Ion assisted deposition of thin films by substrate tuned radio frequency magnetron sputtering

The substrate tuning technique was applied to a radio frequency magnetron sputtering system to obtain a variable substrate bias without an additional source. The dependence of the substrate bias on the value of the external impedance was studied for different values of chamber pressure, gas composit...

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Detalles Bibliográficos
Autores: Lousa Rodríguez, Arturo, Gimeno, S.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1997
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/25053
Acceso en línea:https://hdl.handle.net/2445/25053
Access Level:acceso abierto
Palabra clave:Pel·lícules fines
Radiofreqüència
Ions
Nitrur de bor
Thin films
Radio frequency
Boron nitride
Descripción
Sumario:The substrate tuning technique was applied to a radio frequency magnetron sputtering system to obtain a variable substrate bias without an additional source. The dependence of the substrate bias on the value of the external impedance was studied for different values of chamber pressure, gas composition and rf input power. A qualitative explanation of the results is given, based on a simple model, and the role of the stray capacitance is clearly disclosed. Langmuir probe measurements show that this system allows independent control of the ion flux and the ion energy bombarding the growing film. For an argon flow rate of 2.8 sccm and a radio frequency power of 300 W (intermediate values of the range studied) the ion flux incident on the substrate was 1.3 X 1020-m-2-s-1. The maximum ion energy available in these conditions can be varied in the range 30-150 eV. As a practical application of the technique, BN thin films were deposited under different ion bombardment conditions. An ion energy threshold of about 80 eV was found, below which only the hexagonal phase was present in the films, while for higher energies both hexagonal and cubic phase were present. A cubic content of about 60% was found for an ion energy of 120 V.