A Long Wavelength-dependent Optical Memory Characteristics of Amorphous Oxide-based Thin Film Devices

摘要

We present an optical memory based on amorphous oxide thin films while analyzing its wavelength-dependent characteristics with a long wavelength (e.g. 500 nm, 600 nm), i.e. a lower photon energy compared to the band-gap. Here, the examined optical memory device has an amorphous In-Ga-Zn-O film incorporated as semiconducting absorption layer in the device. After an optical data writing for 300 sec, a stretched exponential function with a stretched exponent (β) and effective time constant (τ) is employed to analyze the retention trend for 600 sec. From analysis over the experimental results, the retention times after the long wavelength illumination are estimated through τ, and its orders of magnitude is found to be longer than 10⁴ sec at least. And this suggests the examined oxide-based device has good data retention characteristics even with a low photon energy light.