The potential of GaN based materials for x-ray detection is investigated. The absorption coefficient in GaN is measured as a function of photon energy between 6 and 40keV. Metal-semiconductor-metal photodetectors are fabricated and characterized. The response dependence on bias, the temporal dynamics, and the response dependence on detector geometry all together point toward a mixing of photovoltaic and photoconductive effects. Thanks to a large photoconductive gain, the detector has a decent responsivity at the expense of a large response time.

1.
F.
Binet
,
J. Y.
Duboz
,
E.
Rosencher
,
F.
Scholz
, and
V.
Härle
,
Appl. Phys. Lett.
69
,
1202
(
1996
).
2.
P.
Long
,
S.
Varadaraajan
,
J.
Matthewes
, and
J. F.
Schetzina
,
Opto-Electron. Rev.
10
,
251
(
2002
).
3.
J.-Y.
Duboz
,
N.
Grandjean
,
A.
Dussaigne
,
M.
Mosca
,
J.-L.
Reverchon
,
P. G.
Verly
, and
R. H.
Simpson
,
Eur. Phys. J.: Appl. Phys.
33
,
5
(
2006
).
4.
A.
Motogaito
,
K.
Ohta
,
K.
Hiramatsu
,
Y.
Ohuchi
,
K.
Tadatomo
,
Y.
Hamamura
, and
K.
Fukui
,
Phys. Status Solidi A
188
,
337
(
2001
).
5.
D. S.
Bale
and
C.
Szeles
,
Phys. Rev. B
77
,
035205
(
2008
).
6.
F.
Scholze
,
R.
Klein
, and
Th.
Bock
,
Appl. Opt.
42
,
5621
(
2003
).
7.
See http://physics.nist.gov for atomic attenuation coefficients.
8.
J. Y.
Duboz
,
J. L.
Reverchon
,
D.
Adam
,
B.
Damilano
,
N.
Grandjean
,
F.
Semond
, and
J.
Massies
,
J. Appl. Phys.
92
,
5602
(
2002
).
9.
M.
Mosca
,
J.-L.
Reverchon
,
N.
Grandjean
, and
J.-Y.
Duboz
,
IEEE J. Sel. Top. Quantum Electron.
10
,
752
(
2004
).
10.
A.
Khan
,
J. N.
Kuznia
,
D. T.
Olson
,
J. M.
Van Hove
,
M.
Blaisingame
, and
L. F.
Reitz
,
Appl. Phys. Lett.
60
,
2917
(
1992
).
You do not currently have access to this content.