Non-Equilibrium Nanoscale Self-Organization

Aziz, Michael J

President & Fellows of Harvard College

关键词: 77 Nanoscience And Nanotechnology;   

DOI  :  10.2172/1040627
RP-ID  :  DOE-ER45947- Final Report
RP-ID  :  FG02-01ER45947
RP-ID  :  1040627

美国|英语

来源: UNT Digital Library

【 摘 要 】

Self-organized one- and two-dimensional arrays of nanoscale surface features ("ripples" and "dots") sometimes form spontaneously on initially flat surfaces eroded by a directed ion beam in a process called "sputter patterning". Experiments on this sputter patterning process with focused and unfocused ion beams, combined with theoretical advances, have been responsible for a number of scientific advances. Particularly noteworthy are (i) the discovery of propagative, rather than dissipative, behavior under some ion erosion conditions, permitting a pattern to be fabricated at a large length scale and propagated over large distances while maintaining, or even sharpening, the sharpest features; (ii) the first demonstration of guided self-organization of sputter patterns, along with the observation that defect density is minimized when the spacing between boundaries is near an integer times the natural spatial period; and (iii) the discovery of metastability of smooth surfaces, which contradicts the nearly universally accepted linear stability theory that predicts that any surface is linearly unstable to sinusoidal perturbations of some wave vector.