Low threshold electron emission from planar AlN/Silicon heterostructures is reported. The surface emitting
ballistic electron structure consisted of an undoped AlN layer grown on Silicon by Molecular Beam Epitaxy, a
Ti/Au Ohmic contact, and a thin Pt Schottky contact fabricated by e-beam deposition. Tunnel-transparent Pt
Schottky contact was deposited on a 1 μm thick Silicon Dioxide (SiO2) layer and covered a 4 x 4 matrix of 50 μm
diameter via produced in the SiO2 layer using photolithography The measurements were performed in vacuum (~10-8 Torr) using a metal grid separated from the structure by a 60 micron thick Kapton® polyimide film having an
opening aligned with the via. Bias voltages in the range of 0-130 V were applied across the Schottky diode, while
currents were recorded across the structure for grid voltages ranging from 0 to 50 V. The field emission nature of the
measured currents was confirmed by plotting the Fowler-Nordheim dependence. Current density of at least 2.5x10-4A/cm2 was achieved for a grid voltage of 50 V and a bias of 130 V. Degradation of the structure performance was
observed at bias voltages exceeding 90 V as a result of Schottky barrier modification under the elevated temperature
and high electric field operation. The solid-state electron emitting structure indicated a threshold field as low as 0.2
V/μm under applied grid voltage of 12 V.
Employment of layered structures made of semiconductor materials with different optical absorption bands is a new way of realizing either broad band spectrum or selective multiple band photodetectors. A new concept of structures fabricated using stacked semiconducting layers to obtain a multi band spectral response is reported. Based on this approach, fabrication of a Solar-blind dual-band UV/IR photodetectors is demonstrated. Optimization of the device was carried out by modeling of the electric field distribution and developing tunneling barriers. The optimized Solar-blind UV/IR photodiode UV spectral response turns-on approximately around 265 nm (solar-blind) and peaks at 230 nm with a responsivity of approximately 0.0018 A/W. The IR diode response peaks at 1000nm with a responsivity of approximately 0.01 A/W.
Employment of layered structures made of semiconductor materials with different optical absorption bands is a new way of realizing either broad band spectrum or selective multiple band photodetectors. A new concept of structures fabricated using stacked semiconducting layers to obtain a multi band spectral response is reported. Based on this approach, fabrication of a Solar-blind dual-band UV/IR photodetectors is demonstrated. Optimization of the device was carried out by modeling of the electric field distribution and developing tunneling barriers. The optimized Solar-blind UV/IR photodiode UV spectral response turns-on approximately around 265 nm (solar-blind) and peaks at 230 nm with a responsivity of approximately 0.0018 A/W. The IR diode response peaks at 1000nm with a responsivity of approximately 0.01 A/W.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
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.