A 48 MHz 880-nW Standby Power Normally-Off MCU with 1 Clock Full Backup and 4.69-μs Wakeup Featuring 60-nm Crystalline In–Ga–Zn Oxide BEOL-FETs

We have prototyped a microcontroller (MCU) that employs crystalline In–Ga–Zn oxide transistors having an extremely low off current below 10−21 A. The IGZO-based MCU can retain data during power gating in both of its processing unit and memory, and there is an integrated voltage regulator that can store the reference voltage. The MCU is prototyped with the combination of 60-nm IGZO (in BEOL) and 110-nm Si CMOS processes. It has a standby power of 880 nW, a system backup time of 21 ns and a system wakeup time of 4.69 μs. The MCU that employs IGZO technology can be applied to devices which require low power consumption as well as fast wakeup.