No abstract

This study examines the effect of the annealing time of the Y 2 O 3 passivation layer on the electrical performances and bias stabilities of sol−geldeposited SnO 2 thin-film transistors (TFTs). The environmental stabilities of SnO 2 TFTs were examined. After optimizing the Y 2 O 3 passivation layers in SnO 2 TFTs, the field-effect mobility was 7.59 cm 2 /V•s, the V TH was 9.16 V, the subthreshold swing (SS) was 0.88 V/decade, and the on/off-current ratio was approximately 1 × 10 8 . V TH shifts were only −0.18 and +0.06 V under negative and positive bias stresses, respectively. The SnO 2 channel layer thickness and oxygenvacancy concentration in SnO 2 , which determine the carrier concentration, were successfully tuned by controlling the annealing time of the Y 2 O 3 passivation layers. An extremely thin Y 2 O 3 passivation layer effectively blocked external molecules, thus affecting the device performance. The electrical performance was maximized in SnO 2 TFTs using a 15 min-annealed Y 2 O 3 passivation layer. In this TFT, the field-effect mobility was maximally retained and the bias and environmental stabilities were sustained over 90 days of air exposure.

In this study, sol–gel-processed amorphous-phase ZrO2 was used as an active channel material to improve the resistive switching properties of resistive random access memories (RRAMs). ITO/ZrO2/Ag RRAM devices exhibit the properties of bipolar RRAMs. The effect of the post-annealing temperature on the electrical properties of the ZrO2 RRAM was investigated. Unlike the ZrO2 films annealed at 400 and 500 °C, those annealed at 300 °C were in amorphous phase. The RRAM based on the amorphous-phase ZrO2 exhibited an improved high-resistance state (HRS) to low-resistance state ratio (over 106) as well as promising retention and endurance characteristics without deterioration. Furthermore, its disordered nature, which causes efficient carrier scattering, resulted in low carrier mobility and the lowest leakage current, influencing the HRS values.