Semicon West, July 1999….IMEC, Europe’s leading microelectronics research center, has developed a dedicated, highly efficient, non-volatile memory cell compatible with standard 0.35mm CMOS processes.

IMEC’s patented HIMOSâ (High Injection MOS) cell, based on source-side injection, offers very high programming speeds at moderate voltages and power consumption, with low development entry cost, leading to a truly embedded memory processing module that can be combined with any standard CMOS process.  In contrast with other non-volatile processes where many additional processing steps are required to embed the cell in a standard CMOS process, this cell requires the addition of only four masking steps.

Several cell layouts were used in a 1 Mbit flash EEPROM memory in order to validate the HIMOS® concept in a 0.35 mm CMOS process. The smallest cell size, used without compromising low voltage, is 3.5 mm2.

Voltage is kept to a low 3.3V by the use of a highly efficient source-side injection technique.

Typical programming time is about 1µs, while full array programming requires 5-10µs.   Erasing is done with –6V on the gates and 3.3V on the drain, or, alternatively, with –5V on the gates and 4.5V on the drain, using a small bitline charge pump. The number of write/erase cycles is specified at 100,000 without need for adaptive erasing techniques, sacrificial programming cycles, or program/erase verify. This makes the cell of practical use for both code and data storage applications.   The cell may also be adapted to a byte-erasable version which could easily compete with full-feature EEPROMs, while allowing much larger densities. The read-disturb characteristics after cycling are valid for 10 years’ continuous read-out after 100,000 write/erase cycles in contrast to some other technologies that are qualified only in terms of the  number of read cycles.

IMEC is currently developing a 0.25µm version of the cell, which is expected to look very much like the 0.35µm version. Early results indicate that the cell can be easily scaled down to less than 2µm2, while using the same process concept. Alternative versions are under investigation allowing a cell size of somewhat more than 1µm2 at the expense of somewhat lower performance and/or added processing complexity.

“With the knowledge base IMEC has built up in developing low-cost embedded non-volatile memory CMOS-based technologies, it is well placed to help semiconductor companies to integrate the HIMOS concept in their CMOS based process,” comments Dr. Ludo Deferm, Associate Vice President of Silicon Technology and Device Integration.

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Notes to editors

ABOUT IMEC

IMEC was founded in 1984 and is today Europe’s leading independent research centre for the development and licensing of state-of-the-art microelectronic technologies.  IMEC is headquartered in Leuven, Belgium and employs about  850 people, of whom 75 % are highly qualified scientists and engineers. Its $ 88million revenue is derived from agreements and contracts with government agencies, aerospace and semiconductor industry companies world-wide.

IMEC’s activities  concentrate on: design of integrated information and communication systems (System on Chip, MPEG-4, Broadband wireless modems); silicon  process technology (lithography, Cu & low k back end, salicides, clean, dry etch, pilot line); silicon technology and device integration (deep submicron CMOS, BICMOS, NVM, reliability, analysis); microsystems, components and packaging (packaging, optoelectronic components, imagers, smart sensors and integrated microsystems, solar cells); training center for advanced training in microelectronics (including IC design, process technology and packaging).

For further information please contact:

Marianne Van den Broeck

Head of Public Relations

IMEC, Kapeldreef 75

B- 3001 Leuven, Belgium

http://www.imec.be

Tel +32 16 28 14 91

Fax +32 16 28 16 37

Email: Marianne.vandenbroeck@imec.be