Visible luminescence of nanocrystalline AlN:Er thin film by co-deposition of AlN, Er, and SiO2

Journal of Crystal Growth

Pigeat

2008

a b s t r a c tTo understand the influence of the oxygen on the crystallography of AlN thin films made by physical vapour deposition r.f. magnetron, three different oxygen content AlN films were prepared at room temperature for two values of the energy of the species building the film (low energy obtained by using: low power W, high pressure P; high energy obtained by using: high W, low P). It is observed that the crystalline morphology of the films not only depends on the process parameters (W and P), but is also particularly related to the oxygen content in the films. Regardless of P and W used here, low oxygen content films (5 at%) are columnar. The increase in oxygen content (15-30 at%) reduces the grain size without creating phases like Al 2 O 3 or AlNO, and very rich oxygen films (50 at%) are amorphous. From this study, assumptions are made for the localization of oxygen atoms in the AlN phase.

Section: Discussionmentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

Correlation between the oxygen content and the morphology of AlN films grown by r.f. magnetron sputtering

Journal of Crystal Growth

Pigeat

2008

“…The temperature quenching of the optical centres emission is known to be smaller in wide band gap semiconductors. This is why, AlN, with its theoretical 6,2 eV band gap, is one of the most interesting matrices to study the incorporation of erbium and other rare earths emitting in the whole visible spectrum up to the ultra-violet region [17], [18], [19], [20], [21], [22], [23].…”

Section: Introductionmentioning

confidence: 99%

Erbium location into AlN films as probed by spatial resolution experimental techniques

Boulet

2015

Acta Materialia

This paper presents a thorough experimental investigation of erbium-doped aluminium nitride thin films prepared by R.F. magnetron sputtering, coupling Scanning Transmission Electron Microscopy X-ray-mapping imagery, conventional Transmission Electron Microscopy and X-ray diffraction. The study is an attempt of precise localisation of the rare earth atoms inside the films and in the hexagonal wü rtzite unit cell. The study shows that AlN:Er x is a solid solution even when x reaches 6 at.%, and does not lead to the precipitation of erbium rich phases. The X-ray diffraction measurements completed by simulation show that the main location of erbium in the AlN wü rtzite is the metal substitution site on the whole range. They also show that octahedral and tetrahedral sites of the wü rtzite do welcome Er ions over the [1.6-6%] range. The XRD deductions allow some interpretations on the theoretical mechanisms of the photoluminescence mechanisms and more specifically on their concentration quenching.

“…Among III-V components, aluminum nitride (AlN) semiconductor is interesting thanks to its wide gap (6.2 eV) that has been shown to be useful to reduce the temperature quenching effect induced by free carriers [12][13]. Despite some theoretical works devoted to a structure-related Er 3+ excitation / emission mechanism, the photoluminescence (PL) of rare earth cations inserted in wide gap matrices is still not well understood [14][15]. It is thought that energy transfer between the host matrix and rare earth cations strongly increases the luminescence intensity.…”

Section: Introductionmentioning

confidence: 99%

Structural, chemical and optical characterizations of nanocrystallized AlN:Er thin films prepared by r.f. magnetron sputtering

Materials Science and Engineering: B

Miska

Rinnert

et al. 2008

Nanocrystalline n-AlN:Er thin films were deposited on (001) Silicon substrates by r. f. magnetron sputtering at room temperature to study the correlation between 1.54 μm IR photoluminescence (PL) intensity, AlN crystalline structure and Er concentration rate. This study first presents how Energy-Dispersive Spectroscopy of X-rays (EDSX) Er Cliff Lorimer sensitivity factor = 5 is obtained by combining EDSX and electron probe micro analysis (EPMA) results on reference samples. It secondly presents the relative PL 2 intensities of nanocrystallized samples prepared with identical sputtering parameters as a function of the Er concentration. The structure of crystallites in AlN films is observed by transmission electron microscopy.