Micro-material handling employing e-beam generated topographies of copper and aluminium

 

 

S. Matope^I; A.F. van der Merwe^II; R. Nemutudi^III; M. Nkosi^IV; M. Maaza^V

^IDepartment of Industrial Engineering, University of Stellenbosch, South Africa^, smatope@sun.ac.za
^IIDepartment of Industrial Engineering, University of Stellenbosch, South Africa, avdm@sun.ac.za
^IIIDepartment of Material Science, iThemba Labs, South Africa, rudzi@tlabs.ac.za
^IVDepartment of Material Science, iThemba Labs, South Africa, mlungisin@tlabs.ac.za
^VDepartment of Material Science, iThemba Labs, South Africa, maaza@tlabs.ac.za

 

 

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ABSTRACT

This paper focuses on the employment of copper and aluminium in a micro-material handling system actuated by Van der Waals forces. Electron beam (e-beam) evaporator deposited both materials on a silicon substrate at a rate of 0.6-1.2 Angstroms/second, vacuum pressure between 2x10^-6 and 3x10^-6mbar, and at a current less than 10mA. A Veeco NanoMan V Atomic Force Microscope with Nanoscope version 7.3 software was used to analyse the root mean square (rms) surface roughnesses of the generated topographies. Rumpf-Rabinovich's rms formula was used to determine the Van der Waals forces exerted by the surfaces. It was synthesised that an e-beam deposition of 7 minutes' duration on both materials produced an optimum micro-material handling solution, with copper suitable for the pick-up position and aluminium for the placement position.

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OPSOMMING

Die fokus van die artikel is op die gebruik van koper en aluminium in 'n mikromateriaalhanteringstelsel, aangedryf deur Van der Waalskragte. 'n Elektronstraal-verdamper plaas albei materiale op 'n silikonbasis teen 'n tempo van 0.6-1.2 Angstrom/sekonde, vakuumdruk tussen 2x10^-6 en 3x10^-6mbar, en teen 'n stroom van minder as 10mA. 'n Veeco NanoMan V Atomic Force mikroskoop, met Nanoscope 7.3 program-matuur is gebruik om die wortel-gemiddelde-kwadraat (wgk) oppervlak ruheid van die gegenereerde topografieë te analiseer. Rumpf-Rabinovich se wgk-formule is gebruik om die Van der Waalskrage wat deur die oppervlaktes uitgeoefen word te bepaal. Dit is vasgestel dat 'n elektronstraalafsetting van 7 minute op albei materiale die optimale materiaalhanteringoplossing bied, met koper geskik vir die optelposisie en aluminium vir die plasingsposisie.

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* Corresponding author.
1 The author was enrolled for a PhD (Manufacturing Engineering) degree in the Department of Industrial Engineering, University of Stellenbosch.