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In this study, we have compared the performance of self-aligned a-IGZO thin-film transistors (TFTs) whereby the source/drain (S/D) region's conductivity enhanced in three different ways, that is, using SiNx interlayer plasma (hydrogen diffusion), using calcium (Ca as reducing metal) and using argon plasma (changing the atomic ratio). All these TFTs show comparable characteristics such as field-effect mobility (μFE) of over 10.0 cm2/(V.s), sub-threshold slope (SS-1) of 0.5 V/decade, and current ratio (ION/IOFF) over 108. However, under negative-bias-illumination-stress (NBIS), all these TFTs showed strong degradation. We attributed this NBIS stability issue to the exposed S/D regions and changes in the conductivity of S/D contact regions. The hydrogen plasma-treated TFTs showed the worst NBIS characteristics. This is linked to increased hydrogen diffusion from the S/D contact regions to the channel. In this study, we observed that the negative-bias-illumination-stress stabilities of self-aligned a-IGZO thin-film transistors are strongly dependent upon the source/drain (S/D) region's direct exposure to stress light. Among few different techniques for S/D conductivity enhancements such as metal reduction (Ca metal), Ar plamsa, and SiNx plasma (hydrogen diffusion), the SiNx plasma-treated thin-film transistors showed the worst negative-bias-illumination-stress suitabilities. This is linked to increased hydrogen diffusion from the S/D contact regions to the channel. cop. 2015 Society for Information Display.

We present a QVGA (320x240 with 3 sub-pixel) top-emitting AMOLED display with 250ppi resolution using a self-aligned (SA) IGZO TFT backplane on polyimide-foil with full barrier. The back plane process flow is based on a 7 layer photolithography process. The aperture ratio of the top-emitting OLEDs is approx. 80%. An integrated gate driver is shown that can be driven at operation speed equivalent to a 4k2k display at 100Hz

We describe the device and transport characteristics of amorphous zinc tin oxide thin-film (ZTO) transistors. In samples with a sufficiently high mobility and at a high gate voltage, a crossover occurs from transport governed by thermal excitation of trapped charges to one where the charge carriers reside for a sufficiently long time in extended states. Very few semiconductors exhibit this range of behavior in the same device under different conditions. We also describe the correct methods to extract mobility values and ionization energies from current voltage characteristics.

A process to make self-aligned top-gate amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) on polyimide foil is presented. The source/drain (S/D) region's parasitic resistance reduced during the SiN interlayer deposition step. The sheet resistivity of S/D region after exposure to SiN interlayer deposition decreased to 1.5 kΩ/□. TFTs show field-effect mobility of 12.0 cm2/(V.s), sub-threshold slope of 0.5 V/decade, and current ratio (I ON/OFF) of >107. The threshold voltage shifts of the TFTs were 0.5 V in positive (+1.0 MV/cm) bias direction and 1.5 V in negative (-1.0 MV/cm) bias direction after extended stressing time of 104 s. We achieve a stage-delay of ~19.6 ns at V-DD = 20 V measured in a 41-stage ring oscillator. A top-emitting quarter-quarter-video-graphics-array active-matrix organic light-emitting diode display with 85 ppi (pixels per inch) resolution has been realized using only five lithographic mask steps. For operation at 6 V supply voltage (V-DD), the brightness of the display exceeds 150 cd/m2. A process to make self-aligned top-gate amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) is presented. TFTs show field-effect mobility of 12.0 cm2/(V.s), sub-threshold slope of 0.5 V/decade, and current ratio (I ON/OFF) of over 107. In applications, a 41-stage ring oscillator with a stage-delay of ~19.6 ns (at V-DD = 20 V) and a top-emitting quarter-quarter-video-graphics-array (QQVGA) active-matrix organic light-emitting diode (AMOLED) display with 85 ppi (pixels per inch) resolution using five lithographic mask steps have been realized on a polyimide foil. Copyright 2015 Society for Information Display.

We present a QQVGA (160times120 with 3 sub-pixel) top-emitting AMOLED display with 85ppi resolution using a self-aligned (SA) IGZO TFT backplane on polyimide-foil. The back plane process flow is based on a 5 layer photolithography process. The aperture ratio of the top-emitting OLEDs is approx. 25%. For operation at 6 V supply voltage (VDD), the brightness of the display exceeds 150cd/m2. On the same substrate a 160 stage gate-driver was measured at FHD rate. cop. 2014 Society for Information Display.

AMOLED backplanes were fabricated on both rigid glass and flexible plastic substrates using a solution processed oxide semiconductor processed at temperatures

The relationship between mnemonic instruction and academic performance for secondary-school-age youth with disabilities was explored in this systematic review. A total of 20 studies intervening with 669 youth with learning disabilities, emotional and behavioral disorders, and mild developmental disabilities were reviewed. The findings of this review strongly support the efficacy of mnemonic interventions across study methods, educational settings, student ages, and disabilities in the improvement of academic performance, typically measured by recall of word meanings or factual information. A series of detailed implications for practice is discussed and reference is made to specific literature providing detailed descriptions of mnemonic interventions.

In this work, we present the impact of S/D contact formation, that is, by SiN plasma doping (hydrogen incorporation), metallic reduction (by calcium) and by argon plasma (compositional change) on NBIS instabilities of self-aligned a-IGZO TFTs.