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We combine wavelet analysis and data fusion to investigate geomagnetically induced currents (GICs) on the Mäntsälä pipeline and the associated horizontal geomagnetic field, BH, variations during the late main phase of the 17 March 2013 geomagnetic storm. The wavelet analysis decomposes the GIC and BH signals at increasing "scales" to show distinct multi‐minute spectral features around the GIC spikes. Four GIC spikes >10 A occurred while the pipeline was in the dusk sector—the first sine‐wave‐like spike at ∼16 UT was "compound." It was followed by three "self‐similar" spikes 2 hr later. The contemporaneous multi‐resolution observations from ground‐(magnetometer, SuperMAG, SuperDARN), and space‐based (AMPERE, Two Wide‐Angle Imaging Neutral‐atom Spectrometers) platforms capture multi‐scale activity to reveal two magnetospheric modes causing the spikes. The GIC at ∼16 UT occurred in two parts with the negative spike associated with a transient sub‐auroral eastward electrojet that closed a developing partial ring current loop, whereas the positive spike developed with the arrival of the associated mesoscale flow‐channel in the auroral zone. The three spikes between 18 and 19 UT were due to bursty bulk flows (BBFs). We attribute all spikes to flow‐channel injections (substorms) of varying scales. We use previously published MHD simulations of the event to substantiate our conclusions, given the dearth of timely in‐situ satellite observations. Our results show that multi‐scale magnetosphere‐ionosphere activity that drives GICs can be understood using multi‐resolution analysis. This new framework of combining wavelet analysis with multi‐platform observations opens a research avenue for GIC investigations and other space weather impacts. Plain Language Summary: Geomagnetically Induced Currents (GIC) are produced by complex interaction between the Earth's magnetic field and geological composition during intense geomagnetic storms. These two parameters are often related in frequency domain. In this paper, we analyze the GIC signal from the Finnish natural gas pipeline recorded at Mäntsälä during the 17 March 2013 geomagnetic storm. Four spikes >10 A were recorded between 4:30 and 9:00 p.m. local time. We use wavelet analysis to learn about the frequencies of GIC spikes and then systematically investigate the observations from ground to space (ground‐up approach) to learn what links activity in space to the GICs. Wavelet analysis highlights areas ranging from <1 min to >30 min, which indicates that higher frequency fluctuations are accompanied with longer duration disturbance. Multi‐platform observations help us interpret the physical meaning of the multi‐minute (or multi‐scale) area in the wavelet plot. We find that multi‐scale activity in the magnetosphere and ionosphere, created by fast earthward‐flowing particles (magnetotail mesoscale plasma flows), ultimately drove the significant GIC spikes. This new perspective enabled us to link the magnetospheric activity to GICs through observations and previously published simulations and pave a path for future research. Key Points: Wavelet analysis of GICs at Mäntsälä on 17 March 2013 reveals two features—Pi1/Pi2 pulsations superposed on longer duration disturbancesWavelet decomposition of the GIC and BH signals is consistent with multi‐scale magnetosphere‐ionosphere activity around GIC spikesPi2 pulsations and data fusion suggest mesoscale flow channels (substorm injections) were the underlying cause of four GICs >10 A [ABSTRACT FROM AUTHOR]

The article studies the relationship amongst the structural properties of microcrystalline silicon and the performance of high-mobility microcrystalline-silicon thin-film transistors (TFTs). Findings suggest that the microcrystalline-silicon-TFT-based complementary-metal-oxide-semiconductor inverters with high voltage gains will be exceeding 22.

Several electrical in situ and ex situ measurements are conducted to study the influence of various environmental conditions, like dry oxygen and moisture on the electronic transport and device stability of the polycrystalline pentacene transistors. The analysis reveals that such conditions inhibits the injection of holes in the highest occupied molecular orbital level of the film, which further leads to an apparent reduction of the charge carrier mobility, as well as the threshold voltage.

Color detectors using multilayers of amorphous-silicon alloys expedite the detection of three fundamental components of visible light in one single pixel of a sensor array. To attain sensitivity for the blue, green and red components of light, three different bias voltages were used on the device. The experimentally observed transient photoresponse after switching on monochromatic light at various applied bias voltages revealed acceptable delay times.

An experiment was conducted to determine the efficiency of a nipiin two terminal device based on an amorphous silicon alloy which exhibits features such as good color separation and high dynamic range. The application of a nipiin structure for color detection was affected by a strong intensity dependence of the transient photocurrent response after bias voltage and light switching. A reverse biased diode of a photocurrent diode also showed a compensatory photocurrent activity as observed after the light was on and bias voltage switching was set at a range of +0.6V to 1V.

For the better performance of organic thin-film transistors (TFTs), gate-insulator surface treatments are often applied. However, the origin of mobility increase has not been well understood because mobility-limiting factors have not been compared quantitatively. In this work, we clarify the influence of gate-insulator surface treatments in pentacene thin-film transistors on the limiting factors of mobility, i.e., size of crystal-growth domain, crystallite size, HOMO-band-edge fluctuation, and carrier transport barrier at domain boundary. We quantitatively investigated these factors for pentacene TFTs with bare, hexamethyldisilazane-treated, and polyimide-coated SiO2 layers as gate dielectrics. By applying these surface treatments, size of crystal-growth domain increases but both crystallite size and HOMO-band-edge fluctuation remain unchanged. Analyzing the experimental results, we also show that the barrier height at the boundary between crystal-growth domains is not sensitive to the treatments. The results imply that the essential increase in mobility by these surface treatments is only due to the increase in size of crystal-growth domain or the decrease in the number of energy barriers at domain boundaries in the TFT channel. [ABSTRACT FROM AUTHOR]

The structural and transport properties of evaporated pentacene organic thin film transistors (TFTs) are reported, and they show the influence of the deposition conditions with different inorganic dielectrics. Dielectrics compatible with large area fabrication were explored to facilitate low cost electronics on glass or flexible plastic substrates. X-ray diffraction and atomic force microscopy show a clear correlation between the morphology and the structure of the highly polycrystalline films for all dielectrics investigated. The roughness of the dielectric has a distinct influence on the morphology and the structural properties, whereas the films on smooth thermal oxide are in general highly ordered and independent of the deposition conditions. The ordered films exhibit a "thin film" and a bulk phase, and the bulk phase volume fraction increases with the deposition temperature and the film thickness. Careful control of the deposition conditions gives virtually identical films on thermal oxide and silicon nitride dielectrics. The electronic properties of inverted staggered transistors show that the TFT mobility is correlated with the morphology and structure of the films. The TFTs exhibit very similar mobilities of ∼0.4 cm²/Vs and on/off ratios >10[sup 8] on thermal oxide and silicon nitride. The impact of the dielectric on the device parameters of mobility, threshold voltage, and subthreshold voltage slope is discussed. Temperature dependent measurements of the mobility were performed to study the influence of traps on electronic transport. Bias stress experiments were carried out to investigate the stability of the TFTs, and to gain understanding of the transport mechanisms of thermally evaporated pentacene TFTs. [ABSTRACT FROM AUTHOR]

The authors report on a survey of correlations between DSCS III satellite sunlit surface charging data and tabulated values of selected geomagnetic activity indices. This study is driven by the motivation to find a set of indices that have the potential to be used as proxies for determining the presence (nowcasting) and likely onset (forecasting) of surface charging. DSCS III data were compared with the Dst, ap, and the Polar Cap indices for a study period covering day 229, 1995 through day 115, 1999. Results show that: 1) significant correlations ([R.sup.2] [is greater than] 0.97) between average frame charging level and all three geomagnetic activity indices exist, and 2) the probability of charging events increases monotonically with increasing levels of geomagnetic activity until extreme levels are approached. It is postulated that during these extreme geomagnetic events, an anomalous source of neutralizing ions may be present at geosynchronous orbit either due to direct input from the solar wind or to ion outflow from the ionosphere.