Gallium nitride photocathodes for imaging photon counters

Details Gallium nitride photocathodes for imaging photon counters Gallium nitride photocathodes for imaging photon counters

Jul 2010

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010spie.7732e.152s&link_type=abstract

Space Telescopes and Instrumentation 2010: Ultraviolet to Gamma Ray. Edited by Arnaud, Monique; Murray, Stephen S.; Takahashi,

Statistics

Applications

1

Scientific paper

Gallium nitride opaque and semitransparent photocathodes provide high ultraviolet quantum efficiencies from 100 nm to a long wavelength cutoff at ~380 nm. P (Mg) doped GaN photocathode layers ~100 nm thick with a barrier layer of AlN (22 nm) on sapphire substrates also have low out of band response, and are highly robust. Opaque GaN photocathodes are relatively easy to optimize, and consistently provide high quantum efficiency (70% at 120 nm) provided the surface cleaning and activation (Cs) processes are well established. We have used two dimensional photon counting imaging microchannel plate detectors, with an active area of 25 mm diameter, to investigate the imaging characteristics of semitransparent GaN photocathodes. These can be produced with high (20%) efficiency, but the thickness and conductivity of the GaN must be carefully optimized. High spatial resolution of ~50 μm with low intrinsic background (~7 events sec-1 cm-2) and good image uniformity have been achieved. Selectively patterned deposited GaN photocathodes have also been used to allow quick diagnostics of optimization parameters. GaN photocathodes of both types show great promise for future detector applications in ultraviolet Astrophysical instruments.

Affiliated with

Also associated with

No associations

Rating

Gallium nitride photocathodes for imaging photon counters does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Gallium nitride photocathodes for imaging photon counters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gallium nitride photocathodes for imaging photon counters will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1375677