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

fYear

2014

fDate

13-15 Oct. 2014

Firstpage

59

Lastpage

62

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;

fLanguage

English

Publisher

ieee

Conference_Titel

Semiconductor Conference (CAS), 2014 International

Conference_Location

Sinaia

ISSN

1545-827X

Print_ISBN

978-1-4799-3916-9

Type

conf

DOI

10.1109/SMICND.2014.6966390

Filename

6966390