Multimodal impurity redistribution and nanocluster formation in Ge implanted silicon dioxide films

Borany, J. von; Grötzschel, R.; Heinig, Karl-Heinz; Markwitz, A.; Matz, W.; Schmidt, Bernd; Skorupa, W.

doi:10.1063/1.120294

Cited by 104 publications

(59 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For these films a narrow band of Ge nanocrystals was found close ͑ϳ10 nm͒ to the Si/SiO 2 interface. 19 In the present experiments, the typical Si diffusion distance at 1100°C, 10 min is a few nm, 14 so that strong effects on the nucleation kinetics can indeed be expected close to the two interfaces. In this way surfaces and interfaces may be used in the future to fit size distributions of Si nanocrystals in SiO 2 .…”

Section: B Depth Distribution Of Luminescent Si Nanocrystalsmentioning

confidence: 87%

Depth distribution of luminescent Si nanocrystals in Si implanted SiO2 films on Si

Brongersma

Polman

Min

et al. 1999

Journal of Applied Physics

View full text Add to dashboard Cite

Depth-resolved measurements of the photoluminescence of Si implanted and annealed SiO 2 films on Si have been performed to determine the depth distribution of luminescent Si nanocrystals. Si nanocrystals with diameters ranging from ϳ2 to 5 nm were formed by implantation of 35 keV Si ions into a 110-nm-thick thermally grown SiO 2 film on Si͑100͒ at a fluence of 6ϫ10 16 Si/cm 2 , followed by a thermal anneal at 1100°C for 10 min. The photoluminescence spectrum is broad, peaks at ϭ790 nm, and contains contributions from both recombination of quantum confined excitons in the nanocrystals and ion-implantation-induced defects. By chemical etching through the SiO 2 film in steps and analyzing the changes in the photoluminescence spectrum after each etch step, the depth from which each of the two luminescence features originate is determined. The etch rate of the oxide, as derived from Rutherford backscattering spectrometry data, varies from 1.3 nm/s in the regions of small excess Si to 0.6 nm/s at the peak of the concentration profile ͑15 at. % excess Si͒. It is found that the defect luminescence originates from an ϳ15-nm-thick near-surface region. Large nanocrystals luminescing at long wavelengths ͑ ϭ900 nm͒ are mainly located in the center of the film, where the Si concentration is highest ͑48 at. %͒. This is corroborated by transmission electron microscopy that shows a high density of Si nanocrystals in the size range of 2-5 nm in the center of the film. The largest density of small luminescent nanocrystals ͑ ϭ700 nm͒, not detectable by electron microscopy is found near the SiO 2 surface and the SiO 2 /Si interface. This is attributed to either the fact that the surface and the SiO 2 /Si interface affect the Si nanocrystal nucleation kinetics in such a way that small nanocrystals are preferentially formed in these regions, or an optical interaction between nanocrystals of different sizes that quenches the luminescence of small nanocrystals in the center of the film.

show abstract

Section: B Depth Distribution Of Luminescent Si Nanocrystalsmentioning

confidence: 87%

Depth distribution of luminescent Si nanocrystals in Si implanted SiO2 films on Si

Brongersma

Polman

Min

et al. 1999

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…21,22 Here, growth is performed well above the melting point of the Ge nanocrystals so that Ge clusters grow as molten nanodroplets that solidify in sapphire upon rapid cooling. Because solid Ge has a lower density than liquid Ge, the resulting solid nanoparticles are larger than the sapphire matrix cavities and they are under compressive stress.…”

Section: Raman Spectroscopymentioning

confidence: 99%

Structural properties of Ge nanocrystals embedded in sapphire

Sharp

et al. 2006

Journal of Applied Physics

View full text Add to dashboard Cite

Isotopically pure 74 Ge nanocrystals were formed in a sapphire matrix by the ion beam synthesis method. In contrast to those embedded in amorphous silica, sapphire-embedded nanocrystals are clearly faceted and are preferentially oriented with respect to the crystalline matrix. In situ transmission electron microscopy of heated samples reveals that the nanocrystals melt at 955 °C ± 15 °C, very near to the bulk Ge melting point. Raman spectra indicate that the sapphireembedded Ge nanocrystals are under compressive stress in the range of 3 -4 GPa. The 2 magnitude of the stress is consistent with that expected for hydrostatic pressure arising from solidification. Stress relaxation was not observed for sapphire-embedded Ge nanocrystals; this is attributed to the slow self-diffusion rate of the alumina matrix atoms at temperatures below the nanocrystal melting point.

show abstract

“…где r -радиус, r 0 -критический радиус нано-кристалла, D -коэффициент диффузии Ge в SiO 2 , C p = 4.5 · 10 22 cм −3 -плотность атомов германия в нанокристалле Ge, C ′ = 10 18 cм −3 -концентрация ато-мов Ge на границе раздела между нанокристаллом германия и окружающей матрицей (равна пределу рав-новесной растворимости Ge в SiO 2 ) [8], C 0 -концен-трация атомов германия в матрице SiO 2 (концентрация имплантированных атомов Ge), t -время. Для того что-бы оценить критический радиус нанокристалла Ge, мы использовали значения, соответствующие пересыщению пленки SiO 2 атомами германия 3 ат% после отжига при Рис.…”

Section: результаты и обсуждениеunclassified

“…• С способен диффундировать из имплантированного слоя SiO 2 к границе раздела Si/SiO 2 [8,9]. Это означает, что зарож- [9,10].…”

Section: Introductionunclassified

Диффузионно-контролируемый рост нанокристаллов Ge в пленках SiO-=SUB=-2-=/SUB=- в условиях ионного синтеза под высоким давлением

Tyschenko¹,

Черков²

2017

Физика И Техника Полупроводников

View full text Add to dashboard Cite

Изучен рост нанокристаллов германия в пленках SiO2 в зависимости от дозы имплантированных ионов Ge+ и температуры отжига под давлением 12 кбар. Установлено, что зависимость размеров нанокристаллов от концентрации атомов германия и от времени отжига описывается соответствующими корневыми функциями. Квадрат радиуса нанокристалла является экспоненциальной функцией обратной температуры. Полученные зависимости соответствуют модели диффузионно-контролируемого механизма роста нанокристаллов. По температурной зависимости размеров нанокристаллов определен коэффициент диффузии германия в SiO2 под давлением 12 кбар: D=1.1·10-10exp(-1.43/kT). Увеличение коэффициента диффузии Ge под давлением объяснено изменением активационного объема образования и миграции точечных дефектов. Получены данные в пользу межузельного механизма диффузии атомов германия к зародышам нанокристаллов в SiO2. DOI: 10.21883/FTP.2017.10.45023.8564

show abstract

Multimodal impurity redistribution and nanocluster formation in Ge implanted silicon dioxide films

Cited by 104 publications

References 18 publications

Depth distribution of luminescent Si nanocrystals in Si implanted SiO2 films on Si

Depth distribution of luminescent Si nanocrystals in Si implanted SiO2 films on Si

Structural properties of Ge nanocrystals embedded in sapphire

Диффузионно-контролируемый рост нанокристаллов Ge в пленках SiO-=SUB=-2-=/SUB=- в условиях ионного синтеза под высоким давлением

Contact Info

Product

Resources

About