Title :
Charge storage properties of HfO2/Ge-HfO2/SiO2 trilayer structures
Author :
Palade, Catalin ; Slav, Adrian ; Lepadatu, Ana-Maria ; Teodorescu, Valentin Serban ; Ciurea, Magdalena Lidia
Author_Institution :
Nat. Inst. of Mater. Phys., Magurele, Romania
Abstract :
We report on the charge storage properties of trilayer structures consisting in sputtered gate HfO2/co-sputtered Ge-HfO2 layer/rapid thermal tunneling SiO2 oxide. Investigations of transmission electron microscopy and X-ray diffraction evidence the formation of HfO2 with mixed structure of monoclinic and tetragonal in the annealed structures. Capacitance-voltage (C-V) characteristics were measured on Al/HfO2/Ge-HfO2/SiO2/Si/Al metal-oxide-semiconductor capacitors based on as-deposited and annealed structures. Large C-V hysteresis is observed for the as-deposited structures and is controlled by traps present in oxide and interface. The annealing yields a C-V hysteresis with smaller memory window being due to injected charges in Ge nanocrystals.
Keywords :
MOS capacitors; X-ray diffraction; aluminium; capacitance; elemental semiconductors; germanium; hafnium compounds; high-k dielectric thin films; multilayers; nanofabrication; nanostructured materials; rapid thermal annealing; silicon; silicon compounds; sputter deposition; sputtered coatings; thin film capacitors; transmission electron microscopy; Al-HfO2-Ge-HfO2-SiO2-Si-Al; C-V hysteresis; Ge nanocrystals; X-ray diffraction; annealed structures; as-deposited structures; capacitance-voltage characteristics; charge storage properties; injected charges; memory window; metal-oxide-semiconductor capacitors; monoclinic mixed structure; sputtered gate HfO2-cosputtered Ge-HfO2 layer-rapid thermal tunneling SiO2 oxide; tetragonal mixed structure; transmission electron microscopy; trilayer structures; Films; Hafnium compounds; Hysteresis; Nanocrystals; Rapid thermal annealing; Silicon; Ge nanocrystals; HfO2; charge storage; magnetron sputtering;
Conference_Titel :
Semiconductor Conference (CAS), 2014 International
Conference_Location :
Sinaia
Print_ISBN :
978-1-4799-3916-9
DOI :
10.1109/SMICND.2014.6966390
