In situ study of porous silicon thin films thermal oxidation by pulsed laser photoacoustics

Porous silicon (PSi) on p++-type (111) silicon substrate has been fabricated by electronically etching method in hydrofluoric acid (HF) media from 5 to 110 mA/cm2 of anodizing current density. The problem of determining the optical properties of (111) PSi is board through implementing a photoacoustic (PA) technique coupled to an electrochemical cell for real-time monitoring of the formation of porous silicon thin films. PA amplitude allows the calculation of the real part of the films refractive index and porosity using the reflectance self-modulation due to the interference effect between the PSi film and the substrate that produces a periodic PA amplitude. The optical properties are studied from specular reflectance measurements fitted through genetic algorithms, transfer matrix method (TMM), and the effective medium theory, where the Maxwell Garnett (MG), Bruggeman (BR), and Looyenga (LLL) models were tested to determine the most suitable for pore geometry and compared with the in situ PA method. It was found that (111) PSi exhibit a branched pore geometry producing optical anisotropy and high scattering films.

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Reconfigurable Nanorod Films: An in Situ Study of the Relationship between the Tunable Nanorod Orientation and the Optical Properties of Their Self-Assembled Thin Films

Chemistry of Materials ◽

10.1021/acs.chemmater.5b00503 ◽

2015 ◽

Vol 27 (7) ◽

pp. 2659-2665 ◽

Cited By ~ 9

Author(s):

Christian R. Ocier ◽

Detlef-M. Smilgies ◽

Richard D. Robinson ◽

Tobias Hanrath

Keyword(s):

Thin Films ◽

Optical Properties ◽

In Situ Study ◽

Self Assembled ◽

The Relationship

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In-Situ Diagnostics at High Pressures: Ellipsometric and Rheed Studies of the Growth of Yba2Cu3O7

MRS Proceedings ◽

10.1557/proc-502-237 ◽

1997 ◽

Vol 502 ◽

Cited By ~ 4

Author(s):

Dave H. A. Blank ◽

Horst Rogalla

Keyword(s):

Thin Films ◽

High Pressures ◽

High Vacuum ◽

Pulsed Laser ◽

Complex Oxide ◽

High Energy ◽

Diagnostic Tools ◽

Heteroepitaxial Growth ◽

Deposition Parameters

ABSTRACTPulsed Laser and Sputter Deposition are used for the fabrication of complex oxide thin films at relatively high oxygen pressures (up to 0.5 mBar). This high pressure hampers the application of a number of in-situ diagnostic tools. One of the exceptions is ellipsometry. Using this technique we studied in-situ the growth of off-axis sputtered Yba2Cu3O6+x thin films on (001) SrTiO3 as a function of the deposition parameters. Furthermore, the oxidation process from O(6) to O(7) has been studied by performing spectroscopic ellipsometry during isobaric cooling procedures.Another suitable in-situ monitoring technique for the growth of thin films is Reflection High Energy Electron Diffraction (RHEED). In general this is a (high) vacuum technique. Here, we present an RHEED-system in which we can observe clear diffraction patterns up to a deposition pressure of 0.5 mBar. The system has been used for in-situ monitoring of the heteroepitaxial growth of YBa2Cu3 06+x on SrTiO3 by pulsed laser deposition.

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In situ excimer laser irradiation as cleaning tool for solid phase epitaxy of laser crystallized polycrystalline silicon thin films

physica status solidi (a) ◽

10.1002/pssa.201330056 ◽

2013 ◽

Vol 210 (12) ◽

pp. 2729-2735 ◽

Cited By ~ 1

Author(s):

Ingmar Höger ◽

Thomas Schmidt ◽

Anja Landgraf ◽

Martin Schade ◽

Annett Gawlik ◽

...

Keyword(s):

Thin Films ◽

Laser Irradiation ◽

Excimer Laser ◽

Polycrystalline Silicon ◽

Solid Phase ◽

Solid Phase Epitaxy ◽

Silicon Thin Films ◽

Excimer Laser Irradiation

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Temperature dependence of the transient and AC electrical conductivity of porous silicon thin films

Materials Science and Engineering B ◽

10.1016/s0921-5107(02)00753-5 ◽

2003 ◽

Vol 101 (1-3) ◽

pp. 334-337 ◽

Cited By ~ 4

Author(s):

M. Theodoropoulou ◽

C.A. Krontiras ◽

N. Xanthopoulos ◽

S.N. Georga ◽

M.N. Pisanias ◽

...

Keyword(s):

Thin Films ◽

Electrical Conductivity ◽

Porous Silicon ◽

Temperature Dependence ◽

Ac Electrical Conductivity ◽

Silicon Thin Films

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Luminescent Characteristics of Pulsed Laser Deposited Epitaxial Eu-Doped Y2O3 Films

MRS Proceedings ◽

10.1557/proc-574-11 ◽

1999 ◽

Vol 574 ◽

Author(s):

D. Kumar ◽

K. G. Cho ◽

Zhang Chen ◽

V. Craciun ◽

P. H. Holloway ◽

...

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Epitaxial Growth ◽

Yttrium Oxide ◽

Lattice Mismatch ◽

Pulsed Laser ◽

Laser Deposition ◽

Deposition Technique ◽

Deposition Parameters

AbstractThe growth, structural and cathodoluminescent (CL) properties of europium activated yttrium oxide (Eu:Y2O3) thin films are reported. The Eu:Y2O3 films were grown in-situ using a pulsed laser deposition technique. Our results show that Eu:Y2O3 films can grow epitaxially on (100) LaAlO3 substrates under optimized deposition parameters. The epitaxial growth of Eu:Y2O3 films on LaAlO3, which has a lattice mismatch of ∼ 60 %, is explained by matching of the atom positions in the lattices of the film and the substrate after a rotation. CL data from these films are consistent with highly crystalline Eu:Y2O3 films with an intense CL emission at 611 nm.

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