Weebit ReRAM starts to roll at Embedded World
Eight years after its founding in 2015, Weebit Nano Ltd. (Hod Hasharon, Israel) has announced the availability of its resistive RAM (ReRAM) non-volatile memory.
Weebit also expects to announce its next foundry partner before the middle of 2023 but said that the introduction of high capacity, discrete ReRAM using a space-efficient selector switch is still at least two years away.
Weebit’s oxide-based ReRAM is available in the form of IP in the 130nm CMOS manufacturing process of foundry SkyWater Technology Inc. Weebit plans to demonstrate the technology using ReRAM modules at Embedded World, March 14 to 16, and said that customers can now design the memory into ASICs and SoCs as it will be fully supported in the next release of SkyWater’s S130 process design kit (PDK). The SkyWater-produced demo chips have proved fully functional. These chips are currently under qualification, and are being used for customer demonstrations, testing and prototyping.
Weebit has also announced a tape-out of test chips with Globalfoundries on that foundry’s 22nm fully depleted silicon-on-insulator process (see Weebit tapes out ReRAM on 22nm FDSOI process).
Eran Briman, vice president of marketing and business development, said the 130nm process and first ReRAM products provide a good platform for adding non-volatile memory to analog/mixed-signal, IoT, medical, automotive, industrial, and other applications.
TSMC helps us
He added that while some foundries have their own ReRAM offering (see Infineon’s microcontrollers to go RRAM with TSMC) that does not stop them from also offering Weebit Nano’s technology. “We are talking to most of the top ten foundries,” said Briman “The Infineon-TSMC announcement has brought a great deal of interest towards Weebit – not just from foundries but also from IDMs.”
Weebit ReRAM offers 10 years data retention and 10^5 cycling endurance. The manufacturing process is relatively simple compared with embedded flash and other emerging non-volatile memories, being a back-end metal cross-point. This allows for reduced costs and, unlike flash memory, Weebit’s ReRAM has the ability to scale far below 28nm process nodes. Weebit has also been able to demonstrate better than industrial-temperature range robustness and radiation hardness up to 10Mrad, which is far beyond the capability of CMOS access circuits.
However, the use of Weebit’s ReRAM technology to make discrete memory components or chiplets could be a couple of years off, even though chiplet die assembly could start to become pervasive in the industry.
Briman said: “It is going to take at least 24 months before we have a large memory array with a back-end selector.” He added: “We decided strategically to focus on the embedded market. It is lower memory density and we can use a transistor for the selector.” Briman said that for EEPROM and NOR flash replacement ReRAM can be competitive. “Even with a small transistor we can win on die-size versus the competition,” he said. NAND flash and storage-class memory replacement is a longer-term market, he added.
Briman said that progress is being made with a back-end selector and that working with CEA-Leti on the technology brings advantages. But he also said it does require thorough and time-consuming work to make sure the selector and the array work together on different process nodes and across full parameter ranges. For now the priority has been on bringing ReRAM to market in embedded form.
Embed ReRAM now
“ReRAM is no longer the technology of the future – it is here now. We are now working with a number of potential customers to map the technology’s advantages to their specific design requirements,” said Coby Hanoch, CEO of Weebit Nano, in a statement.
Steve Kosier, CTO of SkyWater, said: “Weebit’s technology has excellent reliability even at high temperatures, and is tolerant to radiation and electro-magnetic fields, making it a great fit for many of our customers’ demanding target markets. The IP will be supported in our process design kit in the near future, allowing customers to confidently and easily integrate Weebit ReRAM into their designs.”
S130 includes a 256kbit ReRAM array, control logic, decoders, I/Os and error correcting code. The module is designed with additional patent-pending analog and digital circuitry running programming algorithms that significantly enhance the memory array’s technical parameters.
Full qualification of the Weebit ReRAM memory module in SkyWater’s US production fab is expected to be completed in the first half of 2023.
Weebit has partnered with the Nino Research Group (NRG) in the University of Florida’s Department of Materials Science and Engineering to study the effects of radiation on Weebit’s resistive random access memory (ReRAM) technology. Results of initial studies confirm Weebit ReRAM arrays are tolerant to high radiation levels.
Related links and articles:
Weebit tapes out ReRAM on 22nm FDSOI process
Infineon’s microcontrollers to go RRAM with TSMC
Weebit qualifies ReRAM for production on 130nm process
Weebit tapes out ReRAM demo chip with SkyWater foundry
Weebit moves ReRAM on to ‘secret-sauce’ materials