Research: Ruth Shinar and Joe Shinar
We are developing novel fluorescence-based chemical and biological sensors that are structurally integrated
with an organic light emitting device (OLED) excitation source. Examples include oxygen, hydrazine, and
glucose sensors as well as immunoassays. While OLEDs and fluorescent chemical sensors are not novel,
their integration is. The sensing component is fabricated on one side of a glass or plastic substrate,
while the light-source required to excite the fluorescence (i.e., an OLED array) is fabricated on
the other side. Such integrated sensors will be compact, battery-operated, inexpensive
(eventually disposable), automated, and remotely-operated. This integration addresses the need for
miniaturized devices in medical and environmental testing, high-throughput drug discovery, and detection
of inorganic gases, volatile organic compounds (VOCs), pathogens, warfare agents, and in-vivo biological
compounds and organisms. In developing the devices, we optimize the performance of the sensing
components and the OLEDs, to maximize their dynamic range, sensitivity, and stability, while
minimizing power consumption. The OLEDs are fabricated by Joe Shinar’s group.
SENSOR FILM
GLASS OR PLASTIC SUBSTRATE
TRANSPARENT ANODE
ORGANIC LAYERS
CATHODE
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Figure 1. Matrix array of blue OLEDs
each pixel is ~1.5 mm in diameter
Figure 2.. Basic structure of an integrated
OLED/ fluorescent chemical sensor element
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Investigation of hydrogen motion and its relation to film microstructure and hydrogen bonding in
hydrogenated amorphous silicon (a-Si:H) and related materials was performed using secondary ion mass
spectrometry (SIMS) and infrared (IR) absorption spectroscopy. Films, grown by various techniques,
such as rf sputtering, glow discharge, electron cyclotron resonance (ECR), and hot wire, were annealed at
temperatures in the range of 200-400 oC for various periods to obtain the H diffusion profile and the
temperature effect on the Si-H bonding configurations. A better understanding of the parameters that
affect hydrogen motion contributed to the design and fabrication of improved devices. Such parameters
include the microvoid structure, the hydrogen level and bonding, and growth parameters.