Publikations Einzelansicht

Titel: Processes for new Materials: Deposition of Ceramic Phases by CVD and PVD
 

Autor(en):
 
D. Neuschütz und A. von Richthofen
 
Journal: The Sefström Symposium
Jahr: 1994
Seite(n): 117-130


Zusammenfassung:
Introduction<br>Processes for new materials is a pretentious title promising new products and new processes where most frequently materials with improved properties and intelligently adapted processes are actually meant. Steelmakers claim that all of their steel qualities used in automotive production today are new developments of the last 20 years – new materials, then. Composite materials are often quoted to be typical new materials, but is the tinplated can a new material, not to speak of glazed pottery? Vapor deposition processes (CVD and PVD) have the touch of being new and innovative. Again, the first concepts for depositing pyrocarbon from gaseous hydrocarbons are over 100 years old.<br> Even the technical production and application of metastable phases which is very much looked into presently is nothing really new: Materials technologists are long familiar with the glassy state, and, in metallurgy, with metastable cementite in iron-carbon alloys. Therefore, the non-equilibrium state is not at all a new discovery, although process developments like Physical Vapor Deposition have admittedly extended our possibilities to produce technically useful metastable materials.<br> The following examples taken from recent work of my laboratory are to illustrate two different cases of non-equilibrium in the production of ceramic materials by vapor phase deposition: Case 1 is the deposition of silicon carbide by CVD, a production process showing striking deviations from the calculated gas-solid equilibria. Case 2 deals with the deposition of aluminium oxynitride phases via PVD at low temperatures leading to metastable single-phase Al-O-N.<br> The processes summarized under the headings Chemical and Physical Vapor Deposition cannot any more be distinguished by means of the terms 'chemical' and 'physical'. Plasma Enhanced CVD and Reactive PVD are examples of process modifications with overlapping features. Presently, CVD and PVD processes are distinguished through their respective operating pressures.

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Publikations Einzelansicht

Titel: Processes for new Materials: Deposition of Ceramic Phases by CVD and PVD
 

Autor(en):
 
D. Neuschütz und A. von Richthofen
 
Journal: The Sefström Symposium
Jahr: 1994
Seite(n): 117-130


Zusammenfassung:
Introduction<br>Processes for new materials is a pretentious title promising new products and new processes where most frequently materials with improved properties and intelligently adapted processes are actually meant. Steelmakers claim that all of their steel qualities used in automotive production today are new developments of the last 20 years – new materials, then. Composite materials are often quoted to be typical new materials, but is the tinplated can a new material, not to speak of glazed pottery? Vapor deposition processes (CVD and PVD) have the touch of being new and innovative. Again, the first concepts for depositing pyrocarbon from gaseous hydrocarbons are over 100 years old.<br> Even the technical production and application of metastable phases which is very much looked into presently is nothing really new: Materials technologists are long familiar with the glassy state, and, in metallurgy, with metastable cementite in iron-carbon alloys. Therefore, the non-equilibrium state is not at all a new discovery, although process developments like Physical Vapor Deposition have admittedly extended our possibilities to produce technically useful metastable materials.<br> The following examples taken from recent work of my laboratory are to illustrate two different cases of non-equilibrium in the production of ceramic materials by vapor phase deposition: Case 1 is the deposition of silicon carbide by CVD, a production process showing striking deviations from the calculated gas-solid equilibria. Case 2 deals with the deposition of aluminium oxynitride phases via PVD at low temperatures leading to metastable single-phase Al-O-N.<br> The processes summarized under the headings Chemical and Physical Vapor Deposition cannot any more be distinguished by means of the terms 'chemical' and 'physical'. Plasma Enhanced CVD and Reactive PVD are examples of process modifications with overlapping features. Presently, CVD and PVD processes are distinguished through their respective operating pressures.

Zurück zur Listen Ansicht