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New developments in IR photoelastic stress measurement methods for characterization of semiconductors. / CUHK electronic theses & dissertations collection

In this thesis work, a novel low level birefringence detection (LLBD) system operating at 1150 nm was set up based on the photoelastic modulation techniques. The noise level of current LLBD system is about 0.03° and the maximum fluctuation of data in ten measurements is 0.05° and close to the noise level of system. With a slit confining the light, the spatial resolution of the system is 10 mum. Optical orientation and retardation can be simultaneously measured by this system, making the stress measurement more convenience than the traditional PE methods. These peculiar features make this system capable of investigating the details of stress distribution in semiconductor structures. / Our solution reveals that the nonlinear stress filed is responsible for the shift of the zero stress point. Further it is indicated that the classical Stoney formula can either overestimate or underestimate the actual film stress due to the process induced nonlinear stress in the substrate. / Stress and strain play an essential role in determining the structural, electrical, and optical properties of semiconductor materials, and, ultimately, the semiconductor device performance. Many methods have been utilized to measure the stress in semiconductors. Among them infrared photoelasticity method is a promising one, which can be used both in the industrial characterization and scientific research. This thesis is an endeavor in this subject matter and will present our research results of studying the stress problems in semiconductor structures by using infrared photoelasticity method. / The LLBD system was applied to measure the stress distributions in the substrates of SiO2/Si structure. Some deviations from the classical film theory were observed in our experiments. For example non-linear stress fields were observed in all samples whatever their process conditions are. Besides the locations of neutral axis (zero stress point) was not located at the depth of 2/3 thickness of the substrate from the interface as expected by the bi-metallic theory. To interpret these deviations, a theoretical analysis was given to investigate the problem of stress distribution in film/substrate structure. A series of solutions were deduced to modify the Stoney formula and bi-metallic strip theory with the consideration of the nonlinear stress in substrate. / by Liu Xianghua. / "Feb 2006." / Adviser: Sai Peng Wong. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6674. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Identiferoai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_343785
Date January 2006
ContributorsLiu, Xianghua., Chinese University of Hong Kong Graduate School. Division of Electronic Engineering.
Source SetsThe Chinese University of Hong Kong
LanguageEnglish, Chinese
Detected LanguageEnglish
TypeText, theses
Formatelectronic resource, microform, microfiche, 1 online resource (x, 103, [5] p. : ill.)
RightsUse of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

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