Results from Cs activated GaN photocathode development for MCP detector systems at NASA GSFC

Timothy J. Norton; Bruce E. Woodgate; Joseph Stock; George Hilton; Melville P. Ulmer; Shahid Aslam; R. D. Vispute

doi:10.1117/12.507528

8 December 2003 Results from Cs activated GaN photocathode development for MCP detector systems at NASA GSFC

Timothy J. Norton, Bruce E. Woodgate, Joseph Stock, George Hilton, Melville P. Ulmer, Shahid Aslam, R. D. Vispute

Proceedings Volume 5164, UV/EUV and Visible Space Instrumentation for Astronomy II; (2003) https://doi.org/10.1117/12.507528
Event: Optical Science and Technology, SPIE's 48th Annual Meeting, 2003, San Diego, California, United States

Abstract

We describe the development of high quantum efficiency UV photocathodes for use in large area two dimensional microchannel plated based, detector arrays to enable new UV space astronomy missions. Future UV missions will require improvements in detector sensitivity, which has the most leverage for cost-effective improvements in overall telescope/instrument sensitivity. We use new materials such as p-doped GaN, AlGaN, ZnMgO, SiC and diamond. We have currently obtained QE values > 40% at 185 nm with Cesiated GaN, and hope to demonstrate higher values in the future. By using controlled internal fields and nano-structuring of the surfaces, we plan to provide field emission assistance for photoelectrons while maintaining their energy distinction from dark noise electrons. We will transfer these methods from GaN to ZnMgO a new family of wide band-gap materials more compatible with microchannel plates. We also are exploring technical parameters such as doping profiles, internal and external field strengths, angle of incidence, field emission assistance, surface preparation, etc.

Citation Download Citation

Timothy J. Norton, Bruce E. Woodgate, Joseph Stock, George Hilton, Melville P. Ulmer, Shahid Aslam, and R. D. Vispute "Results from Cs activated GaN photocathode development for MCP detector systems at NASA GSFC", Proc. SPIE 5164, UV/EUV and Visible Space Instrumentation for Astronomy II, (8 December 2003); https://doi.org/10.1117/12.507528

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