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Volcano-structured double-gate field emitter arrays (VDG-FEAs) were fabricated using the etch-back technique. The fabrication process of the VDG-FEA is simple, and the height (hf) of the focusing electrode relative to the extraction gate electrode is easily adjusted by varying the etch-back time without high-resolution lithography. We have fabricated two types of VDG-FEAs with hf = +220 and 0 nm. The focusing characteristic is controlled by tuning hf. The decrease of the anode current is reduced for the VDG-FEA with lower hf under focusing condition producing the same beam spot size.

Scanning nonlinear dielectric microscopy was used to diagnose doping integrity in a transistor channel. The carrier state at various points in a pn junction was defined as n-type, p-type, or depletion through nonlinear capacitance (dC/dV) profiling and pinpoint capacitance–voltage analysis. Carrier state analysis was applied to the n+/p/n+ transistor channel of structures with different process parameters. An increase in the n+ activation temperature from 800 to 950 °C caused shrinkage in channel length of the p-type region. Decreasing the substrate acceptor concentration from 1018 to 1017 cm−3 caused depletion of the entire channel when the gate length was less than 200 nm.

The combination of electron beam lithography and gold nanoparticle-based detection method is subject to a novel high-resolution approach to detecting DNA nanoarrays. In this work, gold nanoparticle-based detection of DNA hybridization on nanostructured arrays is presented. The nanostructured arrays were created by electron beam lithography of a self-assembled monolayer. Amine groups, which are active moieties and are used for attachment of DNA, were introduced to the nanostructures, and the amine-modified structures were characterized by scanning Maxwell-stress microscopy (SMM) for seeing the modification process. The DNA probe covalently immobilized within the nanostructures was hybridized with a biotinylated target DNA. Streptavidin-gold conjugate was then bound to the biotin, thereby assembling inside the nanostructured arrays. The sequence-specific hybridization was imaged by atomic force microscopy (AFM). On the other hand, the activity of the DNA molecules within the nanostructured arrays was verified by fluorescence microscopy using streptavidin-Cy 5 conjugate instead of streptavidin-gold nanoparticles conjugate. On the basis of fluorescent detection, an alternative method has been developed for detection of DNA nanostructures, which will benefit the development of DNA chips.

An ultrahigh-luminance field-emission display (FED) is designed in which a field emitter array (FEA) and memory function are integrated in every pixel of the display panel. The memory function consists of an emission-control thin-film transistor (TFT), a memory capacitor, a write-enable TFT, and a memory-discharging TFT. The operation mechanism is that the time of luminance of the pixel is made longer by the memory function; thus, luminance becomes higher. In principle, the maximum luminance of such a display is expected to be more than 100 000 cd/m2. The ultrahigh-luminance FED is applicable for daylight-readable displays used in mobile electronic equipment. The authors fabricated a prototype of the ultrahigh-luminance FED using Spindt-type FEA and poly-Si TFT technology. It was confirmed that the luminance of the display panel is controlled by the signal for the memory-discharging TFT, which means that the luminance can be dynamically controlled by the input signal. The maximum luminance of 1700 cd/m2 was achieved at a relatively low anode voltage of 1.5 kV. The higher luminance can be expected by applying higher anode voltage.An ultrahigh-luminance field-emission display (FED) is designed in which a field emitter array (FEA) and memory function are integrated in every pixel of the display panel. The memory function consists of an emission-control thin-film transistor (TFT), a memory capacitor, a write-enable TFT, and a memory-discharging TFT. The operation mechanism is that the time of luminance of the pixel is made longer by the memory function; thus, luminance becomes higher. In principle, the maximum luminance of such a display is expected to be more than 100 000 cd/m2. The ultrahigh-luminance FED is applicable for daylight-readable displays used in mobile electronic equipment. The authors fabricated a prototype of the ultrahigh-luminance FED using Spindt-type FEA and poly-Si TFT technology. It was confirmed that the luminance of the display panel is controlled by the signal for the memory-discharging TFT, which means that the luminance can be dynamically controlled by the input signal. The maximum luminance of 1700 cd/m2 w...

In order to control electric field relaxation at the tips of practical emitters, we found that volcano-structured double-gated field emitter arrays (VDG-FEAs) could be improved by placing the focusing electrode 470 nm below the electron extraction electrode. We demonstrated that this approach enables excellent endurance in terms of focusing potential, and confirmed its superior focusing characteristics. Even under strong focusing operation at a focusing electrode voltage of 5 V, this VDG-FEA maintained the anode current of 1.9 ?A, which was 5 times larger than that of the VDG-FEA with the same height of the focusing and electron extraction electrodes.

By adding a memory function to each pixel of a field emission display (FED), an ultrahigh luminance FED with a luminance of more than 10000cd∕m2 can be realized. For this purpose, the authors fabricated a field emitter array (FEA) with a memory function, in which a FEA, emission-control thin-film transistor (TFT), memory capacitor, and write-control TFT are monolithically integrated. They used an HfC-coated Si tip for the FEA because it enables a long emission lifetime. The TFT structure was optimized to control the emission current. The memory-function FEA was demonstrated in a vacuum chamber. The data holding time of the memory function was also measured. It was sufficiently long for display applications.

The HfC-coated Si field emitter arrays (FEAs) controlled by built-in poly-Si thin-film transistors (TFTs) were fabricated. The FEAs were fabricated at a relatively low temperature using Ar-ion-sputter sharpening so that a low-temperature poly-Si TFT process can be applied. A HfC thin film was coated on emitting tips for improving emission lifetime. An emission control TFT having a conventional top-gate structure was fabricated using ion implantation and activation annealing. A combination of multigate and lightly doped drain (LDD) structures was effective at reducing leakage current at a high source-drain voltage. We fabricated a HfC FEA integrated with a TFT having four gate electrodes with a LDD structure. Complete control of FEA emission current by built-in TFT was demonstrated in a vacuum chamber. The detailed fabrication process and emission control characteristics are reported.

Work function control of metal transistor gates was implemented with Al–Ni alloys. In addition to obtaining conventional capacitance-voltage (C-V) measurements to evaluate the work function, we microscopically characterized the work function distribution through scanning Maxwell-stress microscopy (SMM). The C-V curves of the Al–Ni alloys that we investigated exhibited work functions approximately between those of Al and Ni. The SMM analysis revealed that an Al–Ni alloy fabricated by the interdiffusion of a Ni∕Al stack had a significant nonuniformity of the work function. This nonuniformity correlated with degradation of the C-V characteristics for interdiffused Al–Ni alloys.

Volcano-structured double-gate field emission display (VDG-FEA) is fabricated by etch-back technique. Electron trajectories from VDG-FEA are roughly calculated using charged particle trajectories simulation program SIMION.