At its Kumamoto Plant (Tamana, Kumamoto Prefecture, Japan), Toppan Printing Co., Ltd. (hereafter Toppan Printing; Head office: Chiyoda Ward, Tokyo; President & CEO: Naoki Adachi) has constructed a production line for color filter arrays (CFAs) (*1) for image sensors (*2) that can be formed on 12 inch wafers. Full operation will commence in late July 2009.
With the enhancement of the production line, Toppan Printing will be able to respond to the demand for cutting-edge 12 inch wafers and its total production capacity, including overseas production (*3) and the existing wafer-level production, will improve around 20% to 45,000 wafers per month (8 inch wafer equivalent).

An image sensor is a photoelectric conversion element that converts light volume into an electric signal. It is an indispensable component of digital cameras and cameras on mobile phones for converting the light taken in by the lens into digital data. Typical examples are CCD and CMOS sensors.
A CFA is a component where a color filter for color separation and a micro-lens array (*4) for enhancing light condensing efficiency are formed by layering directly on a light sensitive element (phototransistor) formed on a silicon wafer. It is an essential component for determining the color of the digital data taken in by the image sensor. Toppan Printing receives silicon wafers with phototransistors formed on them from image sensor manufacturers and forms CFAs on the wafer.
Toppan has constructed a production line to correspond to leading-edge 12 inch products and is aiming for the further expansion of its business.

Background
Image sensors are used in items such as mobile phones with cameras, digital cameras, and cameras mounted in automobiles, and expansion of the market is anticipated in the future.
As digital image devices become smaller and their image quality improves, needs in the market are becoming more sophisticated, which requires finer fabrication and higher functionality for image sensors. Therefore, semiconductor manufacturers have begun production using 12 inch wafers in order to take advantage of advanced technologies to make components finer (higher definition) and increase efficiency in producing image sensors for cutting-edge digital devices.
In order to respond to this demand, Toppan Printing has built a new production line to correspond to 12 inch wafers at its Kumamoto Plant.

Future target
Toppan Printing will proceed with the development of CFAs that have high definition and functionality, and will aim for the further expansion of the business.


*1 Color filter array:
A color filter formed directly on the light sensitive element of an image sensor. Also known as an On-chip color filter.

*2 Image sensor:
This is a sensor that uses a photoelectric conversion element that converts light volume into an electric signal.
It is comprised of many small elements called pixels. A single pixel consists of a light sensitive element and a transfer component. The light sensitive element receives light, and the element responds to generate an electric signal. However, since the element only responds to light and dark, on its own it cannot record a color image. Therefore CFAs are formed on the light sensitive element, and color images are taken in by identifying specific light strengths. Typical examples are CCD and CMOS sensors.

*3 Overseas production:
Toppan Printing performs CFA manufacturing and sales at Toppan SMIC Electronics (Shanghai) Co., Ltd. in Shanghai, China.

*4 Micro-lens array:
A lens formed on each pixel of an image sensor. It improves the light condensing efficiency on minute pixels.

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