By Topic

Process issues with Mo/a-Si:H Schottky diode and thin film transistors integration for direct x-ray detection

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
Czang-Ho Lee ; Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada ; Vygranenko, Y. ; Nathan, A.

Your organization might have access to this article on the publisher's site. To check, click on this link: 

This article presents an alternate strategy to reduce mechanical stress issues pertinent to the process integration of molybdenum/hydrogenated amorphous silicon (Mo/a-Si:H) Schottky diodes and thin film transistors (TFTs), used as x-ray sensor pixels for medical imaging. The previous approach was to minimize the intrinsic stress in the Mo layer through appropriate process conditions and film thickness. However, that approach resulted in narrow process latitude and compromised x-ray sensitivity. Alternatively, the mechanical stress in the Mo can be reduced by reducing and/or avoiding the extrinsic stress exerted on the Mo by the underlying films through a different masking sequence in the fabrication. This modified process allows for a more flexible design of the Mo layer for enhanced x-ray sensitivity, while maintaining the mechanical integrity of the various layers. Also, the performance of the Schottky diode is improved in terms of its forward current. The x-ray sensitivity has been measured at different x-ray spectra in the range of 40–100 kVp. The pixel shows good linearity with x-ray dosage and high detection efficiency at low x-ray tube voltages.

Published in:

Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films  (Volume:22 ,  Issue: 5 )