The CMOS image sensor (CIS), known as the “electronic eye,” is a rare device among a variety of semiconductors because its market size continues to expand. Shipment volume in 2021 is estimated to have increased by 10% year-on-year to 8 billion units.

In addition to smartphones, which saw an increase in shipments of 5G (5th generation mobile communication system) models, sales for PC peripherals such as mobile cameras were also strong due to the spread of remote work. Demand is expected to increase in industrial applications such as in automobiles, surveillance cameras, and inspections. There is no sign of market growth stopping anytime soon.

Sony Group Corp. holds the world’s top share of roughly 50% in the image sensor market. The company achieved an 8.6% increase in sales of image sensors from the previous year to 947.3 billion JPY in FY2021 (ending March 2022), as it approaches the 1-trillion-yen milestone. Sales for mainstay smartphones are expected to be lower than initially anticipated due to a slowdown in the upward trend for the number of sensors installed per unit and the slump in the Chinese market.

Meanwhile, the increase in applications in digital cameras and industrial goods, and the trend for bigger sensors are expected to contribute positively. The company has set a goal of achieving a 60% global market share in FY2025 and has resumed investment to increase production, which had been temporarily restrained due to the suspension of shipments to China’s Huawei Technologies Co. on the back of trade friction that emerged in 2020 between the U.S. and China.

According to Sony’s mid-term plan for FY2021-23, the company will invest 900 billion JPY in semiconductors out of 1.5 trillion JPY in total investment and loans. In addition to its plan to increase production capacity by sequentially introducing manufacturing equipment at “Fab5” which was opened at the company’s Nagasaki Technology Center in Isahaya City, Nagasaki Prefecture in April 2021, Sony plans to invest 500 million dollars (c. 57 billion JPY) in the semiconductor foundry that TSMC plans to build in Kumamoto Prefecture, aiming to strengthen its cooperation with the Taiwanese manufacture.

Sony has long been outsourcing to TSMC the production of logic semiconductors, which are indispensable for stacked image sensors. By investing in the new Kumamoto factory, it looks to build a system that will secure procurement of the chips in the face of semiconductor shortages. The new TSMC Kumamoto factory is scheduled to start operations before the end of 2024.

Test Run in Rome

In recent years, Sony has been focused on expanding the range of applications of its sensors not only in “imaging” applications (i.e. taking photos and videos) but also in sensing applications (i.e. autonomous driving and industrial inspection.) It wants to not merely sell devices but establish a recurring business through services that will generate stable and long-term profits for the company.

As part of such an effort, Sony has been actively launching new products such as Time of Flight (ToF) image sensor that can accurately measure the distance to the target object and the Event-based Vision Sensor (EVS) that can visualize the trajectory of the event (such as throwing a ball).

Sony also announced the start of a new service Aitrios in September 2021, which is expected to play a major role in the advancement of the field of sensing. The service allows users to utilize various data acquired from Sony’s intelligent vision sensor “IMX500” equipped with AI (artificial intelligence) processing function.

The service promotes digital transformation in various scenes such as smart cities, smart retail, smart buildings, AR (augmented reality) and entertainment, and smart factories. Sony is looking for a wide range of partner companies to develop and introduce sensing solutions using AI cameras and other technologies.

For example, Sony is taking part in a trial run of a smart city in Rome, Italy, using camera systems. The project uses a smart parking system that automatically determines the vacancy of a parking lot and an operation optimization solution that detects in advance the congestion of bus stops. In addition, Sony is targeting retail customers in Japan to provide new experiences using AI cameras, such as inventory detection at food corners.

Fierce Competition with Samsung

Sony’s biggest rival in the image sensor market is South Korea’s Samsung Electronics Co., which ranks second in the semiconductor market. Samsung has effectively gained the second largest market share in image sensors for high-end smartphones after Sony.

It is reportedly aiming to increase its monthly production capacity by about 10,000 sheets annually and is second only to Sony. Image sensor sales in 2020 are estimated to be about 4.6 trillion won (c. 440 billion JPY) and are expected to grow to 5.5 trillion won in 2021. Samsung, whose strength is in the production of logic semiconductors, is leading Sony in high-resolution image sensors by using ultrafine pixel technologies.  In 2020, ahead of Sony, it succeeded in mass-producing a 108-megapixel image sensor that achieved a pixel size of 0.7 micrometers.

Subsequently, in 2021, Samsung launched an image sensor that achieved 200 megapixels by refining it to 0.64 micrometers. It has set a goal of increasing the number of pixels to about 600 megapixels and bringing the performance as close as possible to the human eye by 2025. It is determined to beat Sony.

Sony isn’t making it easy for Samsung either. In December 2021, Sony announced that it developed the world’s first stacked CMOS image sensor with two-layer transistor pixel technology, which could greatly improve imaging properties.

The image sensor which adopted a new structure separates photodiodes and pixel transistors on different substrate layers. The new technology realized a wider dynamic range (the range of brightness that can be identified by the camera in one shot) and reduced noise, enabling high-quality shooting without overexposure or underexposure even in scenes with a large difference in brightness (i.e., backlit setting), and dark scenes such as indoors and night scenes.

As such, there is much room for image sensors to expand their applications. It is a device that’s performance and functions can be improved without relying solely on miniaturization, so companies can engage in technological competition regardless of the amount of investment or the performance of manufacturing equipment. Even as the competitive environment becomes fiercer over the years, it is still quite possible for Sony to achieve a global market share of 60% or more.

(Akihior Tsumura, Senior Staff Writer and Vice President at the Editorial Department at Sangyo Times)