000			02845cam a2200349 a 4500
003			EG-GiCUC
005			20250223031102.0
008			141102s2013 ua dh f m 000 0 eng d
040			_aEG-GiCUC _beng _cEG-GiCUC
041	0		_aeng
049			_aDeposite
097			_aPh.D
099			_aCai01.24.12.Ph.D.2013.Sa.S
100	0		_aSamah Mohamed Hamdy Ahmed
245	1	0	_aSpectroscopic study of Eu-doped nano semiconductors prepared by laser ablation or RF sputtering / _cSamah Mohamed Hamdy Ahmed ; Supervised Mostafa Elsayed , Lotfia Elnadi , Yahia Badr
246	1	5	_aدراسة طيفية لاشتباه الموصلات النانومترية والمشابة باليورابيوم والمحضرة بطريقة الليزر الاقتلاعى أو التطاير بواسطة موجات الراديو
260			_aCairo : _bSamah Mohamed Hamdy Ahmed , _c2013
300			_a170 P. : _bcharts , facsimiles ; _c25cm
502			_aThesis (Ph.D.) - Cairo University - National Institute of Laser Enhanced Sciences - Department of Laser Science and Interaction
520			_aRare-earth-doped wide-bandgap semiconductors are an interesting class of inorganic luminescent materials with complex optical properties and widespread potential applications in optoelectronics. Undoped and Eu-doped GaN powders have been synthesized by the co-precipitation method followed by nitridation at high temperature. The X-ray diffraction (XRD) patterns reveal the single-phase wurtzite structure of the synthesized undoped and Eu-doped GaN powders. The morphology of the samples was examined by the field emission scanning electron microscope (FE-SEM) and the high resolution transmission electron microscope (HR-TEM), and it was shown that the micron-sized particles are composed of agglomerated nano-crystallites. This agglomeration may be due to the absence of any surfactant during the preparation. Under above bandgap excitation, the room-temperature photoluminescence (PL) of both samples show the characteristic GaN band-edge emission peak at 363 nm, as well as a broad defect-related emission band centered at around 415 nm. The Eu-doped GaN sample, under below bandgap excitation at 464 nm, exhibited red emission peaks at 593 nm and 616 nm, corresponding to the ⁵D₀ {u2192} ⁷F₁ and ⁵D₀ {u2192} ⁷F₂ transitions, respectively, within the 4f-shell of Eu³⁺ ions ions
530			_aIssued also as CD
653		4	_aRare-earth ions
653		4	_aSemiconductors
653		4	_aZinc oxide
700	0		_aLotfia Elnadi , _eSupervisor
700	0		_aMostafa Elsayed , _eSupervisor
700	0		_aYahia Badr , _eSupervisor
856			_uhttp://172.23.153.220/th.pdf
905			_aAml _eCataloger
905			_aNazla _eRevisor
942			_2ddc _cTH
999			_c48088 _d48088