The reactive growth of tantalum silicides was studied by means of Ta-Si diffusion couples annealed at 1250-1350 degreesC for 2-36 h. Two layers, corresponding to Ta5Si3 and TaSi2, were observed in the diffusion zone. The TaSi2 layer was about 1 order of magnitude thicker than the Ta5Si3 layer. Formation of the compounds Ta3Si and Ta2Si was not detected. probably because their growth rate is very small. The concept of rate constant of the second kind was used to describe the growth kinetics of the silicides. For Ta5Si3, different values of the rate constant of the second kind can be obtained depending on the boundary conditions adopted at the Ta/Ta5Si3 interface. The rate constant of the second kind was related to diffusion properties and thermodynamic stability of the given phase. Average values of the interdiffusion coefficient were calculated for the Ta5Si3 and TaSi2 Compounds. The corresponding activation energy is similar to450 kJ mol(-1) for Ta5Si3 and similar to560 kJ mol(-1) for TaSi2.

Reactive growth of tantalum silicides in Ta-Si diffusion couples

Buscaglia V;
2002

Abstract

The reactive growth of tantalum silicides was studied by means of Ta-Si diffusion couples annealed at 1250-1350 degreesC for 2-36 h. Two layers, corresponding to Ta5Si3 and TaSi2, were observed in the diffusion zone. The TaSi2 layer was about 1 order of magnitude thicker than the Ta5Si3 layer. Formation of the compounds Ta3Si and Ta2Si was not detected. probably because their growth rate is very small. The concept of rate constant of the second kind was used to describe the growth kinetics of the silicides. For Ta5Si3, different values of the rate constant of the second kind can be obtained depending on the boundary conditions adopted at the Ta/Ta5Si3 interface. The rate constant of the second kind was related to diffusion properties and thermodynamic stability of the given phase. Average values of the interdiffusion coefficient were calculated for the Ta5Si3 and TaSi2 Compounds. The corresponding activation energy is similar to450 kJ mol(-1) for Ta5Si3 and similar to560 kJ mol(-1) for TaSi2.
2002
Istituto di Chimica della Materia Condensata e di Tecnologie per l'Energia - ICMATE
Istituto di Chimica della Materia Condensata e di Tecnologie per l'Energia - ICMATE
File in questo prodotto:
File Dimensione Formato  
prod_21610-doc_56110.pdf

non disponibili

Descrizione: Reactive growth of tantalum silicides in Ta-Si diffusion couples
Dimensione 72.15 kB
Formato Adobe PDF
72.15 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14243/433656
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 20
  • ???jsp.display-item.citation.isi??? 19
social impact