Chemischer Transport intermetallischer Phasen III: Das System Co-Si / Chemical Vapour Transport of Intermetallic Phases III: The System Co -Si

Abstract

Chemical Vapour Transport, Calculation of CTR, Thermodynamic Data Five phases exist in the system Co-Si: Co3Si, aand /?-Co2Si, CoSi and CoSi2. The phases a-Co2Si and CoSi could be prepared by chemical transport with iodine as transport agent in the temperature range between Ti (700 °C) and T2 (900 °C). In a attempted systematic clarification of the chemical transport reactions of all phases in the system, the effective transport equilibria were determined. Thermodynamic data show satisfactory agreement bet ween calculation and experiment.

Chemical Vapor Transport Reactions – A Historical Review

“…Especially components containing an element of group 14 have been studied in detail. [58,59,60] Since even binary systems may contain many phases, predicting the transport behavior (transport direction, enrichment or depletion of one component in the deposited solid) requires detailed thermodynamic information and application of advanced models (see Section 8).…”

Absolute Structure from Scanning Electron Microscopy

“…Single crystal preparation. Single crystals of CoSi were grown via chemical transport reaction using iodine as a transport agent 34,35 . In a first step, CoSi was synthesized by isothermal reaction of the elements cobalt (powder Alfa Aesar 99.998%) and silicon (powder Alfa Aesar 99.999%) in the presence of iodine (Alfa Aesar 99.998%) at 700 °C in evacuated fused silica tubes during 120 h. In a second step, CoSi was recrystallized during 3 weeks by a chemical transport reaction in a temperature gradient from 700 °C (source) to 800 °C (sink), and a transport agent concentration of 0.5 mg/cm 3 iodine (Alfa Aesar 99.998%).…”