Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Calculation of the Au-Ge phase diagram for nanoparticles

Eichhammer Y., Roeck J., Moelans N., Iacopi F., Blanpain B., Heyns M.

Archives of Metallurgy and Materials

2008

Vol. 53, iss. 4

1133-1139

The CALPHAD (CALculation of PHAse Diagrams) method provides a powerful tool for the calculation of phase diagrams. It is based on thermodynamic databases gathering information on the relative stabilities of pure substances and mixing properties of alloys. We have added a size dependent contribution to an existing CALPHAD description of the Au-Ge bulk system. The parameters are optimized using composition and temperaturę dependent surface energies calculated according to the Butler model. The effect of particie size on the phase diagram is discussed for spherical nano-particles.

Metoda CALPHAD jest doskonałym narzędziem do obliczania wykresów fazowych na podstawie danych termodynamicznych gromadzonych w różnych bazach danych. W pracy niniejszej dodano czynnik uwzględniający wielkość ziaren materiału do istniejącego opisu temodynamicznego układu Au-Ge. Parametry termodynamiczne zoptymalizowano stosując zależne od składu i temperatury energie powierzchniowe, wyliczone modelem Butlera. Rozpatrzono efekt wpływu rozmiaru cząstek na topologię wykresu fazowego zakładając kulisty kształt cząsteczek.

Evaluation of thin Ta(N) film integrity deposited on porous glasses

Shamiryan D., Baklanov M. R., Yanovitskaya A. V., Zverev A. V., Tőkei Z., Iacopi F., Maex K.

Optica Applicata

2003

Vol. 33, nr 1

91-96

Porous glasses are widely used in microelectronics as inter-metal dielectrics with low dielectric constant (so-called low-k dielectrics). At the same time copper is used as a metal because of its low resistivity. Combination of Cu and low-k requires a barrier to prevent Cu diffusion into a low-k dielectric. Integrity of such a barrier becomes an issue when porous glass is used as a low-k dielectric. The barrier should be as thin as possible and fully dense at the same time. Using solvent (toluene) penetration through a barrier (tantalum nitride in our case, which is non-stoichiometric, hence denoted as Ta(N)) and adsorption in porous glass as a barrier integrity probe, we show that barrier integrity depends not only on porous structure of the glass, but also on its chemical composition (namely on carbon content). Glasses with high carbon content are easier to seal with Ta(N) barrier. With help of Monte Carlo simulations, we speculate that different chemical composition of the porous glass results in different surface diffusion during barrier deposition. Different surface diffusion, in turn, results in different integrity of the porous barrier.