Visible-Blind UV Digital Camera Based On a 32 x 32 Array of GaN/AlGaN p-i-n Photodiodes
J.D. Brown, Zhonghai Yu, J. Matthews, S. Harney, J. Boney, J.F. Schetzina
Department of Physics, North Carolina State University
J.D. Benson, K.W. Dang, C. Terrill
Night Vision Laboratory, Ft. Belvoir, VA
Thomas Nohava, Wei Yang, Subash Krishnankutty
Honeywell Technology Center
This article was received on Wednesday, August 25, 1999 and
accepted on Friday, September 3, 1999. Abstract
A
visible-blind UV camera based on a 32 x 32 array of backside-illuminated
GaN/AlGaN p-i-n photodiodes has been successfully demonstrated. Each of the
1024 photodiodes in the array consists of a base n-type layer of AlGaN (~20%)
onto which an undoped GaN layer followed by a p-type GaN layer is deposited by
metallorganic vapor phase epitaxy. Double-side polished sapphire wafers are
used as transparent substrates. Standard photolithographic, etching, and
metallization procedures were employed to obtain fully-processed devices. The
photodiode array was hybridized to a silicon readout integrated circuit using
In bump bonds. Output from the UV camera was recorded at room temperature at a
frame rate of 30 Hz. This new type of visible-blind digital camera is
sensitive to radiation from 320 nm to 365 nm in the UV spectral region.
