Samsung's Image Sensor Counteroffensive: Can 500MP and Three-Layer Stacking Technology Shake Sony's Dominance?

Samsung's Image Sensor Counteroffensive: Can 500MP and Three-Layer Stacking Technology Shake Sony's Dominance?Sony Semiconductor has long held a dominant position in the mobile phone camera sensor market. A series of flagship products, including the IMX766, IMX700, IMX890, IMX989, LYT-818, and LYT-900, have made it the preferred supplier for numerous flagship smartphones

Samsung's Image Sensor Counteroffensive: Can 500MP and Three-Layer Stacking Technology Shake Sony's Dominance?

Sony Semiconductor has long held a dominant position in the mobile phone camera sensor market. A series of flagship products, including the IMX766, IMX700, IMX890, IMX989, LYT-818, and LYT-900, have made it the preferred supplier for numerous flagship smartphones. However, the rise of Chinese manufacturers in recent years has presented a challenge to Sony. Meanwhile, Samsung, once a sensor giant, faces even more severe challenges. A few years ago, Samsung enjoyed great success with its large-sensor technology, such as the GN2 used in the Xiaomi 11 Ultra's main camera. But today, its presence in the high-end image sensor market has significantly diminished, except for its own phones and some telephoto sensor applications.

However, Samsung hasn't given up the fight. Sources reveal that Samsung is diligently developing two new image sensor technologies, aiming to break Sony's monopoly and seize a larger market share. What makes these technologies so special? Let's delve deeper.

01. Targeting Apple: Samsung Challenges Sony's Exclusive Supply Status

In July 2023, rumors circulated that Samsung had become Apple's second image sensor supplier. Reports suggested that production issues at Sony, potentially delaying the iPhone 15 launch, forced Apple to diversify its supply chain and begin testing Samsung's sensors. Analyst Ming-Chi Kuo also predicted that Samsung would start supplying Apple with 48MP ultra-wide-angle image sensors as early as 2026, even forming a dedicated team to serve Apple.

These reports sparked widespread debate, with many questioning their veracity. After all, Apple has favored Sony's sensors since the iPhone 6, and CEO Tim Cook publicly affirmed the decade-long partnership during a visit to Sony in 2022. However, a recent leak adds credence to the possibility of Samsung breaking Sony's exclusive supply to Apple.

On January 1st, leaker @Jukanlosreve on X (formerly Twitter) stated that Samsung is developing a new sensor for Apple, featuring a three-layer stacked design with a "PD-TR-Logic configuration," claiming it outperforms Sony's Exmor RS series.

The emergence of three-layer stacked sensor technology represents a significant advancement in image sensor technology. Let's review traditional sensors and Sony's two-layer stacked technology.

02. In-depth Analysis of Three-Layer Stacked Sensor Technology

In traditional sensor structures, photodiodes and pixel transistors are located on the same substrate, with a backside-illuminated pixel chip stacked on top of the logic chip. This structure has two major drawbacks: a large footprint and a long pixel value transmission distance, affecting imaging speed and quality, making it difficult to achieve high dynamic range and high image quality. In short, the components are laid out flat, resulting in long signal transmission paths and low efficiency.

Sony's two-layer stacked technology encapsulates photodiodes and pixel transistors on separate substrates, enabling stacking. This design allows for independent optimization of the photodiode and pixel transistor layers, approximately doubling the saturation signal, thus expanding the dynamic range. Furthermore, by increasing the size of the amplifying transistors, image noise in low-light environments can be effectively reduced. The first layer (photodiodes) handles photoelectric conversion, while the second layer (pixel transistors) handles signal processing. Their collaboration captures more light, reduces noise, and avoids underexposure or overexposure in mixed lighting conditions, resulting in high-quality, low-noise images even in low-light environments.

Three-layer stacked sensors go further. As the name suggests, they stack three chips in a "sandwich" configuration. While the exact stacking method remains unclear, the advantages are obvious. Stacked sensors inherently shorten pixel value transmission distances and improve processing speed, and three-layer stacking amplifies this advantage, allowing signals to be converted into images faster, supporting higher demands for burst shooting and imaging speed.

As early as 2017, Sony launched the industry's first three-layer stacked CMOS image sensor with DRAM, but it didn't see widespread adoption. While boasting impressive specifications on paperreading a 19.3MP still image at 1/120th of a second and achieving a 1000fps frame rate in video modeits use in a few Sony models didn't lead to broader implementation.

03. The Impact and Challenges of a 500MP Sensor

Besides the three-layer stacked sensor for Apple, @Jukanlosreve also revealed that Samsung is mass-producing another three-layer stacked sensor for its future Galaxy flagship line, boasting an astounding 500-megapixel count.

Most current flagship phones use main cameras with around 48MP or 50MP. Cameras exceeding 100MP are rare, often found in lower-end models using pixel count as a marketing gimmick. The Samsung S24 Ultra uses its own 200MP ISOCELL HP2 sensor, and the S25 Ultra is rumored to continue using it.

While the market once debated the merits of 100MP phones, the emergence of 500MP renders them comparatively insignificant. Many believe high megapixels equate to high image quality, but this is a misconception. High resolution does bring more detail, but it also leads to smaller individual pixel sizes, increased light sensitivity requirements, noise, and over-sharpening. The final image quality depends on sensor size, aperture, lens quality, ISP performance, and software algorithms. Judging camera performance solely on megapixel count is inaccurate.

Information on Samsung's 500MP sensor is currently limited, and its mass production and final image quality remain to be seen, with an expected debut in the S26 Ultra.

04. Can Samsung Seize Victory from Sony?

Samsung's 500MP sensor and three-layer stacking technology represent a strong challenge to both Apple and Sony. In the current flagship market, Sony dominates the main camera sensor segment, followed by Chinese manufacturers, with Samsung lagging behind. To catch up, Samsung needs to demonstrate exceptional capabilities.

Samsung's targeting of Apple is clear. Successfully replacing Sony as Apple's supplier would be a significant validation of Samsung's capabilities. Whether Samsung can change Apple's long-standing preference for Sony may be revealed next year. Samsung's counteroffensive promises to bring significant changes to the mobile image sensor market. We wait with bated breath.