Light emission and atomic coordination structure of sol-gel derived erbium-doped SiO 2 -TiO 2 thin films

A series of Zn1− x Mg x O thin films with the composition range x = 0.00–0.40 has been prepared by sol–gel spin coating on Si substrates with a post-deposition thermal treatment in the temperature range of 400–650 °C. The morphology of the films was investigated by scanning electron microscopy and atomic force microscopy while their light emission properties were studied by photoluminescence spectroscopy under excitation at 325 nm. It was found that annealing at 500 °C leads to the production of macroscopically homogeneous wurtzite phase films, while thermal treatment at higher or lower temperature results in the degradation of the morphology, or in the formation of ZnO particles embedded into the ZnMgO matrix, respectively. Local compositional fluctuations leading to the formation of deep band tails in the gap were deduced from photoluminescence spectra. A model for the band tail distribution in the bandgap is proposed as a function of the alloy composition. Thin films were also prepared by aerosol spray pyrolysis deposition using the same sol–gel precursors for the purpose of comparison. The prepared films were tested for photodetector applications.

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EXAFS studies on erbium-doped TiO2 and ZrO2 sol–gel thin films

Journal of Non-Crystalline Solids ◽

10.1016/s0022-3093(01)00805-5 ◽

2001 ◽

Vol 291 (1-2) ◽

pp. 56-77 ◽

Cited By ~ 23

Author(s):

C. Mignotte

Keyword(s):

Thin Films ◽

Sol Gel ◽

Doped Tio2 ◽

Erbium Doped ◽

Zro2 Sol

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Investigation on the Dielectric and Polarization Behavior of Sol-Gel Derived Erbium Doped Pb(Zr 0.53 Ti 0.47 )O 3 Thin Films

Integrated Ferroelectrics ◽

10.1080/10584580210861 ◽

2002 ◽

Vol 42 (1) ◽

pp. 373-384 ◽

Cited By ~ 7

Author(s):

B. Roy ◽

S. B. Majumder ◽

R. S. Katiyar

Keyword(s):

Thin Films ◽

Sol Gel ◽

Polarization Behavior ◽

Erbium Doped

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Rare-earth doped microlasers for microphotonic applications

MRS Proceedings ◽

10.1557/proc-817-l1.6 ◽

2004 ◽

Vol 817 ◽

Author(s):

Lan Yang ◽

Bumki Min ◽

K. J. Vahala

Keyword(s):

Thin Films ◽

Continuous Wave ◽

Sol Gel ◽

Single Mode ◽

Optical Quality ◽

Optical Fiber Communications ◽

High Q ◽

Optical Microresonators ◽

Surface Optical ◽

Erbium Doped

AbstractSol gels provide a highly flexible technique for preparation of both planar and non-planar oxide thin films. They also enable the incorporation of various dopants into the films. In this work we describe the application of erbium-doped solgel films to surface functionalize optical microresonators. The resulting microlaser devices are especially interesting because their emission band falls in the important 1.5 μm window used for optical fiber communications. Both microsphere and ultra-high-Q microtoroid resonators-on-a-chip were functionalized into lasers and then characterized [1]. The erbium-doped sol-gel films were applied to the resonator surface and subsequently a CO2 laser was used to induce flow and densification of the sol-gel film on the surface. Optical quality thin films were obtained after the CO2 laser induced anneal. By varying the doping concentration and thickness of the applied sol-gel layers in microsphere resonators, we can vary the laser dynamics so that both continuous-wave and pulsation operation are possible. Single mode performance with high differential quantum efficiency was also obtained using the ultra-high-Q microtoroid resonator. These chip-based microlasers enable integration with other optical or electronic functions [2-3].

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The crystallization of thin-film ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122095 ◽

1992 ◽

Vol 50 (1) ◽

pp. 338-339

Author(s):

J.M. Schwartz ◽

L.F. Francis ◽

L.D. Schmidt ◽

P.S. Schabes-Retchkiman

Keyword(s):

Thin Films ◽

Grain Size ◽

Sol Gel ◽

Processing Route ◽

Small Areas ◽

Ceramic Thin Films ◽

Complex Shapes ◽

Sol Gel Process ◽

Ceramic Precursors ◽

Crystalline Ceramic

Ceramic thin films and coatings are of interest for electrical, optical, magnetic and thermal barrier applications. Critical for improved properties in thin films is the development of specific microstructures during processing. To this end, the sol-gel method is advantageous as a versatile processing route. The sol-gel process involves depositing a solution containing metalorganic or colloidal ceramic precursors onto a substrate and heating the deposited layer to form a crystalline or non-crystalline ceramic coating. This route has several advantages, including the ability to create tailored microstructures and properties, to coat large or small areas, simple or complex shapes, and to more easily prepare multicomponent ceramics. Sol-gel derived coatings are amorphous in the as-deposited state and develop their crystalline structure and microstructure during heat-treatment. We are particularly interested in studying the amorphous to crystalline transformation, because many key features of the microstructure such as grain size and grain size distribution may be linked to this transformation.

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