Optical properties and structural characteristics of ZnMgO grown by plasma assisted molecular beam epitaxy

被引：101

作者：

Wassner, Thomas A. ^{[1
]}

Laumer, Bernhard ^{[1
]}

Maier, Stefan ^{[1
]}

Laufer, Andreas ^{[2
]}

Meyer, Bruno K. ^{[2
]}

Stutzmann, Martin ^{[1
]}

Eickhoff, Martin ^{[2
]}

机构：

[1] Tech Univ Munich, Walter Schottky Inst, D-85748 Garching, Germany

[2] Univ Giessen, Inst Phys 1, D-35392 Giessen, Germany

来源：

JOURNAL OF APPLIED PHYSICS | 2009年 / 105卷 / 02期

关键词：

buffer layers; deep levels; defect states; excitons; II-VI semiconductors; lattice constants; molecular beam epitaxial growth; photoluminescence; plasma materials processing; semiconductor growth; semiconductor thin films; spectral line shift; wide band gap semiconductors; zinc compounds; MG(X)ZN1-XO ALLOYS; UNDOPED ZNO; THIN-FILMS; EXCITON; LAYERS; IMPURITIES; CRYSTALS; SPECTRA; MBE;

D O I：

10.1063/1.3065535

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Wurtzite Zn(1-x)Mg(x)O thin films with Mg contents between x=0 and x=0.37 were grown on c-plane sapphire substrates by plasma assisted molecular beam epitaxy using a MgO/ZnMgO buffer layer. The a-lattice parameter is independent from the Mg concentration, whereas the c-lattice parameter decreases from 5.20 A for x=0 to 5.17 A for x=0.37, indicating pseudomorphic growth. The near band edge photoluminescence shows a blueshift with increasing Mg concentration to an emission energy of 4.11 eV for x=0.37. Simultaneously, the energetic position of the deep defect luminescence shows a linear shift from 2.2 to 2.8 eV. Low temperature transmission measurements reveal strong excitonic features for the investigated composition range and alloy broadening effects for higher Mg contents. The Stokes shift as well as the Urbach energy is increased to values of up to 125 and 54 meV for x=0.37, respectively, indicating exciton localization due to alloy fluctuations.

引用

页数：6

共 42 条

[1] Infrared dielectric functions and phonon modes of high-quality ZnO films [J].

Ashkenov, N ;

Mbenkum, BN ;

Bundesmann, C ;

Riede, V ;

Lorenz, M ;

Spemann, D ;

Kaidashev, EM ;

Kasic, A ;

Schubert, M ;

Grundmann, M ;

Wagner, G ;

Neumann, H ;

Darakchieva, V ;

Arwin, H ;

Monemar, B .

JOURNAL OF APPLIED PHYSICS, 2003, 93 (01) :126-133

[2] FARADAY ROTATION IN ZNO - DETERMINATION OF ELECTRON EFFECTIVE MASS [J].

BAER, WS .

PHYSICAL REVIEW, 1967, 154 (03) :785-+

[3] Exciton freeze-out and thermally activated relaxation at local potential fluctuations in thick AlxGa1-xN layers [J].

Bell, A ;

Srinivasan, S ;

Plumlee, C ;

Omiya, H ;

Ponce, FA ;

Christen, J ;

Tanaka, S ;

Fujioka, A ;

Nakagawa, Y .

JOURNAL OF APPLIED PHYSICS, 2004, 95 (09) :4670-4674

[4] Lattice vibrational properties of ZnMgO grown by pulsed laser deposition [J].

Belogorokhov, A. I. ;

Polyakov, A. Y. ;

Smirnov, N. B. ;

Govorkov, A. V. ;

Kozhukhova, E. A. ;

Kim, H. S. ;

Norton, D. P. ;

Pearton, S. J. .

APPLIED PHYSICS LETTERS, 2007, 90 (19)

[5] A UNIVERSAL TREND IN THE BINDING-ENERGIES OF DEEP IMPURITIES IN SEMICONDUCTORS [J].

CALDAS, MJ ;

FAZZIO, A ;

ZUNGER, A .

APPLIED PHYSICS LETTERS, 1984, 45 (06) :671-673

[6] FLUORESCENCE LINE NARROWING, LOCALIZED EXCITON-STATES, AND SPECTRAL DIFFUSION IN THE MIXED SEMICONDUCTOR CDSXSE1-X [J].

COHEN, E ;

STURGE, MD .

PHYSICAL REVIEW B, 1982, 25 (06) :3828-3840

[7] Excitonic transitions in ZnO/MgZnO quantum well heterostructures [J].

Coli, G ;

Bajaj, KK .

APPLIED PHYSICS LETTERS, 2001, 78 (19) :2861-2863

[8] THE OPTICAL-PROPERTIES OF COPPER IN ZINC-OXIDE [J].

DEAN, PJ ;

ROBBINS, DJ ;

BISHOP, SG ;

SAVAGE, JA ;

PORTEOUS, P .

JOURNAL OF PHYSICS C-SOLID STATE PHYSICS, 1981, 14 (20) :2847-2858

[9] High-quality ZnO layers grown by MBE on sapphire [J].

El-Shaer, A ;

Mofor, AC ;

Bakin, A ;

Kreye, M ;

Waag, A .

SUPERLATTICES AND MICROSTRUCTURES, 2005, 38 (4-6) :265-271

[10] ZnMgO epilayers and ZnO-ZnMgO quantum wells for optoelectronic applications in the blue and UV spectral region [J].

Gruber, T ;

Kirchner, C ;

Kling, R ;

Reuss, F ;

Waag, A .

APPLIED PHYSICS LETTERS, 2004, 84 (26) :5359-5361

← 1 2 3 4 5 →