integrated oled/opv planar “onchip” refractometer
TRANSCRIPT
Integrated OLED/OPV Planar “On-Chip” Refractometer
Brian Zacher, Alex Veneman Dan Huebner, Adam Simmonds, Neal R. Armstrong
Dept. of Chemistry, University of Arizona
Goal Statement
Integrate OLEDs and OPVs onto/into functionalized waveguide structures and perform spectroscopy.
-transition from bulky free space optical instrumentation to compact and inexpensive integrated device
www.bruker.com
Essence of Operation
• Forrest et. al., PRB, 58, 7,
3730-3740 (1998)
• Noda et. al., Organic
Electronics, 6, 3-9 (2005)
• McGehee et. al., J. Appl.
Phys., 97, (2005)
• Neyts, K., Applied Surface
Science, 244, 517-523,
(2005)
Significant Fractions of OLED Emission Are Lost into WG or “Substrate” Modes
-For OLED based “displays” this is inefficient……but
provides great potential for ATR spectroscopy!
Functions as described by Snell’s Law
Change in crit. angle =
Change in # photons reaching OPV
Critical Contributors of Technology and Inspiration For Organic Sensors
Meerholz, et. al., Adv. Mater., 20, 1966-1971 (2008).
Shinar(s), et. al., Analytica Chim Acta., 568, 190-199 (2006).
Bradley et. al., Lab Chip, 7, 58-63 (2007).
Ohmori et. al., IEEE Journal of Selected Topics in Quantum Electronics, 10,1, 70-78 (2004).
Integration of Light Sources and Detectors on a Single Chip
ATR/Waveguide
Element
OLED OPV OPV
Side View
Top View
OLED/OPV – Dual Beam ATR Photometer/Refractometer Platforms
gla
ss
ITO
C60
Al
Pc
BC
P CuPc/C60
TiOPc/C60
Small Molecule OLEDs and OPVs
ITO/PEDOT/TPD/Alq3/Mg:Ag
OLEDs
OPVs
OPV Short-Circuit Current as a Function of OLED Current
•0.002% external quantum efficiency
•1% OLED
•5% OPV
Experimental – Measure Refractive Index of Sucrose-Water Solution
•Sucrose-Water R.I. values published for 1E-5 resolutions
•~+1.6E-4 R.I. units per 0.1 wt.%
•Essentially zero absorbance of visible light (can ignore imaginary R.I. term)
Reference Cells
Sample Cells
Instrumentation
Key Features: o Battery Powered
o Mobile, low noise o OLED driven with pulsed
constant-current o Supports lock-in, thermal
o OPV monitored in short-circuit mode o Linear current response,
low shot noise o Integrated Lock-In amplifier
o Dual-Beam o Real-time baseline
Future Work
• Brighter OLEDs more efficient OPVs
• Integrate onto/into a single-mode waveguide
– 100 - 1000x increase in sensitivity
– Current device is ~80,000 mode
• Spectroscopy
– Narrow band light sources/detectors
– Multiple source/detector pairs on single substrate
Students/Collaborators/Research Support
Alex Veneman, Adam Simmonds, Dan Huebner, Erin Ratcliff
Contact me: Brian Zacher
bzacher@ email.arizona.edu 520 488 7261
Research support: National Science Foundation (CHE-0517963) NSF-STC CMDITR (DMR 0120967) Office of Naval Research