The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	Laser ablation of silicon surfaces : the effects of a low level background light
Author:	Gayen, Taposh Kumar
View Online:	njit-etd1993-085 (xv, 99 pages ~ 5.7 MB pdf)
Department:	Committee for the Interdisciplinary Program in Materials Science and Engineering
Degree:	Master of Science
Program:	Materials Science and Engineering
Document Type:	Thesis
Advisory Committee:	Grebel, Haim (Committee chair) Levy, Martin J. (Committee member) Kristol, David S. (Committee member)
Date:	1993-10
Keywords:	Laser fusion -- Industrial applications Ablation (Aerothermodynamics) Semiconductors -- Etching Silicon Surfaces (Technology)
Availability:	Unrestricted
Abstract:	The performance of high speed optoelectronic and microelectronic devices largely depends on the uniqueness and development of the fabrication technology. Laser ablation has proven to be an effective three dimensional surface patterning technology. In this thesis, we present findings on the patterning of semiconductor surfaces using laser ablation in air as well as in solutions. In this thesis, we suggest that the depth of a pattern induced on silicon by firing a pulsed excimer laser in air varies almost linearly with the number of pulses. We report that a He-Ne laser as a background light source has virtually little or no effect on the etching rate. We also suggest that a background light enhances the etching process induced by the excimer laser in wet chemical etching when using a thin-film cell configuration. Pattern depth profiles have been measured by scanning electron microscopy (SEM). We verify our SEM findings by using a light diffraction measurement technique. Finally, we report on the effect of patterning on the electrical properties of metal-semiconductor contacts. Schottky barriers measured for grooved surface showed, in general, a decrease in the barrier height.