Alleviation of abnormal NBTI phenomenon in LTPS TFTs on polyimide substrate for flexible AMOLED
Jaeseob Lee, Yongsu Lee, Taewook Kang, Hye‐Yong Chu, Jinoh Kwag
Abstract
Abstract This letter investigates the negative‐bias temperature instability (NBTI) behavior of p ‐channel low‐temperature polycrystalline silicon thin‐film transistors (LTPS TFTs) on plastic substrate. The measurements reveal that the threshold‐voltage positive shift is highly correlated to the passivation of grain boundary trap states. By applying the established phenomenon such as NBTI recovery and H diffusion from PI substrate, a new model is introduced to explain the mechanism and verified by the experiment. With the thick buffer and bottom metal layer or newly processed PI substrate, we succeeded in adjusting the NBTI behavior of LTPS TFTs on plastic substrate.
Topics & Concepts
Materials scienceSubstrate (aquarium)PassivationThin-film transistorOptoelectronicsLayer (electronics)AMOLEDTransistorThreshold voltageComposite materialVoltageElectrical engineeringActive matrixOceanographyGeologyEngineeringThin-Film Transistor TechnologiesSemiconductor materials and devicesAdvancements in Semiconductor Devices and Circuit Design