Morphology evolution on diamond surfaces during ion sputtering

Journal Article · Tue Nov 15 04:00:00 EST 2005 · Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films

DOI:https://doi.org/10.1116/1.2110386· OSTI ID:20723205

Mayer, T M; Adams, D P; Vasile, M J; Archuleta, K M ^[1]

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1. Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

We have conducted an extensive study of the evolution of surface morphology of single crystal diamond surfaces during sputtering by 20 keV Ga{sup +} and Ga{sup +}+H{sub 2}O. We observe the formation of well-ordered ripples on the surface for angles of incidence between 40 and 70 deg.. We have also measured sputter yields as a function of angle of incidence, and ripple wavelength and amplitude dependence on angle of incidence and ion fluence. Smooth surface morphology is observed for <40 deg., and a transition to a step-and-terrace structure is observed for >70 deg.. The formation and evolution of well-ordered surface ripples is well characterized by the model of Bradley and Harper, where sputter-induced roughening is balanced by surface transport smoothing. Smoothing is consistent with an ion-induced viscous relaxation mechanism. Ripple amplitude saturates at high ion fluence, confirming the effect of nonlinear processes. Differences between Ga{sup +} and Ga{sup +}+H{sub 2}O in ripple wavelength, amplitude, and time to saturation of amplitude are consistent with the increased sputter yield observed for Ga{sup +}+H{sub 2}O. For angle of incidence <40 deg., an ion bombardment-induced 'atomic drift' mechanism for surface smoothing may be responsible for suppression of ripple formation. For Ga{sup +}+H{sub 2}O, we observe anomalous formation of very large amplitude and wavelength, poorly ordered surface ridges for angle of incidence near 40 deg.. Finally, we observe that ripple initiation on smooth surfaces can take place by initial stochastic roughening followed by evolution of increasingly well-ordered ripples.

• OSTI ID: 20723205
• Journal Information: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films, Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films Journal Issue: 6 Vol. 23; ISSN 0734-2101; ISSN JVTAD6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DIAMONDS
GALLIUM IONS
INCIDENCE ANGLE
ION BEAMS
KEV RANGE 10-100
MONOCRYSTALS
MORPHOLOGY
RELAXATION
ROUGHNESS
SPUTTERING
WAVELENGTHS