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In this study, we present an optically tunable feedback field-effect transistor (FBFET) with two independent gates and a p+-i-n+ silicon nanowire. Because of the feedback operation, the FBFET features extremely steep switching characteristics with subthreshold swings <4 mV dec−1, and it can be reconfigured as a p- or n-type transistor by controlling the gate-voltage biases. When the FBFET is exposed to a He–Ne laser beam (λ = 633 nm), photogenerated carriers accumulate in the potential wells and reduce the potential-barrier height. The optically tunable feedback operation is attributed to the lowering of the potential barrier caused by the light. The triggering voltages can be modulated according to illumination, even when feedback is being provided. This optically tunable transistor with excellent switching characteristics opens up possibilities for application in future optoelectronic devices. [ABSTRACT FROM AUTHOR]

Examines the photoluminescence (PL) spectrum of undoped epitaxial wurtzite GaN (gallium nitride) layers on sapphire for applied hydrostatic pressures. Characteristics of GaN; Relevance of pressure dependence of the PL of GaN; Magnitudes of the linear and quadratic pressure coefficients for wurtzite GaN.

In this study we investigate the influence of substrate materials on the electrical characteristics of feedback field-effect transistors (FETs) when subjected to bending fatigue. Each of our transistors are composed of a p+–i–n+ doped silicon nanowire and dual-top metal gates. Feedback FETs on Ecoflex substrates feature outstanding stability compared to those on polyethersulphone and polydimethysiloxane substrates, even at a bending strain of 11.67%. The threshold voltage shift is within the range of 0.3 V, and the on-current only decreases by 15.5% (or less), when compared to the initial flat conditions. Moreover, our devices have outstanding reliability, even after 5000 cycles of repeated bending. [ABSTRACT FROM AUTHOR]

In this study, we investigate the influence of an overlap between the gate and source/drain regions of a-Si:H thin film transistors (TFTs) on their electrical characteristics under tensile or compressive strain through experiment and mechanical simulation. The strain distribution in the a-Si:H TFT for a bending radius of 2mm reveals that the strain at both ends of the TFT is ten times larger than that at the source-drain current path. The overlap lowers the stress sustained by the TFT in the region comprised between the channel and the gate insulator; therefore, TFTs with the overlap operate even at a tensile strain of 2.54%. In particular, the overlap is remarkably effective on relaxing the stress sustained in the interface between the gate insulator and the gate electrode, consequently improving the electrical stability of the bent TFT. [ABSTRACT FROM AUTHOR]

We investigate the electroluminescence (EL) characteristics of a hybrid light-emitting diode (HyLED) with an emissive layer comprised of CdSe/Cd/ZnS core-shell nanoparticles (NPs) embedded in poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) on a plastic substrate. The EL characteristics change dramatically with increasing of the biased voltage. At low voltages, recombination of electrons and holes occurs only in the PFO film because of poor charge transfer in the PFO-CdSe/Cd/ZnS NPs composite film, while the color of the light-emitting from the HyLED changes from blue to red as the biased voltage increases from 7.5 to 17.5V. We examine and discuss the mechanism of this color tunability. [ABSTRACT FROM AUTHOR]

We report luminescent characteristics and mechanical stability of a flexible organic light-emitting diode (FOLED) using an amorphous ZnO-doped In2O3 (a-IZO) anode with a low sheet resistance of 18.9 Ω/◻ and a high optical transparency of 86%. The FOLED consisting of a-IZO/poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS)/poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4, 8-diyl)] (F8BT)/LiF/Al exhibits the efficient luminescent characteristics, which are nearly identical with the photoluminescence spectrum of the organic emitting material in our FOLED. This observation clearly indicates that the luminescent characteristics of the FOLED are solely ascribed to molecular exciton formation within the F8BT layer, since exciplex and charge transfer exciton formation are strictly suppressed by both tunneling/thermionic injection of holes at the PEDOT:PSS/F8BT interface and enhanced hole transport. Furthermore, the use of the considerably flexible a-IZO anode and PEDOT:PSS acting as a strain-relief buffering material enables good retention of the efficient luminescent characteristics of the FOLED even after continuous bending of up to 1000 times. [ABSTRACT FROM AUTHOR]

In this study, a laterally coupled device composed of a photodiode and a Si nanowires-field-effect transistor (NWs-FET) is constructed on a plastic substrate and the coupled device is characterized. The photodiode is made of p-type Si NWs and an n-type ZnO film. The Si NWs-FET is connected electrically to the photodiode in order to enhance the latter's photocurrent efficiency by adjusting the gate voltage of the FET. When the FET is switched on by biasing a gate voltage of -9 V, the photocurrent efficiency of the photodiode is three times higher than that when the FET is switched off by biasing a gate voltage of 0 V. [ABSTRACT FROM AUTHOR]

Omega-shaped-gate (OSG) nanowire-based field effect transistors (FETs) have attracted a great deal of attention recently, because theoretical simulations predicted that they should have a higher device performance than nanowire-based FETs with other gate geometries. OSG FETs with channels composed of ZnO nanowires were successfully fabricated in this study using photolithographic processes. In the OSG FETs fabricated on oxidized Si substrates, the channels composed of ZnO nanowires with diameters of about 110 nm are coated with Al2O3 using atomic layer deposition, which surrounds the channels and acts as a gate dielectric. About 80% of the surfaces of the nanowires coated with Al2O3 are covered with the gate metal to form OSG FETs. A representative OSG FET fabricated in this study exhibits a mobility of 30.2 cm2/ (V s), a peak transconductance of 0.4 μS (Vg = −2.2 V), and an Ion/Ioff ratio of 107. To the best of our knowledge, the value of the Ion/Ioff ratio obtained from this OSG FET is higher than that of any of the previously reported nanowire-based FETs. Its mobility, peak transconductance, and Ion/Ioff ratio are remarkably enhanced by 3.5, 32, and 106 times, respectively, compared with a back-gate FET with the same ZnO nanowire channel as utilized in the OSG FET. [ABSTRACT FROM AUTHOR]

Tunnel field-effect transistors (TFETs) with a subthreshold swing (SS)<60 mV/dec are expected to be active devices in low-power flexible systems, potentially lowering operational voltage by virtue of steep switching behavior via band-to-band tunneling. In silicon (Si) channel materials, however, it still remains a challenge to obtain SS smaller than 60 mV/dec. In this study, we experimentally demonstrate the sub-60 mV/dec operation of a flexible semi-around gate TFET on a plastic substrate using Si nanowires (SiNWs) as the channel material. With the combined advantages of selectively thinned SiNW channels (width ~15 nm and height ~40 nm) and high-κ (Al2O3 ~7 nm) gate dielectric, in conjunction with an abrupt degenerate source junction, the device with a channel length of ~500 nm exhibits a minimal SS of ~42 mV/dec at room temperature. Moreover, mechanical bendability of the device indicates that it has stable and good fatigue properties, providing an important step towards the realization of steep-slope switches for low-power and energy-efficient flexible electronics. [ABSTRACT FROM AUTHOR]

We demonstrate a pn heterojunction diode constructed with a n-type ZnO nanowire (NW) and a p-type HgTe nanoparticle (NP) thin film on a SiO2/p-Si substrate. For the pn heterojunction diode, the rectifying characteristics of both the dark current and the photocurrent excited by 633 nm wavelength light were observed, but the photocurrent excited by 325 nm wavelength light possesses Ohmic characteristics. The optoelectronic characteristics of the pn heterojunction diode were compared with those of the ZnO NW and HgTe NP thin film composing it. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate nondestructive readout memory characteristics of a bistable resistor (biristor) with an n+-p-n+ Si nanowire (SiNW) channel on a bendable substrate. The SiNW channel is fabricated using a top--down route, which is compatible with the current complementary metal-oxide-semiconductor technology. The SiNW biristor shows the outstanding memory characteristics such as a retention time of 10 s and a current sensing margin of ~23-μA at room temperature. These memory characteristics originate from a positive feedback process resulting from impact ionization near the p-n junction. Moreover, the positive feedback mechanism is comprehensively investigated using device simulation. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate the bipolar resistive switching characteristics of flexible resistive random access memory (ReRAM) devices, whose bottom electrodes are made of silicon nanowires (Si NWs) with a triangular structure, which offer preferential sites for the filaments. The temperature dependence of the low resistance state (LRS) of the resistive Al2O3/ZnO bilayers of ReRAM devices reveals that Ag filaments originating from the top Ag electrodes are responsible for bipolar resistive switching. With respect to the endurance characteristics of the LRS, resistance fluctuation is negligible because of the filaments generated at the specific sites of the vertices of the Si NW bottom electrodes. In addition, the resistive switching characteristics are maintained even after 1000 bending cycles. [ABSTRACT FROM AUTHOR]

In this study, we investigate the electrical characteristics of bendable a-Si:H thin-film transistors (TFTs) with various channel widths as a function of bending stress. Compared with a narrower channel TFT, a wider channel TFT exhibits a stable performance even at a bending strain of 1.3%. Our stress and strain distribution analysis reveals an inverse relationship between the channel width and the channel stress. As the channel width widens from 8 to 50 μm, the stress experienced by the middle channel region decreases from 545 to 277 MPa. Moreover, a 50 μm-channel-width TFT operates stably even after a 15 000 bending cycle while the 8 μm-channel-width TFT fails to operate after a 2000 bending cycle. [ABSTRACT FROM AUTHOR]

In this study, we report the electrical and mechanical characteristics of fully transparent indium zinc oxide (IZO) thin-film transistors (TFTs) fabricated on stress-relieving bendable substrates. An IZO TFT on a stress-relieving substrate can operate normally at a bending radius of 6mm, while an IZO TFT on a normal plastic substrate fails to operate normally at a bending radius of 15mm. A plastic island with high Young's modulus embedded on a soft elastomer layer with low Young's modulus plays the role of a stress-relieving substrate for the operation of the bent IZO TFT. The stress and strain distributions over the IZO TFT will be analyzed in detail in this paper. [ABSTRACT FROM AUTHOR]

Inthis study, we present the steep switching characteristics of bendablefeedback field-effect transistors (FBFETs) consisting of p–i–n nanowires (NWs) and dual-top-gatestructures. As a result of a positive feedback loop in the intrinsicchannel region, our FBFET features the outstanding switching characteristicsof an on/off current ratio of approximately 106, and pointsubthreshold swings (SSs) of 18–19 mV/dec in the n-channeloperation mode and of 10–23 mV/dec in the p-channel operationmode. Not only can these devices operate in n- or p-channel modes,their switching characteristics can also be modulated by adjustingthe gate biases. Moreover, the device maintains its steep SS characteristics,even when the substrate is bent. This study demonstrates the promisingpotential of bendable NW FBFETs for use as low-power components inintegrated circuits or memory devices. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate the bipolar resistive switching characteristics of flexible resistive random access memory (ReRAM) devices, whose bottom electrodes are made of silicon nanowires (Si NWs) with a triangular structure, which offer preferential sites for the filaments. The temperature dependence of the low resistance state (LRS) of the resistive Al2O3/ZnO bilayers of ReRAM devices reveals that Ag filaments originating from the top Ag electrodes are responsible for bipolar resistive switching. With respect to the endurance characteristics of the LRS, resistance fluctuation is negligible because of the filaments generated at the specific sites of the vertices of the Si NW bottom electrodes. In addition, the resistive switching characteristics are maintained even after 1000 bending cycles. [ABSTRACT FROM AUTHOR]

We construct a flexible pn heterostructured photodiode using a CdTe nanoparticle thin film and a single ZnO nanowire (NW) on a plastic substrate. The photocurrent characteristics of the flexible photodiode are examined under illumination with 325 nm wavelength light and the photocurrent efficiencies at bias voltages of +- 2.5 V are estimated to be 8.0 and 2.1 uA W [?] 1 under forward and reverse bias conditions, respectively. The photocurrent generation of the pn heterostructured photodiode is dominantly associated with the transport of the photogenerated charge carriers in the single ZnO NW. Furthermore, the operations of our flexible photodiode are investigated in the upwardly and downwardly bent states, as well as in the flat state. [ABSTRACT FROM AUTHOR]

The photocurrent characteristics of HgTe nanoparticle (NP) thin films fabricated on glass substrates were investigated under the illumination of 1.3 µm wavelength light in this work. The photocurrent obtained from an NP thin film with a vertical structure was 119 µA in magnitude at an applied voltage of 2 V. The magnitude of the photocurrent for an NP thin film with a lateral structure was 23.8 nA at 10 V. Nevertheless, the relative magnitude of the photocurrent measured as a function of the chopping frequency was largely the same for the thin films with both the lateral and the vertical structures. The frequency-dependent photocurrent mechanism of the NP thin films will be discussed in detail in this paper. [ABSTRACT FROM AUTHOR]

Programmable metallization cell (PMC) memory is a kind of next generation non-volatile memory that has attracted increasing attention in recent years as a possible replacement for flash memory. In spite of the considerable amount of research focused on the fabrication of non-volatile memories on plastic substrates with lightweight, thin, and bendable characteristics, there have been few studies on the fabrication of PCM memory on flexible substrates. In this study, we synthesized AgSe nanoparticles (NPs) by a positive-microemulsion method and constructed PMC memories on plastic substrates with programmable layers formed by the spin-coating of the AgSe NPs. To the best of the knowledge, this is the first attempt to construct PMC memory on plastic substrates by the spin-coating of AgSe NPs. The AgSe NPs synthesized in this study had a uniform size of 2 nm and interestingly showed α-phase (high temperature phase) stability at room temperature. Switching behaviors were observed through the voltage scanning on the fabricated memories with applicable switching voltages. However, the resistance ratios of the off-state to the on-state were quite small. The possible reasons for the α-phase stability of the AgSe NPs at room temperature and the detailed memory characteristics will be described in this article. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we demonstrate the photogating effects of p-type HgTe nanoparticles (NPs) on an n-type ZnO nanowire (NW). The photogating effects are due to the charge separation of the charge carriers photogenerated in the NPs under illumination and the subsequent accumulation of the photogenerated electrons in the pn junction of the NPs and the NW. The presence of the electrons in the junction reduces the current in the ZnO NW. The photogating effects are proved by the different photocurrent behavior of the ZnO NW to which the HgTe NPs are attached from that of a bare ZnO NW. In addition, the dependence of the photogating effects on the power of the incident light is discussed. [Copyright &y& Elsevier]

In this study, Si-nanoparticle(NP)/Si-nanowire(NW)-based field-effect transistors (FETs) with a top-gate geometry were fabricated and characterized. In these FETs, Si NPs were embedded as localized trap sites in Al2O3 top-gate layers coated on Si NW channels. Drain current versus drain voltage ( I DS− V DS) and drain current versus gate voltage ( I DS− V GS) were measured for the Si NP/Si NW-based FETs to investigate their electrical and memory characteristics. The Si NW channels were depleted at V GS = 9 V, indicating that the devices functioned as p-type depletion-mode FETs. The top-gate Si NW-based FETs decorated with Si NPs show counterclockwise hysteresis loops in the I DS− V GS curves, revealing their significant charge storage effect. [ABSTRACT FROM AUTHOR]

Silver doped zinc oxide nanowires (NWs) were synthesized on (0001) sapphire substrate by hot-walled pulsed laser deposition. Both enhancement mode and depletion mode NW field effect transistors (FETs) were fabricated. The shift of threshold voltage of silver doped zinc oxide NW FET was observed from 2.45 to -3.2 V depending on the diameter of NWs without any significant changes of the subthreshold swing, carrier concentration, and on/off ratios. We demonstrate that the transfer characteristics of silver doped zinc oxide NW FETs were closely related with the size of NW diameter and control the shift of threshold voltage. [ABSTRACT FROM AUTHOR]

Sintered HgTe nanocrystal-based thin-film transistors (TFTs) with bottom- and top-gate geometries were fabricated at a temperature of 150 °C by spin coating in this work. The SiO2 bottom- and Al2O3 top-gate field-effect TFTs with p channels composed of sintered HgTe nanocrystals exhibit high carrier mobilities of 0.82 and 2.38 cm2/V s, respectively. The operating gate voltages for the top-gate transistor with an Al2O3 dielectric layer are actually lower, compared with the SiO2 bottom-gate transistor. The electrical characteristics of these TFTs are discussed in more detail in this letter. [ABSTRACT FROM AUTHOR]

ZnO nanowires were grown between two Au electrodes on an Al2O3-deposited Si wafer. Photoresponse, photoresponse spectrum, and current–voltage (I–V) studies were performed for the investigation into photoconduction mechanism in these nanowires. The photoresponse of the nanowires under the continuous illumination of light with above- or below-gap energies was slow, which indicates that photocurrent in the nanowires is surface-related rather than bulk-related. The photoresponse spectrum represents the above- and below-gap absorption bands for the photocurrents. The I–V characteristics under the illumination of the above-gap light are ohmic, but the characteristics under the illumination of the below-gap light are Schottky. This observation indicates that the above-gap light lowers the potential barrier built in the contact between the ZnO nanowires and electrodes, but that the below-gap light does not lower the potential barrier. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Photoluminescence, absorption, and photocurrent measurements were made for a hybrid system of 1-thioglycerol-capped HgTe nanoparticles synthesized by colloidal method to investigate the photocurrent mechanism in this hybrid system. Absorption and photoluminescence spectra taken for the capped HgTe nanoparticles reveal strong exciton peaks in the near-infrared wavelength range. The wavelength dependence of the photocurrent for these capped nanoparticles is very close to that of the absorption spectrum. For the photocurrent mechanism of the hybrid system, on the basis of our experimental results and energy diagram for the 1-thioglycerol-capped HgTe nanoparticles, it is suggested in this letter that holes among electron-hole pairs created by incident photons in the HgTe nanoparticles are transferred to capping 1-thioglycerol while electrons are strongly confined in these nanoparticles and that the holes contribute to the photocurrent flowing in the medium of 1-thioglycerol. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this paper, we describe the feedback and tunneling operations of a dual top gate field-effect transistor (FET) with a p+-i-n+ doped silicon nanowire channel. The transistor functions selectively in either a feedback FET (FBFET) or a tunneling FET mode by modulating the source-to-drain voltage, and it features an outstanding subthreshold swing characteristic of 6.15 mV dec–1 with an on/off current ratio (Ion/Ioff) of approximately 106 in the feedback operating mode and of 41.3 mV dec–1 with Ion/Ioff of ∼107 in the tunneling operating mode. Moreover, our device in the FBFET operation mode has memory characteristics with a retention time of 104 s and a program/erase endurance up to 103 cycles owing to the positive feedback loop in the channel region. This study demonstrates the promising potential of our devices in the development of multifunctional electronics. [ABSTRACT FROM AUTHOR]

In this study, we propose newly designed feedback field-effect transistors that utilize the positive feedback of charge carriers in single-gated silicon channels to achieve steep switching behaviors. The band diagram, I–V characteristics, subthreshold swing, and on/off current ratio are analyzed using a commercial device simulator. Our proposed feedback field-effect transistors exhibit subthreshold swings of less than 0.1 mV dec−1, an on/off current ratio of approximately 1011, and an on-current of approximately 10−4 A at room temperature, demonstrating that the switching characteristics are superior to those of other silicon-based devices. In addition, the device parameters that affect the device performance, hysteresis characteristics, and temperature-dependent device characteristics are discussed in detail. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the substantial enhancement of the thermoelectric power factors of silicon nanowires (SiNWs) on plastic substrates achievable by field-effect modulation. The Seebeck coefficient and electrical conductivity are adjusted by varying the charge carrier concentration via electrical modulation with a gate voltage in the 0 to ±5 range, thus enhancing the power factors from 2.08 to 935 μW K−2 m−1) for n-type SiNWs, and from 453 to 944 μW K−2 m−1) for p-type SiNWs. The electrically modulated thermoelectric characteristics of SiNWs are analyzed and discussed. [ABSTRACT FROM AUTHOR]

Electrically driven lasing was demonstrated in light-emitting devices composed of n-ZnO and p-Si nanowires (NWs). The ZnO NWs were synthesized by thermal chemical vapor deposition and the Si NWs were formed by crystallographic wet etching of a Si wafer. The p-n heterojunction devices were constructed using the NWs by the direct transfer and dielectrophoresis methods. At an excitation current of 2 uA, the electroluminescence spectrum showed lasing behavior, and this phenomenon was explained by the ZnO-nanostructure-related cavity property. [ABSTRACT FROM AUTHOR]

We construct fully transparent nano-floating gate memory devices on a glass substrate. These memory thin-film transistors consist of channel layers of ZnO films, electrodes of Al/ITO, and floating gate nodes of Al nanoparticles, exhibiting a transmittance of [?] 71% in the visible region. Their electron mobility, on/off ratio, and threshold voltage shift are estimated to be 0.92 cm2 V [?] 1 s [?] 1, about 104, and 3.1 V, respectively. Moreover, their programming/erasing, endurance and retention are characterized in this study. Our study suggests that our memory devices have great potential for realizing transparent systems-on-glass. [ABSTRACT FROM AUTHOR]

Flexible electronic devices which are lightweight, thin and bendable have attracted increasing attention in recent years. In particular, solution processes have been spotlighted in the field of flexible electronics, since they provide the opportunity to fabricate flexible electronics using low-temperature processes at low-cost with high throughput. However, there are few reports which describe the characteristics of electronic devices on flexible substrates. In this study, we fabricated flexible thin-film transistors (TFTs) on plastic substrates with channel layers formed by the spin-coating of ZnO nanoparticles and investigated their electrical properties in the flat and bent states. To the best of our knowledge, this study is the first attempt to fabricate fully functional ZnO TFTs on flexible substrates through the solution process. The ZnO TFTs showed n-channel device characteristics and operated in enhancement mode. In the flat state, a representative ZnO TFT presented a very low field-effect mobility of 1.2 x 10[?]5 cm2 V[?]1 s[?]1, while its on/off ratio was as high as 1.5 x 103. When the TFT was in the bent state, some of the device parameters changed. The changes of the device parameters and the possible reasons for these changes will be described. The recovery characteristics of the TFTs after being subjected to cyclic bending will be discussed as well. [ABSTRACT FROM AUTHOR]

A technique to implement silicon nanowire (SiNW)-based tunneling field-effect transistors (TFETs) on flexible plastic substrates is developed for the first time. The p-i-n configured Si NWs are obtained from an Si wafer using a conventional top-down CMOS-compatible technology, and they are then transferred onto the plastic substrate. Based on gate-controlled band-to-band tunneling (BTBT) as their working principle, the SiNW-based TFETs show normal p-channel switching behavior with a threshold voltage of [?]1.86 V and a subthreshold swing of 827 mV/dec. In addition, ambipolar conduction is observed due to the presence of the BTBT between the heavily doped p+ drain and n+ channel regions, indicating that our TFETs can operate in the n-channel mode as well. Furthermore, the BTBT generation rates for both the p-channel and n-channel operating modes are nearly independent of the bending state (strain = 0.8%) of the plastic substrate. [ABSTRACT FROM AUTHOR]

The transfer of charge carriers, photogenerated in nanoparticles (NPs), into a single nanowire (NW) is demonstrated in this study by conducting a careful comparison of the optoelectronic characteristics of a ZnO NW with ZnO NPs attached to its surface, a bare ZnO NW and a film of close-packed ZnO NPs. Under the illumination of an above-gap light, the photocurrent taken from the NW with the NPs is remarkably higher in magnitude than that obtained from the bare NW, although the photocurrent is substantially lower for the close-packed NPs. The presence of the absorption band of the NPs in the photoresponse spectrum taken from the NW with the NPs reveals that the transfer of the charge carriers photogenerated in the NPs into the NW dramatically enhances the magnitude of the photocurrent flowing in this NW. Nevertheless, during the transfer, the charge carriers experience trapping and detrapping at the interfaces of the NPs and the NW. [ABSTRACT FROM AUTHOR]

Electrical characteristics of NOT and NAND logic circuits fabricated using top-gate ZnO nanowire field-effect transistors (FETs) with high-k Al2O3 gate layers were investigated in this study. To form a NOT logic circuit, two identical FETs whose Ion/Ioff ratios were as high as [?]108 were connected in series in a single ZnO nanowire channel, sharing a common source electrode. Its voltage transfer characteristics exhibited an inverting operation and its logic swing was 98%. In addition, the characteristics of a NAND logic circuit composed of three top-gate FETs connected in series in a single nanowire channel are discussed in this paper. [ABSTRACT FROM AUTHOR]

Transparent and flexible thin film transistors (TFTs) with channel layers composed of sintered HgTe nanocrystals were fabricated on top of UV/ozone treated plastic substrates and their electrical properties were characterized. A representative TFT with a channel layer composed of sintered HgTe nanocrystals revealed typical p-type characteristics, an on/off current ratio of [?]103 and a field-effect mobility of 4.1 cm2 V[?]1 s[?]1. When the substrate was bent until the bending radius of the substrate reached 2.4 cm, which corresponded to a strain of 0.83% that the HgTe thin film experienced, the TFT exhibited an on/off current ratio of [?]103 and a field-effect mobility of 4.0 cm2 V[?]1 s[?]1. [ABSTRACT FROM AUTHOR]

The 1.54 μm Er[sup 3+] photoluminescence excitation (PLE) and photoluminescence (PL) spectra of erbium-doped silicon-rich silicon oxide (SRSO) are investigated. Between 350 and 820 nm, PLE spectra are broad and featureless, and the PL spectra are independent of the excitation wavelengths. The results indicate that in erbium-doped SRSO, the Er[sup 3+] luminescence is dominated by a single class of Er sites with a strong coupling to all the carriers in the silicon nanograins. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]