08.24.23
Imec, a research and innovation company for nanoelectrons and digital technologies, has successfully integrated a pinned photodiode structure in thin-film sensors. This allows the potential for sensing light beyond the visible in a cost-efficient way.
This new technology has potential advantages for detecting infrared light in cameras in autonomous vehicles for seeing through fog or smoke as well as cameras for unlocking smartphones though facial recognition.
Imec has demonstrated the first of its kind incorporation of a pinned photodiode (PPD) structure in the readout circuit of a thin-film-based image sensor. Imec monolithically hybridized a SWIR quantum-dot photodetector with an indium-gallium-zinc oxide (IGZO) based thin-film transistor into a PPD pixel. This array was then processed on a CMOS readout circuit to form a thin-film SWIR image sensor.
“The phototype 4T image sensor showed a remarkable low read-out noise of 6.1e-, compared to >1000e- for the conventional 3T sensor, demonstrating its superior noise performance. As a result, infrared images can be captured with less noise, distortion or interference, and more accuracy and detail,” said imec project leader Nikolas Papadopoulous.
“At imec, we are at the forefront of bridging the worlds of infrared and imagers, thanks to our combined expertise in the thin-film photodiodes, IGZO, image sensors and thin-film transistors,” said imec program manager Pawel Malinowski. “By achieving this milestone, we surpassed current pixel architectural limitations and demonstrated a way to combine the best performing quantum-dot SWIR pixel with affordable manufacturing,”
The findings for the project have been published in the August 2023 edition of Nature Electronics ‘Pinned photodiode for monolithic thin-film image sensors.’ The initial results were also presented at the International Image Sensors Workshop 2023.
“Future steps include optimization of this technology in diverse types of thin-film photodiodes, as well as broadening its application on sensors beyond silicon imaging. We are looking forward to further these innovations in collaborations with industry partners,” Malinowski added.
This new technology has potential advantages for detecting infrared light in cameras in autonomous vehicles for seeing through fog or smoke as well as cameras for unlocking smartphones though facial recognition.
Imec has demonstrated the first of its kind incorporation of a pinned photodiode (PPD) structure in the readout circuit of a thin-film-based image sensor. Imec monolithically hybridized a SWIR quantum-dot photodetector with an indium-gallium-zinc oxide (IGZO) based thin-film transistor into a PPD pixel. This array was then processed on a CMOS readout circuit to form a thin-film SWIR image sensor.
“The phototype 4T image sensor showed a remarkable low read-out noise of 6.1e-, compared to >1000e- for the conventional 3T sensor, demonstrating its superior noise performance. As a result, infrared images can be captured with less noise, distortion or interference, and more accuracy and detail,” said imec project leader Nikolas Papadopoulous.
“At imec, we are at the forefront of bridging the worlds of infrared and imagers, thanks to our combined expertise in the thin-film photodiodes, IGZO, image sensors and thin-film transistors,” said imec program manager Pawel Malinowski. “By achieving this milestone, we surpassed current pixel architectural limitations and demonstrated a way to combine the best performing quantum-dot SWIR pixel with affordable manufacturing,”
The findings for the project have been published in the August 2023 edition of Nature Electronics ‘Pinned photodiode for monolithic thin-film image sensors.’ The initial results were also presented at the International Image Sensors Workshop 2023.
“Future steps include optimization of this technology in diverse types of thin-film photodiodes, as well as broadening its application on sensors beyond silicon imaging. We are looking forward to further these innovations in collaborations with industry partners,” Malinowski added.