Patented Core Technology: CQD® Sensors
SWIR Vision Systems® has introduced a new class of cameras featuring a 400nm to 1,700nm broadband image sensor technology based on colloidal quantum dot (CQD) thin film photodiodes fabricated monolithically on silicon readout wafers.
These sensors have the potential to achieve for SWIR imaging, what CMOS image sensors and micro-bolometer arrays have achieved for visible and longwave infrared imaging respectively.
Namely, to leverage the scale and cost structure of the silicon integrated circuit industry, moving SWIR imaging from a specialized niche into broad commercial markets.
HOW IT WORKS
The Acuros® CQD® camera products use our patented CQD sensor technology. CQD sensors are fabricated using low-cost deposition techniques to produce quantum dot photodiodes directly on CMOS readout integrated circuits (ROICs).SWIR Vision Systems’ CQD sensor technology uses a monolithic integration approach, in which the quantum dot-based sensor is fabricated directly onto CMOS readout integrated circuits (ROICs) using well-established, low-cost semiconductor deposition techniques.The process requires no hybridization, no epitaxial growth or exotic substrate materials, and can be easily scaled to wafer-level fabrication.The approach also employs low-cost, colloidal quantum dots to form as small as sub-2μm pitch p-n photodiode arrays sensitive in both the SWIR and visible spectral bands.
- Encapsulant
- Transparent Electrode
- Other Thin Film Layers
- Quantum Dots
- Metal Pixel Electrode
- CMOS-based read-out integrated circuit (ROIC)
The CQD® Process:
The process requires no hybridization, no epitaxial growth or exotic substrate materials, scaling easily to high volume production. The approach employs low-cost, solution-processed, colloidal quantum dots to form small pitch p-n photodiode arrays sensitive in both the SWIR and visible spectral bands.
How it Stacks up
Today the SWIR imaging market is dominated by InGaAS sensors whose fabrication method imposes limitations on pixel size, pixel spacing and sensor resolution. With the introduction of SWIR’s Acuros CQD Sensor, production is more affordable and easier to scale, without sacrificing performance.
- Lower resolution
- Not volume scalable
- Not cost scalable
- Difficult to export
Acuros CQD SWIR
- Higher resolution
- Scalable to high volume
- Scalable to very low cost
- EAR99 for global export
InGaAs SWIR
- Lower resolution
- Not volume scalable
- Not cost scalable
- Difficult to export
Acuros CQD SWIR
- Higher resolution
- Scalable to high volume
- Scalable to very low cost
- EAR99 for global export
SWIR CQD Sensor Vs Indium Gallium Arsenide (InGaAs) Sensor
The current SWIR imaging market is dominated by indium gallium arsenide (InGaAs) sensors, a compound semiconductor grown epitaxially on lattice-matched indium phosphide (InP) substrates.
The fabrication method imposes limitations on pixel size, pixel spacing, and sensor resolution; commercially practical InGaAs SWIR cameras are limited to VGA resolution, and even these are considered too costly for most machine vision applications.
