SeeDevice Announces PAT-PD Smart Vision Sensor With Quantum Tunneling

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PRNewswire, PRNewswire: La Palma, CA-based SeeDevice startup announces the general licensing availability of Photo Assisted Tunneling - Photo Detector (PAT-PD). The agreement allows partners to easily integrate SeeDevice's smart sensing technology into their products.

"PAT-PD uses quantum tunneling to rewrite a lot of the current specifications for light sensors. placing it in an entirely new category of photon sensing capability," said Hooman Dastghaib, CEO of SeeDevice.

PAT-PD is said to expand the CMOS sensors sensitivity beyond visible light all the way into SWIR (300nm-1,600nm band) with plans to expand to 2,000nm with their next-generation sensor, while maintaining low-light and near no-light sensing.

Additionally, the PAT-PD sensor increases photo-sensitivity to 106 A/W with SNR of over 60dB at room temperature. Response time is also reduced from microseconds to sub-nanoseconds while boosting DR to 100dB linear and 150dB non-linear.

SeeDevice achieves these results using standard CMOS fabrication process allowing for easy integration in mixed-signal process and avoiding expensive exotic materials and manufacturing processes to achieve similar results.

Current photo sensors work by directing incoming light to an array of PDs and photo-transistors that convert the light into an electric current which is amplified and then converted into viewable pixels using software. Image sensors using PDs are said to requir as much light as possible to generate a high-quality image so, unless pictures are taken in bright sunlight or perfect indoor lighting conditions, image quality degrades significantly in lower-light conditions. Sensitivity of PDs is said to be measured in uV per electron generated or amps/watt (A/W). While typical photo-diode sensors generate 0.15-0.25 A/W, PAT-PD uses quantum tunneling to produce an astounding 108 A/W, surpassing the performance of today's leading CMOS image sensors.

Quantum tunneling allows a photon-activated current flow to trigger using a fraction of the photons normally required in a photo-diode-based design. This allows the PAT-PD sensor to trigger with just a single photon, generating a current with unprecedented efficiency and creating a signal with significantly less input over a far wider range of wavelengths. Using a PAT-PD silicon-based CMOS image sensor, devices will be able to convey granular-level sharp details, even in extremely low light conditions, utilizing infrared, near infrared, and short-wave infrared frequencies.

According to Google, SeeDevice has filed for 8 patents so far, 5 of them are granted. The most recent out of published applications, the US20190237611, talks about strained silicon layers that expand the sensitivity into IR:

"Here, the wavelength expanding layer is formed including strained silicon and can split the energy levels of the conduction band and the valence band according to the direction of the crystal lattice planes of silicon.

Here, the light-receiving element can include a plurality of the wavelength expanding layers, which are different from each other in terms of at least one of their formation location and manufacturing process.

Here, the wavelength expanding layer can be formed by applying stress onto silicon and the interface of the oxide film.

Here, the wavelength expanding layer is formed including strained silicon and can split the energy levels of the conduction band and the valence band according to the direction of crystal lattice planes of silicon.

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