Search

The negative gate bias stress (NBS) reliability of n-type polycrystalline silicon (poly-Si) thin-film transistors (TFTs) with a distinct defective grain boundary (GB) in the channel is investigated. Results show that conventional NBS degradation with negative shift of the transfer curves is absent. The on-state current is decreased, but the subthreshold characteristics are not affected. The gate bias dependence of the drain leakage current at V ds of 5.0 V is suppressed, whereas the drain leakage current at V ds of 0.1 V exhibits obvious gate bias dependence. As confirmed via TCAD simulation, the corresponding mechanisms are proposed to be trap state generation in the GB region, positive-charge local formation in the gate oxide near the source and drain, and trap state introduction in the gate oxide. [ABSTRACT FROM AUTHOR]

We have developed a process to grow high-crystallinity silicon films on insulators by intermittent pulse heating (IPH)-assisted plasma-enhanced chemical vapor deposition to address a drawback of incubation layer formation at the early stage of growth. By applying electrical pulses (22 V, 5 Hz, 10% duty ratio) to a Mo strip underneath a SiO2 layer, the surface is instantaneously heated to 1050 K while maintaining a steady substrate temperature of 670 K. The growth mechanism similar to that of solid-phase epitaxy enhanced its growth rate up to 1.2 nm s−1, which is five times greater than that of a-Si grown outside the Mo strip. The grown films assisted with IPH also showed a 97% crystalline volume fraction with no incubation layer. [ABSTRACT FROM AUTHOR]

This study demonstrated a polycrystalline-silicon (poly-Si)-based double-gate (DG) ion-sensitive field-effect transistors (DG-ISFETs) using APTES/SiO2 stack-sensing membrane. The APTES/SiO2 stack-sensing membrane enhanced the single-gate (SG) sensitivity, and suppressed the hysteresis. The DG structure was preferred to have a capacitive coupling effect and to amplify the sensitivity of ISFETs. The sensitivities of SG- and DG-ISFETs were approximately 56.8 and 294 mV pH−1, respectively. In addition, the corresponding amplifying factor was approximately 5.2. With this approach, the poly-Si DG-ISFETs can be a candidate for future high-performance biochemical sensing applications. [ABSTRACT FROM AUTHOR]