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We have demonstrated the performance of inverted CH3NH3PbI3 perovskite-based solar cells (SCs) with a room temperature (RT) sputteredZnO electron transport layer by adding fullerene (C60) interlayer. ZnO exhibits a better matched conduction band level with perovskite and Al work function and around energy offset of 2.2eV between highest occupied molecular orbital level of CH3NH3PbI3perovskite and valance band level of ZnO. However, the CH3NH3PbI3perovskite layer will be damaged during direct RT sputteringdeposition of ZnO. Therefore, the C60 interlayer having matched conduction band level with ZnO and CH3NH3PbI3perovskite added between the CH3NH3PbI3perovskite and RT sputteredZnO layers for protection prevents sputtering damages on the CH3NH3PbI3perovskite layer. The short-circuit current density (JSC, 19.41 mA/cm²) and open circuit voltage (VOC, 0.91 V) of the SCs with glass/ITO/poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS)/perovskite/C60/RT sputtered ZnO/Al structure is higher than the JSC (16.23 mA/cm²) and VOC (0.90 V) of the reference SC with glass/ITO/PEDOT:PSS/perovskite/C60/bathocuproine (BCP)/Al structure. Although the SCs with the former structure has a lower fill factor (FF%) than the SCs with the latter structure, its conversion efficiency η% (10.93%) is higher than that (10.6%) of the latter. [ABSTRACT FROM AUTHOR]

The measuring accuracy of laser optical sensors is gradually degraded over time as a result of geometrical fluctuations of the laser beam. In a previous study by the present group, a method was proposed for stabilizing the laser beam by means of a rotating optical diffuser. In the present study, the effects of the key diffuser parameters, namely the rotational speed (ω), the particle radius (r), and the particle concentration (c), on the performance of the proposed system are evaluated both numerically and experimentally. The results confirm that given an appropriate setting of the three parameters, the proposed system reduces the variation of the image centroid position and improves the measuring accuracy of the laser optical sensor as a result. [ABSTRACT FROM AUTHOR]

In this study, the effects of annealing conditions on the magnetic characteristics of multilayered perpendicular magnetic tunnel junctions (pMTJ) of the structures SiNx/Pt/(Co/Pd)10/MgO/(Co/Pt)5/Pt with various MgO barrier thicknesses were explored. We found that both the fixed and free layers exhibit coercivity growth with increasing annealing temperature. Insertion of a 0.4 nm Mg layer under the MgO barrier layer increases the corecivities further. Magnetoresistance measured by the current-in-plane tunneling (CIPT) method reveals that the insertion of Mg layers on both side of the MgO layer can increase the MR ratio by up to 32%. [ABSTRACT FROM AUTHOR]

An interesting hydrogen sensor based on an Al0.24Ga0.76As Schottky barrier high-electron mobility transistor with a catalytic Pd metal/oxide/semiconductor is fabricated and demonstrated. In comparison with traditional Schottky diodes or capacitance-voltage type hydrogen sensors, the studied device exhibits larger current variation, lower hydrogen detection limit, and shorter transient hydrogen response time. Besides, good hydrogen-sensing properties, such as significant drain current change, threshold voltage shift, and transconductance change of transistor behaviors, are obtained. Therefore, the studied device provides the promise for high-performance solid-state hydrogen sensors, optoelectronic integrated circuits, and microelectromechanical system applications. [ABSTRACT FROM PUBLISHER]

Pd/InGaP hydrogen sensors based on the metal-oxide-semiconductor (MOS) and metal-semiconductor Schottky diodes have been fabricated and systematically studied. The effects of hydrogen adsorption on device performances such as the current-voltage characteristics, barrier height variation, hydrogen coverage, and heat of adsorption are investigated. The studied devices exhibit very wide hydrogen concentration detection regimes and remarkable hydrogen-sensing properties. Particularly, an extremely low hydrogen concentration of 15 ppm H2/air at room temperature can be detected. In addition, under the presence of oxide layers in the studied MOS device structure, the enhancements of barrier height and high-temperature operating capability are observed. The initial heat of adsorption for Pd/oxide and Pd/semiconductor interface are calculated as 355 and 65.9 meV/atom, respectively. Furthermore, the considerably short response times are found in studied devices. [ABSTRACT FROM PUBLISHER]

Focuses on the fabrication of a double channel pseudomorphic high-electron mobility transistor. Investigation on the detailed temperature-dependent performances; Use of field-effect transistors for microwave and power circuit applications; Insertion of undoped wide bandgap layer between the metal gate and active channels.

Investigates the performance of several III-V compound semiconductor devices. Significance of higher temperature tolerance in semiconductor devices; List of their weakpoints with regards to temperature increase.

Presents information on a study that examined a double ion-implant Ti-salicide technology for high-performance complementary metal oxide semiconductor devices. Background on Ti-salicide technology; Methodology of the study; Results and discussion.

Provides information on a study that developed a field-effect transistor using a high-barrier InGaP/GaAs/InGaAs camel-like gate. Discussion on the effect of the applied gate voltage on the barrier height for a homojunction camel-diode; Methodology; Results and discussion.

Focuses on a study which fabricated and examined two indium gallium phosphide/gallium arsenide resonant tunneling bipolar transistors with different superlattice structures in the emitters. Considerations in transistor characteristics; Analysis and comparison of multiple negative differential resistance characteristics; Conclusion.

The interesting hydrogen sensing performances of a Pt-oxide-AlGaAs (MOS) high electron mobility transistor (HEMT) are studied and demonstrated. The effects of hydrogen adsorption on device performances such as the threshold voltage shift ΔVth, drain saturation current variation ΔIDS, and transient response are presented. ΔVth and ΔIDS decreased with increasing operating temperature. This suggests that, at higher temperature, less hydrogen atoms diffuse through the Pt bulk and reach the interface between the Pt metal and oxide layer resulting from the relatively faster formation rate of hydroxyl on the Pt surface. The response curves of the studied Pt-AlGaAs MOS HEMT show various profiles at different temperatures. The influences of hydrogen concentration and temperature on the interface sites occupied by adsorbed atoms are also studied. [ABSTRACT FROM AUTHOR]

Describes the fabrication and analysis of a Pt/oxide/In[sub0.49]Ga[sub0.51]P metal-oxide-semiconductor Schottky diode hydrogen sensor. Steady-state and transient responses with different hydrogen concentrations and at different temperatures; Effects of the presence of dipoles at the oxide layer; Roles of hydrogen adsorption and desorption for the transient response at different temperatures.

Analyzes the capacitance-voltage characteristics of two-dimensional multi-conductor in liquid crystal displays (LCD). Implementation of an LC continuum theory by tensor; Description of the dependence of the capacitance on applied voltages; Result of the nonlinear capacitance in capacitive coupling.