April 2, 2000 

Energy Conversion Devices, Inc. (ECD) has developed a microelectronics memory technology called Ovonic Unified Memory (OUM) which utilizes unique thin film materials to store information economically and with excellent solid state memory properties. The thin film material is a phase change chalcogenide alloy similar to the film used to store information on commercial CD RW and DVD-RAM optical disks, all based on ECD proprietary technology.

 

Optical memory disks use laser light to write small spots by converting the thin film back and forth from amorphous (disordered atomic structure) to crystalline (regular, highly repetitive, and ordered atomic structure). The digital data of 1's and 0's is stored as amorphous (high resistance and non-reflective) or crystalline (low resistance and reflective) structures. OUM devices store data in a similar manner but use electrical energy controlled by small transistors to electronically convert the material to crystalline or to amorphous (thus a 1 or a 0). This electronic solid state memory stores data in a much smaller area and with higher speeds for both read and write than its optical counterpart.

Ternary Phase Diagram of a Typical Phase Change Alloy

The OUM solid state memory has cost advantages over conventional solid state memories such as DRAM or Flash due to its thin film nature, very small active storage media, and simple device structure. OUM requires fewer steps in an IC manufacturing process resulting in reduced cycle times, fewer defects, and greater manufacturing flexibility. Smaller storage area and cell volume result in smaller die sizes without the increasingly exaggerated topologies, thus producing more memory circuits per wafer with a process that deviates little from a basic CMOS logic flow.

The performance of the OUM memory cell provides for near ideal memory properties. The memory storage is non-volatile (information is retained without power applied). A computer utilizing OUM could be turned off, then turned back on immediately or 10 years later and start right up where one left off. These OUM computers would not be subject to critical data loss when the system hangs up or when power is abruptly lost as are present day computers using DRAM a/o SRAM. With "instant on" operation, OUM computer users would not have to wait for the system to boot up and reload DRAM (presently several minutes are required after power-on where nothing useful is done). Using an OUM memory with no power required to maintain memory while operating or in standby provides substantial competitive advantages for portable applications where battery size and operating time between charging are key competitive metrics.

 

Adding to the cell's attractiveness, the operating speed of OUM memory technology is similar to DRAM and many orders of magnitude faster than Flash write. Also, unlike conventional Flash memory, the OUM memory is fully random accessible for memory addressing. Any given bit can be uniquely addressed, and then written or read by the customer. Further, Flash memory "wears out" (fails) after 100,000 write cycles, while the OUM memory state can be written greater than 10 trillion times, making this memory useful for program storage (Flash) as well as general purpose interactive (DRAM) data storage memory.

The small size, flat topology, and low voltage operation make OUM memory technology highly scalable to smaller geometries. Cell performance improves with shrinking, avoiding many of the scaling barriers arising in conventional charge-based DRAM and Flash technologies. For example, DRAM-based memories need a fixed amount of surface area to store the necessary amount of charge, resulting in undesirable tall skinny structures like a city skyline. This radical topography adds cost, complexity, and cycle time to a conventional DRAM memory process. Also enabling shrinking, the OUM memory provides higher speed active read current from its thin film memory media, avoiding the fixed charge read approach of a DRAM with related test, noise, and soft-error problems.

OUM has direct application in all products presently using solid state memory. These would include computers (desktop, laptop, and palm), cell phones, graphics-3D rendering, GPS, video conferencing, multi-media, Internet networking and interfacing, entertainment, digital TV, telecom, PDA, digital voice recorders, modems, DVD, networking (ATM), Ethernet, and pagers. Further, the relatively simple cell structure and process with its advantageous memory properties make this technology well suited for providing embedded memory on logic IC's where on-board memory can provide significant product performance advantages. OUM offers a way to realize full system-on-a-chip capability through integrating unified memory, linear, and logic on the same silicon chip.

The Ovonic Phase Change Memory Technology is based on original inventions by S. R. Ovshinsky that have been developed at Energy Conversion Devices, Inc., beginning in the 1970s. The history of this work has been described by Memoires Optiques et Systemes magazine.

Phase change memory devices store information through a reversible change in the atomic structure of thin-film alloy materials. Rewrite-able optical memory disks using the technology now are being manufactured under license from ECD in several different form factors using several different data formats. Rewrite-able 650 MB PD and CD-RW format disks are available from many manufacturers, and very high data-capacity, rewrite-able DVD-RAM disks were introduced by ECD's licensees in late 1998. Phase change semiconductor memory devices (Ovonic Unified Memory) with the capability to replace Flash, DRAM, and SRAM chips now are now being developed at ECD.

Energy Conversion Devices, Inc. is a materials-based high technology company located in Troy, Michigan. ECD has pioneered the development and commercialization of product applications and advanced manufacturing processes primarily in the fields of Energy and Information.

 

OVONYX RECEIVES INVESTMENT FROM INTEL 
COMPANIES TO WORK TOGETHER ON MEMORY TECHNOLOGY

TROY, Mich., February 8, 2000 – Ovonyx, Inc., a semiconductor memory technology developer, announced today that Intel Capital has invested in the company. Ovonyx is a joint venture with Energy Conversion Devices, Inc. ("ECD") (NASDAQ:ENER). Financial terms were not disclosed.

Ovonyx is developing phase-change semiconductor memory devices, termed Ovonic Unified Memory (OUM). OUM memory technology promises to enable significantly faster write and erase speeds and higher cycling endurance than conventional memory types. It has been used in rewritable CD and DVD discs and may have potential as a replacement for such memory types as Flash, SRAM and DRAM.

Ovonyx also announced it has licensed its OUM memory technology to Intel and that the two companies will work together to develop and demonstrate the feasibility of high-density, non-volatile memory based on the technology.

"The investment will be used to further the strategic goals of Ovonyx, principally by supporting ongoing development activities," said Tyler Lowrey, CEO of Ovonyx. "These goals include product development to exploit the phase-change technology in the nonvolatile memory and embedded memory/logic marketplace and continuing to expand our patent position."

"Intel continuously develops and fosters technology that has the potential to improve the computing experience. We believe that innovations in materials will enable us to take silicon devices beyond perceived scaling limits for the continued rapid advancement of the digital world," said Dr. Sunlin Chou, Vice President and General Manager, Technology and Manufacturing Group, Intel Corporation.

"I am very pleased that Intel and Ovonyx have established this relationship," said Stanford R. Ovshinsky, President and CEO of Energy Conversion Devices, Inc. and original inventor of the phase-change memory process. "This is a great opportunity for the phase-change memory technology to be widely commercialized in semiconductor applications."

About Ovonyx 

Ovonyx is a joint venture between Tyler Lowrey, former Chief Technical Officer and Chief Operating Officer of Micron Technology, and ECD. It was formed to commercialize semiconductor memory applications of the proprietary phase-change technology originally developed by ECD. Ovonyx nonvolatile memory technology can offer significantly faster write and erase speeds and higher cycling endurance than conventional Flash memory. It also has the advantage of a simple fabrication process that allows the design of semiconductor chips with embedded nonvolatile memory using only a few additional mask steps. Additional information about Ovonyx and its memory technology is available at www.ovonyx.com.