Photoluminescence from Gd-implanted AlN and GaN Epilayers

ABSTRACTGaN and AlN thin films were implanted with gadolinium (Gd)atoms and characterized using deep ultra-violet (UV) photoluminescence(PL). The Gd-implanted samples were annealed at temperatures up to 1178K in a flowing N2 gas to facilitate recovery of implantation-related damage. Using the output at 195 nm from a quadrupled Ti:sapphire laser, narrow PL emission was observed at 318 nm from the Gd- implanted AlN thin films. This emission is characteristic of the lowest energy 4f transition of the trivalent Gd ion. A boarder emission band, also centered at 318 nm, was observed under excitation at 266 nm. No PL emission was observed from the Gd-implanted GaN thin films at either the bandedge or due to a 4f transition. The dependence of the UV emission on AlN sample temperature was systematically studied. The peak PL emission intensity decreased by less that a factor of 3 over the temperature range of 10 K to 300 K. Decay transients of the UV emission were measured indicating that the lifetime of this emission is very fast.

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Role of Al in engineering the optical band gap and PL emission intensity properties of CdO thin films grown by SILAR method

Optical Materials ◽

10.1016/j.optmat.2021.111921 ◽

2022 ◽

Vol 123 ◽

pp. 111921

Author(s):

Harun Güney ◽

Demet İskenderoğlu ◽

Muhammed Emin Güldüren ◽

Sibel Morkoç Karadeniz

Keyword(s):

Thin Films ◽

Band Gap ◽

Emission Intensity ◽

Optical Band Gap ◽

Silar Method ◽

Pl Emission ◽

Cdo Thin Films

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The Origin of Luminescence From Cerium Oxide on Silicon

MRS Proceedings ◽

10.1557/proc-560-227 ◽

1999 ◽

Vol 560 ◽

Author(s):

Won Chel Choiv ◽

Ho Nyung Lee ◽

Yong Kim ◽

Eun Kyu Kim

Keyword(s):

Thin Films ◽

Thermal Treatment ◽

Cerium Oxide ◽

Cerium Dioxide ◽

Room Temperature ◽

Ultra Violet ◽

Blue Luminescence ◽

Luminescent Material ◽

Uv Emission ◽

Thermally Treated

ABSTRACTAs the ultra-violet/blue luminescent material, we will introduce the thermal treated cerium oxide on silicon. It has been confirmed a violet/blue luminescence ranging from 358 rim to 450 rnm at room temperature from the thermally treated cerium-dioxide thin films on silicon. As a results of AES and HR-TEM measurement, it was confirmed that cerium silicates were generated by thermal treatment. These cerium silicates such as Ce4.667(SiO4)3O and Ce2Si2O7 are the source of the ultra-violet (UV) emission ranging from 358 nim to 450 nm (maximum at 388 rim).

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Optical investigations on sputtered CuCl thin films

MRS Proceedings ◽

10.1557/proc-0891-ee03-22 ◽

2005 ◽

Vol 891 ◽

Cited By ~ 1

Author(s):

Gomathi Natarajan ◽

Anirban Mitra ◽

Lisa O'Reilly ◽

Stephen Daniels ◽

David C. Cameron ◽

...

Keyword(s):

Thin Films ◽

Room Temperature ◽

Free Exciton ◽

Ultra Violet ◽

Rf Magnetron Sputtering ◽

Potential Candidate ◽

X Ray Diffraction ◽

Optical Absorbance ◽

Uv Emission ◽

Silicon Device

ABSTRACTCopper (I) chloride (CuCl) is a potential candidate for ultra violet optoelectronics due to the fact that it is closely lattice matched with silicon, which makes it readily integrable with silicon device technology. The structural and optoelectronic properties of CuCl thin films deposited by RF magnetron sputtering are investigated. The crystallinity is studied using X-ray diffraction which confirms the growth of CuCl thin films with cubic zinc blende structure predominantly orientated in <111> direction. Excitonic transitions in the thin films were thoroughly investigated using optical absorbance and luminescence spectroscopies. Room temperature absorption spectroscopic analysis confirms the existence of two exciton peaks namely Z12 and Z3 at 372 and 380 nm respectively. A strong UV emission is observed at room temperature in cathodoluminescence and photoluminescence spectra due to the recombination of Z3 exciton at approximately 384 nm. In the low temperature photoluminescence spectrum, a free exciton (Z3) and a bound exciton (I1) are observed. A variation of 1.3 nm to 10 nm was observed in the Z3 exciton line width from 10 K to 300 K.

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Study of C2H5O2 using modulated photolysis: ultra-violet spectrum and self-reaction kinetics in the temperature range 233-363 K

Journal de Chimie Physique ◽

10.1051/jcp/1997940484 ◽

1997 ◽

Vol 94 ◽

pp. 484-502

Author(s):

S Fauvet ◽

JP Ganne ◽

J Brion ◽

D Daumont ◽

J Malicet ◽

...

Keyword(s):

Reaction Kinetics ◽

Ultra Violet ◽

Temperature Range

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Stabilization of Ferroelectric Phase in Highly Oriented Quinuclidinium Perrhenate (HQReO4) Thin Films

Materials ◽

10.3390/ma14092126 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2126

Author(s):

Junyoung Lee ◽

Woojun Seol ◽

Gopinathan Anoop ◽

Shibnath Samanta ◽

Sanjith Unithrattil ◽

...

Keyword(s):

Thin Films ◽

Solution Process ◽

Intermediate Temperature ◽

Perovskite Oxide ◽

Temperature Phase ◽

Polar Phase ◽

Practical Applications ◽

Temperature Range ◽

Potential Alternative ◽

Temperature Window

The low-temperature processability of molecular ferroelectric (FE) crystals makes them a potential alternative for perovskite oxide-based ferroelectric thin films. Quinuclidinium perrhenate (HQReO4) is one such molecular FE crystal that exhibits ferroelectricity when crystallized in an intermediate temperature phase (ITP). However, bulk HQReO4 crystals exhibit ferroelectricity only for a narrow temperature window (22 K), above and below which the polar phase transforms to a non-FE phase. The FE phase or ITP of HQReO4 should be stabilized in a much wider temperature range for practical applications. Here, to stabilize the FE phase (ITP) in a wider temperature range, highly oriented thin films of HQReO4 were prepared using a simple solution process. A slow evaporation method was adapted for drying the HQReO4 thin films to control the morphology and the temperature window. The temperature window of the intermediate temperature FE phase was successfully widened up to 35 K by merely varying the film drying temperature between 333 and 353 K. The strategy of stabilizing the FE phase in a wider temperature range can be adapted to other molecular FE materials to realize flexible electronic devices.

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