Renesas and TSMC have collaborated on MCUs with on-chip flash memory since the 90 nm technology generation. Four years after working together on 40 nm MCU platform and production, the two companies are now extending their collaboration to develop 28 nm MCUs. Through this collaboration, Renesas’ highly reliable and fast Metal-Oxide-Nitride-Oxide-Silicon (MONOS) eFlash technology will combine with TSMC’s high-performance, low-power 28 nm high-K metal gate process technology to produce automotive MCUs for a broader range of applications such as autonomous vehicle sensor control, coordinated control among electronic control units (ECUs), fuel-efficient engine control for green vehicles, and highly efficient motor inverter control for electric vehicles.
ECUs capable of safely controlling autonomous-driving functionality require, Renesas says, next-generation control MCUs that contribute to fast processing of complex control tasks (including fail-operational capabilities, security, and support for coordinated control among multiple ECUs), power efficiency of the overall system, and functional safety. To meet ever stricter emission regulations, fuel-efficient engines for next-generation green vehicles require powerful computing performance to implement new combustion systems as well as robust and large-capacity on-chip flash memory to accommodate larger firmware programs. A growing need for environmental friendliness and longer cruising range in electric vehicles (EVs) and plug-in hybrid vehicles (PHVs) creates demand for MCUs with improved computing performance and greater function integration to enable more efficient and compact motor inverters.
There is also a need for large-capacity flash memory to allow more fine-grained support for the environmental regulations and standards of various countries as well as to enable over-the-air (OTA) wireless updating of control programs. Technology for embedding flash memory with superior performance and excellent safety in MCUs is also needed to implement next-generation control technology for a safe and secure society, for example in industrial fields such as Industry 4.0 and social infrastructure fields.
The partners assert that with the 28 nm eFlash process technology developed through this collaboration, MCUs can meet the demands of next-generation automotive computing by delivering a maximum of more than four times the program memory capacity and greater than four-fold performance improvement compared to the current 40 nm technology. Other enhancements on the new MCUs include the use of multiple CPU cores, more advanced security, and support for multiple interface standards.
Renesas’ Metal-Oxide-Nitride-Oxide-Silicon (MONOS) embedded flash technology
MONOS is a structure in which each transistor in the flash cell consists of three layers—oxide, nitride, and oxide—on a silicon base, with a metal control gate at the top. Renesas has accumulated more than two decades of experience in the use of MONOS flash memory technology by providing MCUs for IC cards. Based on the track record in MONOS technology, Renesas extended the technology by developing a split-gate (SG) structure suitable for MCU internal flash memory. The new “SG-MONOS” –type flash memory realizes MCUs with high reliability, high speed and low power consumption.