Sony Semiconductor Solutions Corporation (“Sony“) has succeeded in growing the world’s first stacked CMOS picture sensor know-how with 2-Layer Transistor Pixel. Whereas typical CMOS picture sensors’ photodiodes and pixel transistors occupy the identical substrate, Sony’s new know-how separates photodiodes and pixel transistors on completely different substrate layers. This new structure roughly doubles saturation sign stage relative to standard picture sensors, widens dynamic vary and reduces noise, thereby considerably bettering imaging properties. The new know-how’s pixel construction will allow pixels to keep up or enhance their current properties at not solely present but in addition smaller pixel sizes.
Sony introduced this breakthrough on the IEEE International Electron Devices Meeting that began on Saturday, December 11, 2021.
Cross-section picture of CMOS picture sensor with 2-Layer Transistor Pixel know-how
A stacked CMOS picture sensor adopts a stacked construction consisting of a pixel chip made up of back-illuminated pixels stacked atop a logic chip the place sign processing circuits are shaped. Within the pixel chip, photodiodes for changing gentle to electrical alerts, and pixel transistors for controlling the alerts are located alongside one another on the identical layer. Increasing saturation sign stage inside form-factor constraints performs an necessary function in realizing excessive picture high quality with huge dynamic vary.
Sony’s new structure is an development in stacked CMOS picture sensor know-how. Using its proprietary stacking know-how, Sony packaged the photodiodes and pixel transistors on separate substrates stacked one atop the opposite.
In typical stacked CMOS picture sensors, against this, the photodiodes and pixel transistors sit alongside one another on the identical substrate. The new stacking know-how allows adoption of architectures that enable the photodiode and pixel transistor layers to every be optimized, thereby roughly doubling saturation sign stage relative to standard picture sensors and, in flip, widening dynamic vary.
Additionally, as a result of pixel transistors aside from switch gates (TRG), together with reset transistors (RST), choose transistors (SEL) and amp transistors (AMP), occupy a photodiode-free layer, the amp transistors will be elevated in measurement. By rising amp transistor measurement, Sony succeeded in considerably decreasing the noise to which nighttime and different dark-location photographs are susceptible.
The widened dynamic vary and noise discount out there from this new know-how will stop underexposure and overexposure in settings with a mixture of shiny and dim illumination (e.g., backlit settings) and allow high-quality, low-noise photographs even in low-light (e.g., indoor, nighttime) settings.
Sony will contribute to the belief of more and more high-quality imaging corresponding to smartphone images with its 2-Layer Transistor Pixel know-how.
