Image Sensors Boast 1.1-Micron Pixel Size with 2nd-Gen BSI

OmniVision’s second-generation backside illumination image sensors have achieved a 1.1-micron pixel size, enabling smaller sensors with better sensitivity.

By Cliff Roth

Page 1 of 1
Video/Imaging DesignWire
(2/12/2010 3:27:55 AM)

OmniVision Technologies announced the introduction of the world’s first 1.1-micron backside illumination (BSI) pixel. The new OmniBSI-2TM pixel architecture represents a milestone in digital imaging technology, OmniVision says, enabling new imaging solutions with superior image quality and low-light sensitivity. The architecture also extends OmniVision’s pixel roadmap to sub-micron levels, and serves as a key enabler in the continuous miniaturization of digital imaging technology.

“OmniBSI-2 drives the development of higher resolution image sensor solutions with an aggressive form factor and lower z-height for ultra-thin products,” said Bruce Weyer, vice president of worldwide marketing at OmniVision. “OmniBSI-2 advances the digital imaging market by enabling improved image quality and enhanced low-light performance that dramatically improves the user experience in video-based applications. OmniBSI-2 technology can also be applied to larger pixel designs to achieve performance advantages that exceed current BSI and FSI imaging sensors.”

OmniBSI-2 is OmniVision’s second-generation BSI technology, and is the first pixel built on a 300-mm copper process at 65 nm design rules developed in cooperation with strategic manufacturing partner, Taiwan Semiconductor Manufacturing Company Limited (TSMC). By combining custom 65 nm design rules and new manufacturing process modules, the 1.1-micron OmniBSI-2 pixel achieves industry-leading low-light sensitivity as well as significantly improved dark current and full-well capacity. OmniBSI-2’s custom pixel design rules also enable better pixel layout, better isolation, and significantly reduced crosstalk. Each of these advances represents a substantial improvement over the first generation OmniBSITM technology resulting in better image quality, enhanced color reproduction and improved camera performance.

“By comparison, the new 1.1-micron OmniBSI-2 pixel not only outperforms our current 1.75-micron FSI architecture, but it also equals the performance of our industry-leading 1.4-micron BSI pixel that is currently in mass production,” commented Dr. Howard Rhodes, vice president of process engineering at OmniVision. “Migrating to 1.1-micron BSI pixel architecture required moving production to TSMC’s state-of-the-art 300-mm copper process, which enabled substantially improved design rules and more advanced process tools, resulting in tighter process control and improved defect density. Key to our success was the joint development by the OmniVision and TSMC R&D teams of multiple new process modules that substantially improved opto-electronic performance.  We also leveraged our close partnership with joint venture partner VisEra Technologies to establish a 300-mm color filter fabrication capability.”

“OmniVision and TSMC have been long standing partners in CMOS Image Sensor development. Our engineering teams collaboratively push the boundaries of digital imaging, making them an excellent development and manufacturing partner,” said Sajiv Dalal, vice president, business management at TSMC North America. “OmniVision’s product migration to 300-mm manufacturing will give it a clear competitive edge and we stand committed to continuously drive improved efficiencies to help widen the gap.”

“TSMC has been a valuable partner in making the transition to this advanced process node,” added Dr. Rhodes. “Their experience and expertise in 300-mm processing at the advanced technology nodes and ability to continue enhancing the sensor performance have been invaluable in ramping this new pixel technology so quickly and seamlessly.”

OmniBSI and OmniBSI-2 adopt a radically advanced approach to traditional pixel architectures. OmniBSI technology involves turning the image sensor upside down and applying color filters and micro lenses to the backside of the pixel so that light is collected through the backside of the sensor. It effectively reverses the arrangement of layers so that metal and dielectric layers reside below the sensor array, providing the most direct path for light to travel into the pixel, which optimizes the fill factor to deliver best-in-class low-light sensitivity, image quality and color reproduction.

OmniBSI technologies also provide the basis for future CIS architectures, the company says, by enabling continued improvements in sensitivity, color reproduction and image quality while continuing to reduce designs down to 0.9-micron pixels and beyond.

OmniVision’s new OmniBSI-2 technology will be demonstrated to customers by appointment at the Mobile World Congress, February 15 through 18, 2010 in Barcelona, Spain.

For more information, visit