Charge-carrier transport and recombination in heteroepitaxial CdTe

被引：33

作者：

Kuciauskas, Darius ^{[1
]}

Farrell, Stuart ^{[1
]}

Dippo, Pat ^{[1
]}

Moseley, John ^{[1
]}

Moutinho, Helio ^{[1
]}

Li, Jian V. ^{[1
]}

Motz, A. M. Allende ^{[1
]}

Kanevce, Ana ^{[1
]}

Zaunbrecher, Katherine ^{[1
]}

Gessert, Timothy A. ^{[1
]}

Levi, Dean H. ^{[1
]}

Metzger, Wyatt K. ^{[1
]}

Colegrove, Eric ^{[2
]}

Sivananthan, S. ^{[2
]}

机构：

[1] Natl Renewable Energy Lab, Golden, CO 80401 USA

[2] Univ Illinois, Microphys Lab, Dept Phys, Chicago, IL 60612 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2014年 / 116卷 / 12期

关键词：

MOLECULAR-BEAM EPITAXY; SURFACE RECOMBINATION; GROWN CDTE; MICROSCOPY; GAAS; HETEROSTRUCTURES; LUMINESCENCE; DYNAMICS; LIFETIME; BULK;

D O I：

10.1063/1.4896673

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We analyze charge-carrier dynamics using time-resolved spectroscopy and varying epitaxial CdTe thickness in undoped heteroepitaxial CdTe/ZnTe/Si. By employing one-photon and nonlinear two-photon excitation, we assess surface, interface, and bulk recombination. Two-photon excitation with a focused laser beam enables characterization of recombination velocity at the buried epilayer/substrate interface, 17.5 mu m from the sample surface. Measurements with a focused two-photon excitation beam also indicate a fast diffusion component, from which we estimate an electron mobility of 650 cm(2) (Vs)(-1) and diffusion coefficient D of 17 cm(2) s(-1). We find limiting recombination at the epitaxial film surface (surface recombination velocity S-surface - (2.8 +/- 0.3) x 10(5) cm s(-1)) and at the heteroepitaxial interface (interface recombination velocity S-interface - (4.8 +/- 0.5) x 10(5) cm s(-1)). The results demonstrate that reducing surface and interface recombination velocity is critical for photovoltaic solar cells and electronic devices that employ epitaxial CdTe. (C) 2014 AIP Publishing LLC.

引用

页数：8

共 36 条

[1] Interface recombination velocity measurement by a contactless microwave technique [J].