Crystalline IGZO ceramics (crystalline oxide semiconductor)–based devices for artificial intelligence

Abstract

AbstractIn 2009, a crystalline oxide semiconductor with a layered structure, which we refer to as c‐axis–aligned crystalline indium‐gallium‐zinc oxide (CAAC‐IGZO), was first discovered. CAAC‐IGZO has a peculiar crystal structure in which clear grain boundaries are not observed despite high c‐axis alignment and absence of a‐b plane alignment. When compared to a Si field‐effect transistor (FET), a metal‐oxide‐semiconductor (MOS) FET, utilizing CAAC‐IGZO, presents lower off‐state current (on the order of yA [10−24 A]). These unique characteristics allow CAAC‐IGZO to realize devices with low power consumption. With the emerging era of artificial intelligence, wherein power saving becomes more significant, CAAC‐IGZO has attracted attention as a potential replacement for Si. This paper describes the characteristics and potentials of CAAC‐IGZO for the development of memory devices with unprecedented functions.