High Retention-Time Nonvolatile Amorphous Silicon TFT Memory for Static Active Matrix OLED Display without Pixel Refresh

Abstract

Existing a-Si floating gate TFT (FG-TFT) nonvolatile memory suffers from two drawbacks: (i) short retention time and (ii) strong dependence of drain saturation current (ID,SAT) on drain voltage. In this study, we present (i) a new device structure that eliminates ID,SAT dependence on drain voltage; (ii) room-temperature retention time of >10 years; and (iii) the integration of this new TFT memory into AMOLED pixels, enabling displays without refresh and providing displays with the ability to store images without power.