Under the
sponsorship of Bruker AXS, Inc., the UC Davis Vacuum Microelectronic Team
are undertaking the task of inventing a novel and innovative
high-resolution X-ray imaging detector using Field Emission Array (FEA)
technology. The objective of this research is to design, fabricate, and
test the second phase of the Bruker X-ray detection project, using
highly-planar, gated, photosensitive, (FEA) photocathode.
The gated FEAs are fabricated using subtractive etching techniques
and include Chemo-Mechanical-Polishing for a planar-gate surface. The
advantages of implementing a planar-gate include higher spatial
resolution, enhanced dynamic range, reduced gate-cathode capacitance, and
a lower turn-on voltage (which reduces the chance of damage being caused
by high-voltage dielectric breakdown.) Previous planar, gated designs
from other FEA groups show promising results, but have certain
deficiencies. This design of gated-FEA photocathode has the potential
advantages of a planar gate surface, and can alleviate problems associated
with non-self-aligned gate openings and uneven fabrication over a
large-area array.