Organic Photodiodes

Organic photodiodes enable new devices and applications that cannot be made with conventional semiconductors.

Features of OPD Technology

Organic Photodiodes provide key differentiating features compared with traditional photodiode technology including:

  • Thin and lightweight form factor
  • Flexible and conformable devices
  • Potential for low cost fabrication processes
  • Ease of integration with other printed electronics components and systems

Electrode / Electron Transport Layer / OPV Layer / Hole Transport Layer / Transparent Anode(ITO) / Glass

Applications

OPD devices can be fabricated on plastic substrates, which enables devices that are thin, light-weight, flexible and easily integrated. This expands the range of OPD applications to include: pulse oximeter, optical biosensor, digital x-ray image sensor, proximity sensor, low cost spectrometer, finger print sensor, gesture sensor, array sensor etc.

Example Applications:

Pulse Oximeter

  • Differential signal from two
    OLEDs detected by OPD
  • Heart rate and oxygenation level of the blood is calculated
  • OLED and OPD can be integrated on the same substrate

Optical Biosensor

  • OLED/OPD coupled devices
  • Quantitative read out of absorption or fluorescent signals from biological elements
  • Signal correlates with biomarker concentration in sample

Example Application: OPD Proximity Sensor Switching OLEDs

OPD output switches the OLED

Features of OPD materials

The absorption spectrum of our OPD materials can be tuned throughout the visible & near-infra-red, so that the detection range can be tailored to the application.
Air stable cathodes producing a high device efficiency can be deposited either by vacuum deposition or printing. An electron transport layer is not required when using an evaporated air stable cathode.
Efficiency of more than 40% (external quantum efficiency) across the visible spectrum and into the near infra-red are possible.

Donor Material Absorption Tuning

OLED/OPWe offer a range of donor materials for OPD applications. Absorption of materials can be tuned as is highlighted below for a series of research materials

Optical absorption of materials

Spectral cell efficiency as a function of donor selection

Organic vs Silicon Photodiode Device Performance

Metric OPD Si-PD
EQE - 50%
(-1V bias)
30% at 400nm rising
to 85% at 800nm
Wavelength
range
400 - 800nm 400 - 1100nm
(typical)
Responsivity (R) > 0.15A/W at 400nm
> 0.29A/W at 800nm
Approx. Linear from
- 0.15 A/W at 400nm
- 0.60 A/W at 950nm
Dark current
(at -0.5V)
< 50nA/cm2 10 - 100pA/cm2
at -5V
Linear Dynamic
Range (LDR)
72dB 120dB
Response time
(rise/fall time)
5μs
(10㎜2)
50 - 100ns (100㎜2)
(area dependent)

Organic photodiode performance is comparable to silicon on many metrics

If you have any questions and requests for business discussion and quotation,
please feel free to contact us.