CVD-MONITORING: Improved CVD process control by in-situ spectroscopic monitoring

• Research unit: EU RFP
• Project number: 97.0564

Key words (English)

CVD; FTIR; ceramic fibres; gas phase reaction; high temperature

Alternative project number (English)

EU project number: BRPR-CT96-0322

Research programs (English)

EU-programme: 4. Frame Research Programme - 2.1 Industrial and materials technologies

Short description (English)

See abstract

Further information (English)

Full name of research-institution/enterprise:
Eidg. Materialprüfungs- und Forschungsanstalt EMPA
Hochleistungskeramik

Partners and International Organizations (English)

Coordinator: Fraunhofer Institut (D)

Abstract (English)

EMPA Dübendorf has performed extensive investigations on a CVD process for growing amorphous Si-N-O ceramic fibres. This fibre reveals an excellent high temperature stability in chemical, structural and mechanical aspects. The long-range goal of this work was upscaling of the lab-scale process to pilot-scale production quantities and achievement of process control via intrared spectorscopy.
Production scale-up has been attained by construction of a prototype reactor (Swiss patent 1817/99) with an increased fibre growth area. To control the processing condition, analysis of the gas phase during fibre growth at 1450° has been performed by in-situ infrared spectroscopy. For performance of fundamental studies, the infrared device has been installed first at a lab-scale reactor. In an advanced stage the spectrometer has been transferred to the prototype reactor, thereby allowing comparison of the gas phase spectra analysed in the lab-scale and the pilot reactor. All gas species such as predicted by the fibre growth model could be detected in both reactors, especially SiO.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 97.0564