BYU

Abstract by Ryan Vanfleet

Personal Infomation


Presenter's Name

Ryan Vanfleet

Co-Presenters

None

Degree Level

Undergraduate

Co-Authors

None

Abstract Infomation


Department

Physics and Astronomy

Faculty Advisor

Robert Davis, Richard Vanfleet, David Allred

Title

Controlling Reactant Exposure in Tungsten Atomic Layer Deposition

Abstract

A homebuilt Atomic Layer Deposition (ALD) system for the deposition of tungsten (W) on Carbon Nanotubes (CNTs) has been recently rebuilt. The initial configuration of the ALD system led to waste of the reactants, Silane (SiH4) and tungsten hexafluoride (WF6). The completed reconfiguration did not produce the expected attenuation of reactant pressures in the deposition chamber. A study of process valve speeds revealed sub-optimal programming and slowly-closing valves that explain the lack of pressure attenuation. CNT forests show non-uniform deposition in the form of abrupt steps (spaced 10-100 um apart) of decreasing W thickness and small, localized areas of increased deposition (about 1 um in diameter). The non-uniform depositions seem to be a function of exposure (pressure*time) to the ALD reactants.