Mechanism of Oxygen Redistribution During Ultra-shallow Junction Formation in Silicon

The transport of dissolved oxygen in the Czochralski silicon towards the arsenic-doped ultra-shallow junction was investigated. Ultra-shallow junction was formed by low-energy As+ ion implantation with the subsequent furnace annealing at 750 C-950 C temperatures for the dopant activation. Oxygen and arse-nic redistributions were investigated by secondary ion mass spectrometry (SIMS) technique. The peculiari-ties of defect creation and transformation were studied by the X-ray diffuse scattering technique (XDS). It was found that oxygen concentration in the arsenic redistribution region is increased a few times already after 1 minute of annealing. Increase of annealing time leads to decrease of oxygen accumulation as a re-sult of oxygen transportation to the SiO2/Si interface. As a result the thickness of screen silicon oxide is in-creased by 0.5 nm. This effect is related with the oxygen gettering from the wafer bulk. A physical mecha-nism of the oxygen transfer is discussed. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3527

Formation of silicon nanoclusters in buried ultra-thin oxide layers

The peculiarities of buried layer formation obtained by co-implantation of O2 ions with the energy of 130 keV and carbon ions within the energy range of 30-50 keV have been investigated. The corresponding ion doses for carbon and oxygen ions were equal to 2 x 10¹⁶ cm⁻² and 1.8 x 10¹⁷ cm⁻², respectively. It has been observed that annealing at 1150 °C results in enhanced oxygen diffusion towards the region with a maximum carbon concentration. Analysis of X-ray diffraction patterns with a SIMS depth profiles inherent to annealed samples suggests formation of Si nanoclusters in the region with maximum concentrations of carbon and oxygen vacancies. The intensive luminescence has been observed with the maximum at 600 nm, which could be associated with silicon nano-inclusions in thin stoichiometric SiO₂ layer

Strain relaxation in thin Si₁-ₓ-yGeₓCy layers on Si substrates

The possibility to obtain a heterosystem consisting of the upper partially strained and lower relaxed layers by gradient in situ doping of SiGe layers with carbon is considered. The properties of the as-grown and annealed (600 to 1000℃) samples have been studied by Raman spectroscopy and atomic force microscopy. The strain relaxation degree in the as-grown layers as estimated from the Raman spectra amounts 50 % for Si₀.₇-ʸGe₀.₃Сʸ and 0 % for Si₀.₉-ʸGe₀.₁Сʸ. During the annealing, the strain has been found to be relaxed not homogeneously over the whole structure but in a layer-by-layer way. The segregation of carbon atoms is observed for both types of as-grown Si₁-ₓ-ʸGeₓСʸ layers in the near-substrate regions.Розглянуто можливiсть отримання вiдрелаксованих sige шарiв на кремнiєвiй пiдкладцi, що градiєнтно in situ легувалися вуглецем у процесi епiтаксiї. Використовуючи спектроскопiю комбiнацiйного розсiювання свiтла (КРС) та атомну силову мiкроскопiю, дослiджено властивостi вихiдних зразкiв та зразкiв пiсля термiчних обробок у дiапазонi температур 600-1000℃. Iз спектрiв КРС оцiнено ступiнь пластичної релаксацiї у вихiдному Si₀.₇-ʸGe₀.₃Сʸ (50 %) та Si₀.₉-yGe₀.₁Сʸ (0 %) шарах. Встановлено, що при вiдпалах релаксацiя напружень вiдбувається не однаково по всьому об'єму, а пошарово. В обох типах Si₁-ₓ-ʸGeₓСʸ шарiв на їх iнтерфейсах з Si пiдкладками вiдбувається сегрегацiя вуглецю.Рассмотрена возможность получения отрелаксированных sige слоев на кремниевой подложке, градиентно in situ легированных углеродом в процессе эпитаксии. Используя спектроскопию комбинационного рассеяния света (КРС) и атомную силовую микроскопию, исследованы свойства исходных образцов и образцов после термических обработок в диапазоне температур 600-1000℃. Из спектров КРС оценена степень пластической релаксации в исходном Si₀.₇-ʸGe₀.₃Сʸ (50 %) и Si₀.₉-ʸGe₀.₁Сʸ (0 %) слоях. Установлено, что релаксация напряжений при отжигах происходит не однородно по всему объему, а послойно. В обоих типах Si₁-ₓ-ʸGeₓСʸ слоев происходит сегрегация углерода на интерфейсах с Si подложками