LONDON – The Shanghai Institute of Microsystem and Information Technology (SIMIT) at the Chinese Academy of Sciences – working with foundry chipmaker SMIC and Microchip Technology – has announced it has developed phase-change random access memory (PCRAM) that is based on Chinese intellectual property, according to a Xinhua report.
The 8-Mbit memory, scheduled for mass production later this year, is intended for use as a replacement for NOR flash in applications such as mobile storage and RFID, according to Chinese language reports in translation. It is relatively modest in capacity, compared with available flash memory but for China the development is intended to break the foreign control of memory chip production and has been accompanied by the filing of about 200 patents, the reports said.
The PCRAM was manufactured jointly by Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences, Semiconductor Manufacturing International Corp. and Microchip Technology Inc., according to Xinhua, the official press agency of the government of the People's Republic of China. No details were provided of the geometry of the manufacturing process or plans to scale the manufacturing or produce devices with increased capacity.
While it is expected that SMIC could act as a foundry manufacturer of the relatively modestly sized memory it is not yet clear what the role of Microchip (Chandler, Arizona) is in the development of the memory.
Phase-change memory – like NOR and NAND flash – is nonvolatile, providing power-saving opportunties. Its operation is conventionally based on the change of resistance as a chalcogenide glass changes state from amorphous to crystalline under the heating effect of a current passing through a thin film. Although theoretically superior to DRAM, SRAM and flash memory on a number of counts it has yet to reach mainstream commercial adoption.
Micron and Samsung are in the lead. Samsung has developed a 512-Mbit PCRAM test chip on a 60- to 65-nm manufacturing process which has achieved some deployment in Samsung mobile phone. Micron, through its Numonyx acquisition has a 128-Mbit device on 90-nm process. Numonyx was also working on a 1-Gbit phase-change memory on a 45-nm process.
The Shanhai Institute's PCRAM test chip was made on 200-mm diameter wafers but details of the manufacturing process technology or whether it is based on chalcogenide material were not discussed in Chinese language reports.
A voice demonstration has confirmed that the chip can read, write and erase, according to Xinhua. The patents cover technologies ranging from the distribution of materials, structures and chip design to means of testing. China plans to be able to supply 60 percent of its own memory IC requirements within 10 years.
Related links and articles:
Samsung CEO: Headwinds hinder PRAM
Update: PCM found in handset
CTO confirms IBM's PCM expectations
A series of articles on PCM authored by Ron Neale and published in EE Times Memory Design Line:
PCM Progress: Temperatures rise and constituents on the move
PCM The Myth of Scalability Part 3- Is WAL-PCM the salvation?
PCM Scalability:The Myth (Part 2)
PCM scalability--Myth or realistic device projection (Part 1)