Backside Illumination Technology Improves Image Quality, Enables Design Shrinks Down to 0.9 Micron Pixels SUNNYVALE, Calif., May 27
SUNNYVALE, Calif., May 27 /PRNewswire-FirstCall/ -- OmniVision
Technologies, Inc. (Nasdaq: OVTI), the world's largest supplier of CMOS image
sensors, today launched its OmniBSITM architecture, a novel sensor design that
adopts a radically different approach to traditional CMOS image sensor
technology. Using backside illumination (BSI), OmniBSI enables OmniVision to
continue offering improved image quality while extending its pixel roadmap
down to 0.9 micron pixels, which is the key to continued miniaturization of
digital imaging technology. OmniVision developed OmniBSI architecture with the
support of its long-time foundry and process technology partner, Taiwan
Semiconductor Manufacturing Corporation (TSMC).
BSI methodology involves turning the CameraChip(TM) sensor upside down so
that it collects light through what was previously the backside of the sensor,
the silicon substrate. This approach differs from conventional front side
illumination (FSI) image sensors, where the amount of light reaching the
photo-sensitive area is limited, in part, by the multiple metal and dielectric
layers required to enable the sensor to convert photons into electrons. The
FSI approach can block or deflect light from reaching the pixel, ultimately
reducing the fill factor and causing additional problems, such as cross talk,
between pixels. BSI reverses the arrangement of layers so that the metal and
dielectric layers reside below the sensor array, providing the most direct
path for light to travel into the pixel. This novel approach optimizes light
absorption, enabling OmniVision to build a 1.4 micron BSI pixel that surpasses
all the performance metrics of 1.4 micron, and even most 1.75 micron, FSI
pixels.
OmniBSI architecture delivers a number of performance improvements over
FSI, including increased sensitivity per unit area, improved quantum
efficiency and reduced cross talk and photo response non-uniformity, which all
lead to significant improvements in image quality. Since light directly
strikes the silicon, the fill factor of the image sensor is significantly
improved so as to deliver best-in-class low-light sensitivity. A much higher
chief ray angle enables shorter lens heights which in turn allows for thinner
camera modules, which are ideal for use in the next generation of ultra-thin
mobile phones. Finally, BSI technology affords a much larger aperture size,
which allows for lower f stops facilitating the development of better
performing camera modules with superior camera performance.
"Moving FSI pixel architectures down to 1.4 micron and below, under
current design rules, poses some real challenges because metal lines and
transistors are driving the aperture of the pixel close to the wavelength of
light, its physical limit," said Howard Rhodes, Vice President of Process
Engineering at OmniVision. "To overcome this with traditional FSI pixel
technology would require a migration to 65 nm copper process technologies,
which would significantly increase the complexity and cost of manufacturing.
Because it allows for more than three layers of metal, BSI achieves
significant manufacturing benefits without moving to smaller process nodes.
This means routing can be simplified and die sizes can be smaller than in FSI
sensors, without the need to move to smaller process nodes with all their
associated complexities and additional costs."
"Although backside illumination concepts have been studied for over 20
years, up until now nobody has been able to successfully develop the process
for commercial, high volume CMOS sensor manufacturing," said Dr. Ken Chen,
Senior Director, Mainstream Technology Marketing, TSMC. "Combining
OmniVision's imaging expertise with TSMC's experience in process development,
we have delivered a truly advanced technology that defines the future of
digital imaging."
"BSI allows OmniVision to further extend its competitive edge in digital
imaging technology, while continuing the use of our production-proven, 0.11
micron process technology. This provides major cost and performance advantages
for OmniVision and, ultimately, our customers," concluded Rhodes.
OmniVision is currently demonstrating an 8 MegaPixel, OmniBSI CameraChip
sensor, and expects to start sampling first products before the end of June.
About OmniVision(R)
OmniVision Technologies designs and markets high-performance semiconductor
image sensors. Its CamerChip(TM) products using OmniPixel(R), OmniPixel2(TM),
OmniPixel3(TM), OmniPixel3-HS(TM) and OmniBSI(TM) technologies are highly
integrated single-chip CMOS image sensors for mass-market consumer and
commercial applications such as mobile phones, digital still cameras, security
and surveillance systems, interactive video games, laptops and PCs and
automotive and medical imaging systems. Additional information is available at
http://www.ovt.com.
Safe-Harbor Language
Certain statements in this press release, including statements regarding
the performance achievements and capabilities of BSI, the advantages that BSI
provides to OmniVision and its customers, the effect of BSI on future digital
imaging and the timing of the release of BSI products, are forward-looking
statements that are subject to risks and uncertainties. These risks and
uncertainties, which could cause the forward-looking statements and
OmniVision's results to differ materially, include, without limitation:
potential errors, design flaws or other problems with BSI; risks associated
with developing future architecture and products incorporating BSI; the rapid
changes in technical requirements for camera phone products; competitive
risks; as well as other risks detailed from time to time in OmniVision's
Securities and Exchange Commission filings and reports, including, but not
limited to, OmniVision's most recent annual report filed on Form 10-K.
OmniVision expressly disclaims any obligation to update information contained
in any forward-looking statement whether as a result of new information,
future events or otherwise.
OmniVision(R), the OmniVision logo and OmniPixel(R) are registered
trademarks of OmniVision Technologies, Inc. CameraChip(TM), OmniPixel2(TM),
OmniPixel3(TM), OmniPixel3-HS(TM) and OmniBSI(TM) are trademarks of OmniVision
Technologies, Inc.
SOURCE OmniVision Technologies, Inc.
