylamino)zirconium/water, respectively, are investigated regarding their applicability in Metal-Oxide-Semiconductor (MOS) devices. We characterize the dielectric stacks regarding their electrical qualification in MOS devices and their thermodynamical behaviour, and refer these results to layer structure and morphology. As a result, we can show that the deposition of the stacks at low temperatures (110 degrees C to 150 degrees C) in combination with reductive/oxidative post-deposition annealing lead to amorphous dielectrics with remarkably high permittivity, with very low leakage currents in the range of 10(-7) A/cm(2), and excellent capacitance-voltage characteristics. (C) 2009 Elsevier B.V. All rights reserved.
Keywords:Atomic layer deposition;High dielectric constant;Zirconium oxide;Aluminum oxide;Electrical properties and measurements;Transmission eletron microscopy