About this Journal Submit a Manuscript Table of Contents
Advances in Materials Science and Engineering
Volume 2014 (2014), Article ID 948708, 6 pages
http://dx.doi.org/10.1155/2014/948708
Research Article

Improvement of Homogeneity and Aspect Ratio of Silicon Tips for Field Emission by Reactive-Ion Etching

Faculty of General Sciences and Microsystems Technology, OTH Regensburg, 93053 Regensburg, Bavaria, Germany

Received 16 February 2014; Accepted 9 March 2014; Published 6 April 2014

Academic Editor: Feng Zhao

Copyright © 2014 Robert Damian Lawrowski et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The homogeneity of emitters is very important for the performance of field emission (FE) devices. Reactive-ion etching (RIE) and oxidation have significant influences on the geometry of silicon tips. The RIE influences mainly the anisotropy of the emitters. Pressure has a strong impact on the anisotropic factor. Reducing the pressure results in a higher anisotropy, but the etch rate is also lower. A longer time of etching compensates this effect. Furthermore an improvement of homogeneity was observed. The impact of uprating is quite low for the anisotropic factor, but significant for the homogeneity. At low power the height and undercut of the emitters are more constant over the whole wafer. The oxidation itself is very homogeneous and has no observable effect on further variation of the homogeneity. This modified fabrication process allows solving the problem of inhomogeneity of previous field emission arrays.