Micro-Raman strain measurement

In this section, we examine the internal stress within the cotton fibers treated with SMPU and DMDHEU. Eichhom and Young (Eichhom et al, 2001 Eichhom and Yoimg, 2001,2003 Eichhom eta/., 2003) showed that the internal stress of cellulose fibers can be measured by shifts of C-O-C vibrations in the Raman spectrum an increase in the wave intensity indicates a reduction of the internal stress, and vice versa. Using the strain-induced shift in the special Raman peak, incorporated with micro-Raman spectroscopy, is a technique unique to micro-mechanics. A Raman spectrum of imtreated cotton is shown in Fig. 10.15. The C-O-C peaks are 1096 and 960cm , depending on the internal stress of the cellulose chain. 

Wright of Advanced Micro Devices discusses the use of Raman microspectroscopy to measure the integrity of a film on semiconductor wafers during manufacture in US patent 6,509,201 and combined the results with other data for feed-forward process control [181]. Yield is improved by providing a tailored repair for each part. Hitachi has filed a Japanese patent application disclosing the use of Raman spectroscopy to determine the strain in silicon semiconductor substrates to aid manufacturing [182]. Raman spectroscopy has a well established place in the semiconductor industry for this and other applications [183]. 

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