Microcontact patterning of ruthenium gate electrodes by selective area atomic layer deposition

Patterned octadecyltrichlorosilane monolayers are used to inhibit film nucleation, enabling selective area atomic layer deposition (ALD) of ruthenium on SiO2 and HfO2 surfaces using bis-(cyclopentadienyl)ruthenium and oxygen. X-ray photoelectron spectroscopy indicated that OTS could deactivate film growth on thermal silicon oxide and hafnium oxide surfaces. The growth rate of ALD Ru is similar on various starting surfaces, but the growth initiation differed substantially. Metal-oxide- semiconductor capacitors were fabricated directly using the selective-area process. Capacitance measurements indicate the effective work function of ALD Ru is 4.84+/-0.1 eV on SiO2, and the effective work function is reduced on HfO2/SiO2 layers. (C) 2005 American Institute of Physics.