Charge Transport and the Nature of Traps in Oxygen Deficient Tantalum Oxide

被引：47

作者：

Gritsenko, Vladimir A. ^{[1
,2
,3
]}

Perevalov, Timofey V. ^{[1
,2
]}

Voronkovskii, Vitalii A. ^{[1
]}

Gismatulin, Andrei A. ^{[1
]}

Kruchinin, Vladimir N. ^{[1
]}

Aliev, Vladimir Sh. ^{[1
]}

Pustovarov, Vladimir A. ^{[4
]}

Prosvirin, Igor P. ^{[5
]}

Roizin, Yakov ^{[6
]}

机构：

[1] RAS, Rzhanov Inst Semicond Phys SB, 13 Lavrentiev Ave, Novosibirsk 630090, Russia

[2] Novosibirsk State Univ, 2 Pirogov St, Novosibirsk 630090, Russia

[3] Novosibirsk State Tech Univ, 20 Prospekt K Marksa, Novosibirsk 630073, Russia

[4] Ural Fed Univ, Expt Phys Dept, 19 Mira Str, Ekaterinburg 620002, Russia

[5] RAS, Boreskov Inst Catalysis SB, 5 Lavrentiev Ave, Novosibirsk 630090, Russia

[6] TowerJazz, POB 619, IL-23105 Migdal Haemeq, Israel

来源：

ACS APPLIED MATERIALS & INTERFACES | 2018年 / 10卷 / 04期

基金：

俄罗斯科学基金会;

关键词：

Traps; oxygen vacancy; optic; XPS; ab initio simulation; photoluminescence; charge transport; GATE DIELECTRIC STACKS; TA2O5; FILMS; LAYER DEPOSITION; AMORPHOUS TA2O5; MEMORY; VACANCY; MECHANISMS; CHALLENGES; CONDUCTION;

D O I：

10.1021/acsami.7b16753

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Optical and transport properties of nonstoichiometric tantalum oxide thin films grown by ion beam deposition were investigated in order to understand the dominant charge transport mechanisms and reveal the nature of traps. The TaOx films composition was analyzed by X-ray photoelectron spectroscopy and by quantum-chemistry simulation. From the optical absorption and photoluminescence measurements and density functional theory simulations, it was concluded that the 2.75 eV blue luminescence excited in a TaOx by 4.45 eV photons, originates from oxygen vacancies. These vacancies are also responsible for TaOx conductivity. The thermal trap energy of 0.85 eV determined from the transport experiments coincides with the half of the Stokes shift of the blue luminescence band. It is argued that the dominant charge transport mechanism in TaOx films is phonon-assisted tunneling between the traps.

引用

页码：3769 / 3775

页数：7