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Presents a study that investigated the deep levels and electrical properties in silicon and beryllium-coimplanted semi-insulating gallium arsenide. Experimental procedures; Results; Discussion.

Details a study which investigated the passivation and dissociation process of hydrogen-silicon donor complex in plasma-hydrogenated gallium arsenide. Temperature dependent values of dissociation frequencies; Results of the electric field annealing experiment; Dissociation kinetics of the hydrogen-donor complex.

Analyzes the deep levels in undoped bulk InP after rapid thermal annealing. Information on different insulating layers that form the MIS structures; Application of deep level transient spectroscopy in the study of the behavior of the rapid thermal annealed InP in metal-insulator-semiconductor (MIS) structures; Assessment of the effects of an insulating layer on interface states in the InP-MIS structure.

Presents a study that examined leakage current effects for the midgap levels in an aluminum/ gallium arsenide semiconductor junction using isothermal capacitance transient spectroscopy. Analysis of the temperature dependence of the leakage current density; Effect of leakage current on isothermal capacitance transient spectra; Examination of the emission rate in a capacitance transient.

Presents annealing and hydrogenation behaviors for EL2 and EL6 as dominant deep levels in gallium arsenide. Significance of deep levels in semiconductors; Direct relation between EL2 and EL6 in their origin; Behavior of the deep levels with annealing times.

Blue-emitting phosphors (Gd 1- x Ce x ) 5 Si 3 O 12 N (0 ≤ x ≤ 0.07) were prepared through a solid-state reaction under a reducing atmosphere. The excitation spectra exhibited several broad bands in the wavelength range from 240 to 400 nm, and the emission spectra consisted of a broad band covering from 360 to 550 nm. Two different emission centers corresponding to two different crystallographic sites in the host lattice were confirmed. The influence that the Ce 3+ concentration had on the photoluminescence of the prepared samples was examined, and the results indicate that an increase in the Ce 3+ concentration introduces a red-shift of the emission peak due to an increase in the Stokes shift. Concentration quenching occurs when the Ce 3+ content exceeds 3 mol%. In addition, the configurational coordinate model was used to finely explain the thermal quenching behavior of the phosphors. [ABSTRACT FROM AUTHOR]

Discusses a study which investigated hydrogenation effects on silicon- and beryllium-ion-implanted GaAs exposed to the hydrogen plasma. Change in electron mobilities that occurred in the sample hydrogenated for 60 minutes at room temperature; Factor responsible for defect and impurity passivation in crystalline semiconductor materials; Reasons for not utilizing atomic hydrogen processing.

Focuses on a study which investigated the deep electron traps in gallium arsenide layers grown on (100) silicon substrates by metalorganic chemical vapor deposition. Difference between gallium arsenide on silicon substrates and gallium arsenide substrates; Description of the experiment; Result and discussion.

Single crystalline Si epilayers were grown on sapphire (1 1¯ 0 2) substrates through a three-step growth method by rapid thermal chemical vapor deposition (RTCVD). Hydrogenation of the epilayers was performed by the hydrogen-plasma exposure (HPE) in a remote plasma chemical vapor deposition (RPCVD) system, following rapid thermal annealing. It was found that the hydrogenation treatment improves the crystallinity of the Si epilayer as well as the electrical properties of Si epilayers. After hydrogenation, especially, the intensity of the deep level defects which are responsible for the lattice mismatch between Si and the sapphire substrate decreases. Also, dislocations and microtwins are reduced remarkably, improving the crystallinity. In Schottky diodes fabricated on hydrogenation-processed Si epilayers, the leakage current decreases one order of magnitude in comparison to non-hydrogenated samples. It is suggested that these characteristics could be explained by the hydrogen incorporation at defects. [Copyright &y& Elsevier]

Deep levels in GaAs on Si substrates grown by metalorganic chemical vapor deposition (MOCVD) were studied during infrared rapid thermal annealing. For GaAs layers on Si after annealing at 850 °C for 20 s, three electron deep levels at 0.36, 0.27, and 0.20 eV below the conduction band were created as the dominant deep levels. Especially, the 0.36 eV level was found to increase up to 40% of the donor concentration as the thickness of Si substrates increased. These results indicate that rapid thermal annealing of GaAs on Si may induce high-density deep levels due to a biaxial tensile stress caused by the difference in thermal expansion coefficients. [ABSTRACT FROM AUTHOR]

The effect of hydrogen plasma exposure on the deep levels in GaAs grown by the horizontal Bridgman method was studied. After hydrogenation at 250 °C for 3 h, the concentrations of the electron deep levels, such as the EL2 trap (Ec-0.81 eV), the EL3 trap (Ec-0.63 eV), and the EL6 trap (Ec-0.35 eV), decrease by one order of magnitude. On the other hand, three new electron traps at Ec -0.42 eV, Ec -0.54 eV, and Ec -0.94 eV are created. After rapid thermal annealing up to 550 °C for 10 s, these created traps are reduced and the deep levels decreased by hydrogenation recover nearly completely. This result reveals that the passivation and creation of deep levels by hydrogenation may be explained as the interaction of atomic hydrogen with an unsaturated bond of native defects. [ABSTRACT FROM AUTHOR]

Discusses the metastable states of the EL2 family discovered from the measurement of photocapacitance quenching. Purpose of deep level transient spectroscopy; Illustration of the arsenic antisite model involved with the interstitial arsenic and the double vacancy.

We have fabricated Si nanocrystals utilizing nanometer-sized Pt islands acting as etching-masks on SiOx/amorphous-Si/SiOx/p-Si (1 0 0) thin films. In the measurement of transmission electron microscopy the Si nanocrystals embedded in SiO2 were observed, and in the measurement of cathodoluminescence spectroscopy at 77 K Si nanocrystal-related peaks were observed at 462 and 647 nm. For the Al/SiO2/nanocrystalline-Si/SiO2/p-Si capacitor structure, a hysteretic behavior with the flatband voltage shift of 0.592 V was observed in the measurement of capacitance–voltage characteristic at 300 K. These results indicate that Si nanocrystals can be formed by using a nanosized Pt island etching-mask, and that Si nanocrystals embedded in SiO2 layer act as Si quantum dots which hold promise potential applications. [Copyright &y& Elsevier]

The band alignment and defect states of GaInZnO thin films grown on SiO2/Si via radio frequency (RF) magnetron sputtering were investigated by using X-ray photoelectron spectroscopy, reflection electron energy loss spectroscopy, thermally stimulated exo-electron emission and photo-induced current transient spectroscopy.The band gap via reflection electron energy loss spectroscopy was 3.2 eV. The defect states via photo-induced current transient spectroscopy and thermally stimulated exo-electron emission were at 0.24, 0.53, 1.69 and 2.01 eV below the conduction band minimum of GIZO thin films, respectively. The defect states at 0.24 and 0.53 eV are related to the field-effect mobility, and the defect stated at 1.69 and 2.01 eV is related to the oxygen vacancy defect. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We investigated the relationship between band alignments and threshold voltage shifts of GaInZnO (GIZO) thin films grown on SiO 2 /p ++ -Si by the RF sputtering method via utilizing X-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The band gap energies of the GIZO thin films are increased from 3.03 eV to 3.43 eV with the increase in their Gallium (Ga)/Indium (In) ratios of 0.83, 1.05, and 1.34. The barrier height of GIZO/Mo is also increased by increasing in the Ga/In ratio, and then the threshold voltages positively shift. From the result of DLTS, it is found that the D defect is located at 0.56 eV below the conduction band, and its defect density shows the increasing tendency by the increase in the ratio of Ga/In (i.e. the decrease in In content). From the transfer curves of the GIZO thin films, the mobility shows the decreasing tendency by the increase in the ratio of Ga/In. As a result, it is suggested that the increase in the density of D defect density in the GIZO thin film plays a dominant role in the decrease in its mobility. [ABSTRACT FROM AUTHOR]

Defect states of hydrogenated amorphous silicon nitride (a-SiNx:H) thin films were measured using the thermally stimulated exoelectron emission spectroscopic method. The defect states of films with nitrogen to silicon composition ratios (x) of 0.92, 1.21, and 1.44 were found to be located 1.66, 1.77, and 1.82 eV below the conduction band minimum, respectively. We confirmed that the hydrogen concentration decreased as x was increased via an elastic recoil detection analysis experiment, while as the hydrogen concentration increased, the defect concentration decreased. From these results, we concluded that the defect centers could be related to dangling bonds, the so-called K centers, in silicon nitride. Furthermore, as the concentration of Si H was increased with decreasing x via the infrared spectroscopy, the defect density was reduced through the defect passivation. [ABSTRACT FROM AUTHOR]

Abstract: The effects of varying the conditions for the chemical bath deposition (CBD) of cadmium sulfide (CdS) layers on CdS/Cu(In,Ga)Se2 (CIGS) hetero-junctions were investigated using photoluminescence (PL), electroluminescence (EL), deep level transient spectroscopy (DLTS), and red-light-illuminated current-voltage (I–V) measurements. We demonstrated that varying CBD-CdS conditions such as the temperature and time influenced the recombination pathways around the CdS/CIGS junction via the formation of different electronic defects, which eventually changed the photovoltaic conversion efficiency. As the CBD-CdS time and temperature were increased, the cell efficiency decreased. PL measurements revealed that this degradation of the cell efficiency was accompanied by increases in the defect-related recombination, which were attributed to the existence of donor defects around CdS/CIGS having an energy level of 0.65eV below conduction band, as revealed by DLTS. Increasing distortions in the red-light-illuminated I–V characteristics suggested that the related defects might also have played a critical role in metastable changes around the CdS/CIGS junction. Because the CBD-CdS time and temperature were considered to influence the diffusion of impurities into the CIGS surface, the evolution of the efficiency, PL spectra, defect populations, and red-light-illuminated I–V characteristics observed in this work could be attributed to the diffusion of impurities during the CBD-CdS process. [Copyright &y& Elsevier]

We report on rapid thermal chemical vapor depositiongrowth of silicon nanowires (Si NWs) that contain a high density ofgold nanoclusters (Au NCs) with a uniform coverage over the entirelength of the nanowire sidewalls. The Au NC-coated Si NWs with anantibody-coated surface obtain the unique capability to capture breastcancer cells at twice the highest efficiency currently achievable(∼88% at 40 min cell incubation time) from a nanostructuredsubstrate. We also found that irradiation of breast cancer cells capturedon Au NC-coated Si NWs with a near-infrared light resulted in a highmortality rate of these cancer cells, raising a fine prospect forsimultaneous capture and plasmonic photothermal therapy for circulatingtumor cells. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

The minority carrier (electron) capture process and the interface trap density of a TiN/Al[sub 2]O[sub 3]/p-Si metal-oxide-semiconductor capacitor were examined by deep level transient spectroscopy (DLTS). It was found that the activation energies of the large peaks detected at higher temperatures with gate bias voltages of 1.8, 1.5, 1.3, and 1.1 V were 0.19, 0.24, 0.29, and 0.37 eV, respectively. These energies were related to the electron-capture process from the conduction band by interface states in the upper half of the Si band gap. The interface state passivation effect of postannealing in a hydrogen ambient was studied from the minority carrier capture process and the usual DLTS signals. The D[sub it] at an energy of 0.35 eV from the valence bandedge decreased from 1 × 10[sup 12] cm[sup -2] eV[sup -1] at the as-fabricated state to 4 × 10[sup 11] cm[sup -2] eV[sup - 1] after H[sub 2] annealing at 450 °C. It was also found that the D[sub it] at an energy of 0.3 eV from the conduction bandedge decreased to the same amount by the same annealing process. [ABSTRACT FROM AUTHOR]

This section presents a correction to the article "Full Surface Embedding of Gold Clusters on Silicon Nanowires for Efficient Capture and Photothermal Therapy of Circulating Tumor Cells," that was published in a previous issue.