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IEEE Journal of Lightwave Technology
Volume 18 Number 4, April 2000

Table of Contents for this issue

Complete paper in PDF format

Characterization of Defects in Waveguides Formed by Electron Irradiation of Silica-on-Silicon

Susan M. R. Spaargaren, Member, IEEE and Richard R. A. Syms Member, IEEE

Page 555.

Abstract:

Absorption spectroscopy and electron spin resonance are used to characterize optical waveguides formed by electron irradiation of plasma-enhanced chemical vapor deposition (PECVD) silica-on-silicon. Nonbridging oxygen hole centers and E' defect centers are positively identified in undoped films. Evidence for peroxy radical and phosphorus oxygen hole centers is also found in phosphorus-doped samples. This is the first time that defects have been unambiguously identified in such guides. The charge-dose dependence of the E' center density follows a saturating exponential curve well correlated with refractive index changes previously reported, implying that a single first order process is responsible for both effects.

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