TY - THES

T1 - The effect of a pulsed plasma based substrate electron bombardment on the properties of sputtered CrC/a-C:H coatings

AU - Lechthaler, Markus

N1 - no embargo

PY - 2005

Y1 - 2005

N2 - Pulsed plasma based electron bombardment of the substrate during deposition is an innovative approach for the design of coatings produced by physical vapour deposition (PVD). It leads to a stabilization of an internal structure looking like synthesized at a temperature higher than the effectively adjusted substrate temperature. This can be attractive for depositing films with a high temperature structure on substrates which do not support elevated temperatures. A modern and highly investigated class of materials very sensitive to thermal parameters is carbide containing diamond-like carbon. Hence, during the deposition of CrC/a-C:H coatings the bias voltage was superposed by a power supply delivering positive bias pulses up to a length of 60 ms and a pulse interval of several seconds. The deposition has been conducted by unbalanced magnetron sputtering of a chromium target in an Ar/CH4 atmosphere. Structural changes attributed to the positive bias pulsing have been identified by X-ray photoelectron spectroscopy and transmission electron microscopy. Additionally, an improved thermal stability of the structure is evidenced by a high temperature x-ray diffraction pattern (HT-XRD) up to 800 °C. Dry sliding tests indicate a slight improvement of the tribological properties for relatively intensive pulsed coatings.

AB - Pulsed plasma based electron bombardment of the substrate during deposition is an innovative approach for the design of coatings produced by physical vapour deposition (PVD). It leads to a stabilization of an internal structure looking like synthesized at a temperature higher than the effectively adjusted substrate temperature. This can be attractive for depositing films with a high temperature structure on substrates which do not support elevated temperatures. A modern and highly investigated class of materials very sensitive to thermal parameters is carbide containing diamond-like carbon. Hence, during the deposition of CrC/a-C:H coatings the bias voltage was superposed by a power supply delivering positive bias pulses up to a length of 60 ms and a pulse interval of several seconds. The deposition has been conducted by unbalanced magnetron sputtering of a chromium target in an Ar/CH4 atmosphere. Structural changes attributed to the positive bias pulsing have been identified by X-ray photoelectron spectroscopy and transmission electron microscopy. Additionally, an improved thermal stability of the structure is evidenced by a high temperature x-ray diffraction pattern (HT-XRD) up to 800 °C. Dry sliding tests indicate a slight improvement of the tribological properties for relatively intensive pulsed coatings.

KW - sputtering

KW - reactive electron-bombardment

KW - substrate bias

KW - pulsed DLC CrC/a-C:H

KW - Reaktivsputtern Elektronenbeschuss

KW - Substrat Biasspannung

KW - gepulst DLC CrC/a-C:H

M3 - Diploma Thesis

ER -