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IP Start-Up Develops High Density Vertical Flash Memory

BeSang Demonstrates 10 K-Bit Flash Memory Array

PORTLAND, Ore., Jan. 25 /PRNewswire/ -- BeSang Inc., a fabless start-up semiconductor IP company based in Portland, OR, has successfully demonstrated its multi-bit vertical flash memory technology. Combining a 4F2 physical memory cell area and 2-bit per cell memory technology, the flash memory has 2F2 cell density, where "F" refers to the minimum device feature size. BeSang's single-chip 3 dimensional ("3D") integrated circuit ("IC") technology will produce four times more die per wafer than conventional layout because the high density memory cells are placed on top of a memory control logic wafer, making the effective NOR flash memory cell size 0.5F2 when the multi-bit vertical flash memory array is implemented with BeSang's 3D IC.

"BeSang's vertical flash memory has been designed and developed to be implemented using BeSang's proprietary single-chip 3D IC since the 3D IC is more efficient with vertical than planar devices," said Sang-Yun Lee, CEO of BeSang. "BeSang expects that a 0.5F2 effective cell size will change the rules of the game in the flash memory market because it is 8 times smaller than conventional 4F2 NOR flash memory cell technologies currently available. The effective memory cell size can be further reduced to 0.12F2, which is about 32 times smaller than conventional NOR cell, using stacked-SGT ("Surround Gate Transistor") and double memory layers."

The vertical flash memory cell is based on well-known SGT technology and uses single crystalline silicon material. Conventional CMOS tools, materials, and CMOS processes are used to implement the high density vertical flash memory, providing an added advantage.

"BeSang's 3D technology is very significance because it is a novel combination of well-known CMOS process and device technologies. Many other emerging technologies were not successful in commercialization because they were based on new materials and new device concepts and CMOS fabs have little accumulated experience in manufacturing these emerging technologies. Hence, conventional CMOS technology has prevailed in the market for decades even though advanced CMOS technology is becoming less and less affordable," said Dieter K. Schroder, Professor at Arizona State University.

Conventional 3D chip technologies are merely package-level multi-chip stacking technologies with limited mobile applications. The technology developed by BeSang allows vertical memory cells to be stacked on top of conventional CMOS logic within a semiconductor chip, using seamless and unlimited interconnects between device layers. As a result, this single-chip, high-density 3D technology provides the semiconductor industry with a low- cost, high-performance vertical memory solution.

About BeSang. BeSang is a fabless semiconductor IP company providing its proprietary 3D Enabling Technology. The Company is entering the semiconductor memory business for both stand-alone and embedded memory markets. The main mission of the Company is to provide unique "Single-Chip 3D" enabling solutions that can significantly reduce die cost of semiconductor chips, including ultra high density memories and high quantum efficiency image sensors. For more information, see BeSang's Website at http://www.besang.com/ .