A 32-bit CPU with zero standby power and 1.5-clock sleep/2.5-clock wake-up achieved by utilizing a 180-nm C-axis aligned crystalline In-Ga-Zn oxide transistor

A flip-flop achieving high-speed backup utilizing a Si transistor and long-term retention with zero standby power by means of a transistor of c-axis aligned crystalline (CAAC) In-Ga-Zn oxide, a kind of CAAC oxide semiconductor, featuring extremely low off-state current is proposed. Using the flip-flop, a 32-bit processor has been fabricated with 350-nm Si/180-nm CAAC oxide semiconductor technology, and demonstrated data backup and power shutdown in 1.5 clock cycles at a low power of 1.77 nJ, data recovery in 2.5 clock cycles, and data retention with zero standby power for at least a day. According to simulation results, fast backup and long-term retention can also be achieved with 45-nm Si/180-nm CAAC oxide semiconductor technology.