Optical properties of Y2O3 thin films doped with spatially controlled Er3+ by atomic layer deposition

Abstract

Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers)Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. We report in this work the optical properties of Er 3+ -doped Y 2 O 3 , deposited by radical enhanced atomic layer deposition. Specifically, the 1.53 m absorption cross section of Er 3+ in Y 2 O 3 was measured by cavity ring-down spectroscopy to be ͑1.9± 0.5͒ ϫ 10 −20 cm 2 , about two times that for Er 3+ in SiO 2 . This is consistent with the larger Er 3+ effective absorption cross section at 488 nm, determined based on the 1.53 m photoluminescence yield as a function of the pump power. X-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy were used to determine the film composition, which in turn was used to analyze the extended x-ray absorption fine structure data, showing that Er was locally coordinated to only O in the first shell and its second shell was a mixture of Y and Er. These results demonstrated that the optical properties of Er 3+ -doped Y 2 O 3 are enhanced, likely due to the fully oxygen coordinated, spatially controlled, and uniformly distributed Er 3+ dopants in the host. These findings are likely universal in rare-earth doped oxide materials, making it possible to design materials with improved optical properties for their use in optoelectronic devices.

Er3+ and Si luminescence of atomic layer deposited Er-doped Al2O3 thin films on Si(100)

“…Other impurities, such as CH x , can also be identified as possible quenching centers. The stretching vibration of CH 3 is located in the infrared absorption spectrum at an energy of $2945 cm À1 , 27,33 which is in the same energy range as that of OH. The removal of hydrogen from the films during annealing may explain the negative correlation between the Er 3þ and Si photoluminescence.…”

“…[4][5][6][7] Nonetheless, in photovoltaics, technology based on UC processes to harvest sub-bandgap photons has not yet advanced to the point where such devices are practical. Fundamental issues, such as the typically small absorption cross-section of Er ($10 À20 cm À2 ) 27,49,50 and the strong dependence of the UC efficiency on the light intensity, 4,13,39 complicate a straightforward solution based on UC for significantly increasing Si solar cell efficiencies.…”

“…In addition, ALD has been used for Er incorporation in Y 2 O 3 by alternating the growth of Y 2 O 3 and Er 2 O 3 layers. 17,27 In this study, we used thermal ALD to synthesize amorphous Al 2 O 3 :Er films on Si wafers. The focus of the paper is the relation between the (structural) changes of the material during annealing and the optical activation of Er 3þ .…”

Plasma-Assisted Atomic Layer Deposition: Basics, Opportunities, and Challenges

“…A classic example is the ALD of metal oxides from b-diketonate precursors, such as those with acac (acetylacetonate), [97][98][99][100] hfac (1,1,1,5,5,5-hexafluoroacetylacetonate), 101,161,162 and thd (2,2,6,6,-tetramethyl-3,5-heptanedionato) 102,104,[275][276][277][278][279] ligands. Such precursors require more reactive co-reactants as they show no or low reactivity with H 2 O (in essence, they do not readily undergo hydrolysis reactions).…”

Preparation and Optical Properties of YH2:Er2+ and Y2O3:Er3+ Nanoparticles

“…18 On the other hand, the Y 2 O 3 :Er 3+ film was also prepared by the radical enhanced atomic layer deposition method. 19 The peaks of the PL spectra of Y 2 O 3 :Er 3+ thin film between the wavelength of 1400 and 1600 nm were not sharp enough, and the full width at half maximum was about 8 nm. It is well-known that the particle size and morphology affect the optical properties greatly, and the particles in nanoscale often exhibit specific properties.…”