Investigation of defects in highly photosensitive germanosilicate thin films

Kelly Simmons-Potter; Barrett G. Potter Jr.; W. L. Warren

doi:10.1117/12.264170

23 January 1997 Investigation of defects in highly photosensitive germanosilicate thin films

Kelly Simmons-Potter, Barrett G. Potter Jr., W. L. Warren

Proceedings Volume 2998, Photosensitive Optical Materials and Devices; (1997) https://doi.org/10.1117/12.264170
Event: Photonics West '97, 1997, San Jose, CA, United States

Abstract

Germanosilicate glasses exhibit a significant photosensitive response which has been linked to the presence of oxygen- deficient germanium point defects in the glass structure. Based on this correlation, highly photosensitive thin films have been engineered which demonstrate the largest reported ultraviolet-induced refractive index perturbations ((Delta) n) in an as-synthesized material. Our thin-film fabrication process avoids the use of hydrogen sensitizing treatments and, thus, yields stable films which retain their predisposition for large photosensitivity for over one year of storage. Understanding the nature of the defects in such films and their relationship to charge trapping and enhanced photosensitivity is of paramount importance in designing and optimizing the materials. Toward this end, our films have been studied using electron paramagnetic resonance (EPR), capacitance-voltage, and optical bleaching and absorption spectroscopies. We find experimental evidence suggesting a model in which a change in spin state and charge state of isolated paramagnetic neutral Ge dangling bonds form either diamagnetic positively or negatively charged Ge sites which are largely responsible for the charge trapping and photosensitivity in these thin films. We present experimental data and theoretical modeling to support our defect model and to show the relevance of the work.

Citation Download Citation

Kelly Simmons-Potter, Barrett G. Potter Jr., and W. L. Warren "Investigation of defects in highly photosensitive germanosilicate thin films", Proc. SPIE 2998, Photosensitive Optical Materials and Devices, (23 January 1997); https://doi.org/10.1117/12.264170

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available