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Semiconducting oxide nanoparticles are strongly influenced by surface-adsorbed molecules and tend to generate an insulating depletion layer. The interface between a noble metal and a semiconducting oxide constructs a Schottky barrier, interrupting the electron transport. In the case of a Pt catalyst supported on the semiconducting oxide Nb-doped SnO

Toward the widespread use of polymer electrolyte fuel cells (PEFCs) in electric vehicles, the improvement of the durability and enhancement of the cathode catalyst activity for the oxygen reduction reaction (ORR) are needed. Pt catalysts loaded on graphitized carbon black (Pt/GCB) are promising candidate catalysts with high durability and activity, but the carbon itself has not been able to completely withstand corrosion at high potential. Our group reported that Pt catalysts loaded on Nb-doped SnO2 (Pt/Nb-SnO2), without any carbon additive, showed high electronic conductivity, high ORR activity and high durability (startup/shutdown, load cycling) in membrane electrode assembly (MEA) measurements [1-6]. In the case of a noble metal such as Pt loaded on semiconducting Nb-SnO2, a Schottky barrier would be constructed at the interface between Pt and Nb-SnO2, which tends to decrease the electronic conductivity and electrochemical activity. The electronic conductivity of Pt/Nb-SnO2 with fused-aggregate network structure is enhanced by heat-treatment and high Pt loading (>10 wt%) to equal that of carbon black. XPS spectra for the Pt/Nb-SnO2 catalyst showed that a slight amount of Sn was detected (Fig. 1). The STEM-EDX elemental line analysis indicated that the Sn diffused into the Pt catalyst. We considered that a PtSn interlayer was inserted in the interface between Pt and Nb-SnO2, which would mitigate the effect of the Schottky barrier, induce the electron donation from Pt to Nb-SnO2 and enhance the electronic conductivity. The low cell resistivity of an MEA using our Pt/Nb-SnO2 cathode, as low as that using a Pt/CB cathode, is ascribed to both the enhancement of the electronic conductivity and the construction of electronic conducting pathways by the fused aggregate network structure. Nafion® ionomer film was found to cover uniformly on the hydrophilic surface of the Pt/Nb-SnO2 (Fig. 2), in contrast to the poor coverage of the ionomer on the hydrophobic surface of the Pt/GCB, based on an evaluation with low acceleration voltage transmission electron microscopy. The thin, uniform coverage of the Nafion® ionomer on the Pt/Nb-SnO2 surface helps to construct a membrane electrode assembly (MEA) with low volume ratio of Nafion® to Nb-SnO2 (I/S < 0.20), which increases the apparent mass activity (@ 0.80 V) while maintaining a low Tafel slope by mitigation of the oxygen diffusion overpotential in the Nafion® film with increased porosity in the catalyst layers. This work was partially supported by funds for the “Superlative, Stable, and Scalable Performance Fuel Cell” (SPer-FC) project from the New Energy and Industrial Technology Development Organization (NEDO) of Japan, and JSPS KAKENHI Grant Number 17H03410 from the Ministry of Education, Culture, Sports, Science and Technology. K. Kakinuma, Y. Chino, Y. Senoo, M. Uchida, T. Kamino, H. Uchida, S. Deki, M. Watanabe, Electrochim. Acta, 110, 316 (2013). Y. Senoo, K. Kakinuma, M. Uchida, H. Uchida, S. Deki, M. Watanabe, RSC Adv., 6, 321800 (2014). Y. Chino, K. Taniguchi, Y. Senoo, K. Kakinuma, M. Watanabe, M. Uchida, J. Electrochem. Soc., 162, F736 (2015). Y. Chino, K. Kakinuma, D.A. Tryk, M. Watanabe, M. Uchida, J. Electrochem. Soc., 163, F97 (2016). K. Takahashi, R. Koda, K. Kakinuma, M. Uchida, J. Electrochem. Soc., 164, F235 (2017). K. Kakinuma, R. Kobayashi, A. Iiyama, M. Uchida, J. Electrochem. Soc., 165, J3083 (2018). Figure 1

We have developed a 10.2-inch WUXGA (1920×RGBW×1200) flexible AMOLED display driven by amorphous oxide TFT backplane on a transparent polyimide film. A bottom-emission white OLED with RGBW color filters was adopted. Integrated gate driver circuits were successfully operated.

We fabricated a transmissive one-side-emission organic light emitting diode (OLED) based on a stripe-shaped cathode. The fabricated transmissive OLED whose panel size is 180 × 90 mm2 showed high transmittance of 68% with the luminance ratio of the bright side to the dark side of 70.

We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin-film transistors (a-IGZO TFTs) on transparent polyimide films against bias-temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0-in. flexible active-matrix organic light-emitting diode was demonstrated with the highly reliable a-IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass-production lines. We believe that flexible organic light-emitting diode displays can be mass produced using a-IGZO TFT backplane on polyimide films.

Threshold voltage shifts of a-IGZO TFTs on plastics against bias-temperature stress were successfully reduced below 0.03 V, equivalent to those on glass substrates. We have developed an 11.7-inch qHD (960xRGBx540) flexible bottom-emission active-matrix organic light-emitting diode (AMOLED) driven by a-IGZO TFT backplane fabricated on a transparent polyimide film.

We have reduced threshold voltage shift of IGZO TFTs processed at 200°C under bias-temperature stress of Vg = 20 V at 70°C for 2000 s to 0.22 V by optimizing IGZO deposition and annealing conditions. A flexible AMOLED display with integrated gate driver circuits has been demonstrated.

A large shift of the localized surface plasmon resonance (LSPR) spectrum of gold nanoparticles was attained by electrochemical oxidation of the nanoparticle surface. This oxidation occurred in the cell, which consisted of a pair of indium tin oxide (ITO) electrodes and water medium between the electrodes. On one side of the ITO electrode, the gold nanoparticles were adsorbed. With the application of a voltage of 5 V to the cell, a spectrum shift as large as 68 nm was obtained. Though the spectrum shift has already been observed by changing liquid crystal (LC) orientation surrounding gold nanoparticles, the size of the shift was not large (11 nm). That was because the variation of the effective refractive index of LC was rather small. Our large shift due to electrochemical oxidation resulted from the large refractive index of Au−O. The electrochemical oxidation was confirmed by XPS analysis of the gold nanoparticles with the LSPR spectrum shift. Other possible mechanisms of the shift such as charge localiz...

We have developed an electrochemical reaction display (ECRD) that can be operated in dual reflective and emissive modes in an entire pixel area of a single device. The ECRD utilizes electrochromic (EC) and electrogenerated chemiluminescence (ECL) reactions. These two electrochemical reactions can be controlled independently by adding a luminescent molecule to a liquid electrolyte of an EC cell with three electrodes. In the reflective mode, the ECRD cell exhibits high reflectance (47%) and high contrast ratio (6:1). In the emissive mode, the cell can show luminescent moving images because of the fast response time (10 ms).

Non-piezoelectric inkjet printing methods, namely, ultrasonic inkjet printing and electrostatic inkjet printing have been used for fabricating an all-solution-processed organic thin- film transistor. Silver nanoparticle ink is patterned to form source/drain electrodes using the electrostatic inkjet method and high-viscosity poly(3,4-ethylenedioxythiophene) doped poly (styrene sulfonate) (PEDOT:PSS) was patterned as a gate electrode using ultrasonic inkjet printing. Polymer insulator and polymer semiconductor are spin-coated as a gate dielectric layer and a semiconductor layer, respectively. This is the first fabrication of all-solution-processed organic transistor using non-piezoelectric inkjet printing.

Some new electron-beam projection lithography techniques have been proposed after cell projection (CP) lithography. To make these lithography techniques practicable, development of the stencil mask is an indispensable key technology. Due to reduction in mask magnification, requirements for the stencil mask becomes sever in comparison with that for CP lithography. For example, the stress of the membrane with mask pattern must be controlled within 10 MPa in terms of the pattern image placement (IP) accuracy, and the membrane thickness must be 2 /spl mu/m or thinner from a viewpoint of the pattern aspect ratio. To solve these issues, we developed a new mask substrate with a CrNx intermediate etching stopper, and found that the CrNx material had an etching selectivity of over 1000 enough for the backside etch process. In addition, the internal stress of the CrNx layer can be easily controlled within /spl plusmn/20 MPa by deposition condition adjustment. Also, by using the CrNx stopper layer, membrane warping during the mask fabrication process did not occur. As a result, mask productivity was greatly improved.

The structural and electronic properties of the Li1+xV3O8 insertion electrode, where 0 ≤ x 0.1 with nearly stoichiometric oxygen atoms, small polarons exist without carrier-creation energy at high temperatures, while at low temperatures the conduction may be of variable-range hopping (VRH) type. For x > 0.2, one-dimensional magnetic properties appear due to sizable exchange couplings and order–disorder effects of additional Li ions may lead to significant change of transport properties. For the intermediate composition 0 < x ≤ 0.1, strong randomness of the Li doping and the congenital oxygen deficiency cause VRH states even at high temperatures.

A 70 mm × 80 mm OLED lighting panel with efficacy of 78.6 lm/W at 1000 cd/m2 has been demonstrated. We improved the efficacy of the panel by decreasing driving voltage. We adopted two approaches: optimize device structure by using high-mobility electron transport layers and improve luminous uniformity by embedding metal bus lines.

Triplet harvesting is a candidate technology for highly efficient and long-life white OLEDs, where green or red phosphorescent emitters are activated by the triplet-excitons diffused from blue fluorescent emitters. We examined two oxadiazole-based electron transport materials with different horizontal molecular orientation as a triplet-exciton diffusion layer (TDL) in triplet-harvesting OLEDs. The device characteristics and the transient electroluminescent analyses of the red phosphorescent emitter showed that the triplet-exciton diffusion was more effective in the highly oriented TDL. The results are ascribed to the strong orbital overlap between the oriented molecules, which provides rapid electron exchange (Dexter energy transfer) in the TDL.

A new type of the nutrient sensor using ISFET (ion-sensitive field-effect transistor) has been investigated. Measuring the ion concentration of a solution in plant growh media (ex. rockwool) is difficult and has not been carried out in practice. The authors anticipated that an ISFET, with its advantages of small size and low output resistance, could be used to measure the ion concentration of such a solution in growth media. In this study, the authors examined the basic characteristics of ISFET-based nutrient sensor probes in rockwool as follows : 1) response characteristics for nitrate ion concentration changes in rockwool, 2) reproducibility of the output when they were inserted into rockwool repeatedly, 3) output dependence on the rockwool water content, 4) output dependence on the distance between the ISFET and a reference electrode, 5) long-term stability of the sensitivity and output baseline in rockwool. These experiments have shown that the sensors have sufficient stability for use in this kind of measurement. The authors have found that ISFETs are able to measure the ion concentrations for a nutrient solution in growth media such as rockwool.

Large shift of localized surface plasmon resonance (LSPR) spectrum of gold nanoparticles was attained by electrochemical oxidation of the nanoparticle surface. This oxidation occurred in a cell consisting of a pair of indium tin oxide (ITO) electrodes with water medium between the electrodes. On one side of the ITO electrode, the gold nanoparticles were adsorbed. The LSPR spectrum was moved consecutively to the red by increasing the applied positive voltage. By the application of 5 V to the cell, the spectrum shift as large as 55 nm was obtained. Though the spectrum shift has already been observed by changing liquid crystal (LC) orientation surrounding gold nanoparticles, the amount of the shift was not large (11 nm). That was because the variation of the effective refractive index of LC was rather small. Our large shift due to electrochemical oxidation resulted from the large refractive index of Au-O. The upper limit of the LSPR spectrum shift by our method is estimated to be 138 nm.

A backside contact-type ISFET was developed applying a silicon-insulator-silicon (SIS) structure. A round etching procedure for edges of both silicon islands and backside contact wells enabled adequate photoresist mask layers on them, which were essential to the entire chip fabrication process. FETs formed on the chip have flat gate configurations, and they were insulated from each other and also from the side walls of the chip with a silicon dioxide layer. Making the most of this feature, the chips were encapsulated into flat contact type test probes, using a simple cast molding of three different resins. The gate leakage currents for the probes were under 10 −11 A, which showed that the insulation of the SIS structure and the encapsulation were satisfactory. The leakage current changes for the probes were checked by elapsing in boiling water. The test results suggested that an ISFET probe, which can be sterilized in boiling water and has mechanical strength, would be available.

It is known that the 124 phase Y-Ba-Cu-O superconductor is stabler on heating rather than that 123 phase. Many studies reported that 124 phase was formed in high pressure oxigen atomosphere. In order to form the phase at ordinary pressure, the alkali carbonate has been used as catalysts. So it has been difficult to prepare the long tape.We succeeded in preparing the 124 phase Y-Ba-Cu-O superconducting thick film on Ag tape by pyrolysis of organic acid salts at ordinary pressure. The length of the tape was about 6m. The superconducting tape had 80K of Tc onset, 70K of Tc endpoint, and 2×104A/cm2 of Jc at 4.2K.We confirmed the increases of Tc of Ca-substituted sample in the same process.

Optical properties of poly-crystalline (beta) -SiC membrane deposited by LPCVD have been investigated in detail. The SiC films have a high refractive index value of 2.63 and a low extinction coefficient (k) of 0.0065 at wavelength of 633 nm. Optical transmittance increased as the SiC surface roughness decreased. Peak transmittance at 633 nm for 1.0 micrometers -thick polished SiC membrane with extremely smooth surface of 2 nm Rmax is limited to 83% due to the absorption of the membrane. The transmittance of the polished SiC membrane has increased up to 86% due to reduction in k after annealing at 1050 degree(s)C. Al 2 O 3 film was the most suitable for the SiC film among anti-reflection (AR) materials studied. The attained transmittance values at 633 nm for the as-deposited, the polished and the annealed SiC membranes of 1.0 micrometers in thickness with Al 2 O 3 AR films were, 83%, 88% and 91%, respectively.

We have investigated the effects of film thickness, anti-reflective (AR) coating and surface roughness on the optical transparency of silicon carbide (SiC) membrane. Peak transmittances monotonously increased as the thickness decreased. The transmittance at 633 nm for 1.05 micrometers thick SiC membrane adjusted by reactive ion etching was 70%, and increased up to 80% by an AR coating. SiC membrane with extremely smooth surface of 0.12 nm (Ra) has been obtained by polishing, and had peak transmittances of 69% and 80% at 633 nm for 2.0 micrometers and 1.0 micrometers in thickness, respectively. Poly-crystalline (beta) -SiC membrane in the suitable tensile stress range of 0.3 to 2.0 X 108 Pa and with high Young's modulus of 4.5 X 1011 Pa has been prepared by a hot wall type low pressure chemical vapor deposition, and been found to need to have thickness over 0.7 micrometers to maintain sufficient mechanical strength in processing.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Many properties of LPCVD SiC film as X-ray mask membrane have been investigated in detail. The film has an atomic ratio of 1.0 and negligible impurities, and was found to be damage-free to SR X-rays up to 500 KJ/cm2. An integrated transparency of 1.05 μm thick SiC membrane for SR X-rays was measured to be 76%. The interference peak at 633 nm of optical spectrum has given the membrane of around 1.0 μm in thickness the transmittance peak of 70% and increased to more than 80% after an AR coating or planarizations by polishing and etching-back. The attainable transmittance was found to be limited to about 84%, theoretically and experimentally, due to the absorption of the membrane. The peak transmittance of 87% is obtainable by the AR coating on the polished SiC membrane. The internal stress was found to be independent of thicknesses above 0.6 μm and the measured Young's modulus is 4.5×1011 Pa irrespective of the thickness and stress. Some extremely polished (0.1 nm Ra) and all the etched-back membranes studied withstood breakage at the pressure as high as the as-deposited ones. The stress uniformity in 30 mm square of the membrane was found to be ± 10 % by measuring five local stresses with a bulge method.

We demonstrated high-brightness large-area, white organic light-emitting diode (OLED) consisting of printing-processed organic semiconductor layers. Meniscus printing process was applied to the substrate with 2 μm-high stripe-shape auxiliary electrodes. The OLED panel showed white emission all over the whole emitting area of 58 mm × 52 mm, high average luminance of 10,000 cd/m2, luminance uniformity of 40 %, and high luminous flux of 95 lm.

We have made a prototype of flexible display system integrated with bend-input function. It consists of flexible display, flexible backlight unit with bending sensor, and MPU connected to PC. Zooming in/out in Google Earth and paging up/down in PDF files have been successfully done by bending the flexible display.

— A 9-in. full-color polymer-stabilized OCB TFT-LCD with stable bend alignment in the absence of an electric field was developed. The condition of the polymer stabilization, the characteristics of UV-curable monomers, and their influence on the configurations of the polymer network in the cell were studied. Possible models of the configuration were proposed and their relationship to the electro-optical properties was analyzed using a novel simulation method considering the distribution of anchoring effects from both alignment surfaces and the polymer network. It was suggested that a good performance such as high contrast ratio and fast response could be expected in the polymer network originating from newly developed monomers composed of multifunctional LC acrylates due to a relatively weak-anchoring effect and presumably its localization near the alignment surfaces. By using the newly developed monomers under the optimized polymer-stabilizing process, a high contrast ratio of 250:1 and fast response nearly equal to that of a conventional OCB cell were achieved.

To improve the efficiency of bend transition in OCB, its anisotropy was analyzed. The transition antiparallel (opposite) to the rubbing direction was significantly fast and this anisotropy remained at low temperatures. We propose two effects of LC shear flow on the anisotropy. Based on a pixel design that takes the anisotropy into consideration, 40% reduction of the initialization voltage in a 3-inch TFT-LCD has been achieved.

Fabrication of electronic devices by printing technique is attracting interest in the expectation of lowering production cost. There is an ongoing work using various printing methods. This paper outlines some of the important aspect of printing in terms of fabricating thin film transistor (TFT) arrays. Appropriate combination of inkjet head and the ink material must be considered. Non-piezoelectric inkjet printing methods, such as ultrasonic inkjet printing and electrostatic inkjet printing are also introduced for fabricating all-solution-processed organic thin-film transistor.

— An ink-jet-printing method applied to the microdeposition of high-viscosity resin, including optimization of phosphor dispersion for light-emitting-diode (LED) packaging was examined for the first time. An ultrasonic ink-jet-printing method was used, in which ink droplets are ejected by a focused ultrasonic beam from a nozzle-less printhead. To fabricate white LEDs, high-viscosity phosphor-dispersed resin was deposited to form an encapsulant dome. Two types of methods to control phosphor sedimentation for color uniformity were examined; one is heating the lead frame during the resin deposition, and the other is hydrophobic surface treatment of the lead frame base enabling the fabrication of a small encapsulant dome. For light direction control, a silicone micro lens was deposited on an encapsulant dome using the ink-jet method. The results show that ultrasonic ink-jet printing is an applicable technique to optimize and modify on-demand optical characteristics of LED devices.

This article describes the fabrication of eight-inch continuous membrane masks with a 15‐nm-thick support membrane for electron projection lithography (EPL). In order to develop an extremely thin support membrane with a tensional stress, two techniques were applied; one is a low pressure deposition process to improve the membrane bulk density, and the other is Si addition during the conventional carbon membrane deposition for improving the atomic distance mismatch between substrate and deposited film, and also to address the membrane volume strain cause by the rise in the tensional stress under the low pressure deposition condition. By using Si-additional techniques, an extremely thin membrane with a tensional stress was formed under the conditions of less than 0.5Pa chamber pressure. Long-term membrane stress stability of Si-added extremely thin membranes were particularly improved. It was less than 3MPa in elapsed times of 400h. The zero-loss electron transmittance for the fabricated 15‐nm-thick membran...

In order to cope with the problems with scanning electron microscopes for semiconductor manufacturing, the ability to measure the focal depth and incident angle of an electron beam is required. A technique for estimating the angle of incidence and the depth of focus has been devised. The main feature of the technique is to employ the specimen with a special pit, which is formed from sidewalls with an accurate tilt angle and a surface structure. In this work, the pit was formed on a (100) silicon-crystal substrate and from four (111) sidewalls with an accurate tilt angle of 54.74° and a step-like surface. The incident angle and focal depth of an electron beam was estimated by using the pit. The estimation result agreed approximately with the expected.

We have studied the lithographic performance of high-performance diamond-like carbon (DLC) membrane masks by demonstrating exposure experiments using Nikon’s electron beam stepper, NSR-EB1A. We estimated the inelastic mean free path of 100keV electrons in a membrane analytically using the measurement results of zero-loss electron transmittance and found it to be about 50nm. We then used this value to find the relationship between membrane thickness and zero-loss electron transmittance. The resolution for high-performance membrane masks is equivalent to that of a stencil mask and was not deteriorated by chromatic aberration due to inelastic electron scattering. Electrons undergoing inelastic scattering did not appear to affect resolution. The nominal exposure dose was proportional to the inverse of zero-loss electron transmittance. We also discussed the optimum membrane thickness in terms of throughput and electron inelastic scattering, focusing on plasmon excitation.

We demonstrate complementary exposure of 70 nm system-on-a-chip (SoC) devices in electron projection lithography using Nikon’s EB stepper, NSR-EB1A, and a high-performance Si stencil mask (4×) fabricated by HOYA. A gate level of the SoC device pattern data called Anaheim was processed for mask fabrication using a 10 PC-clustered hierarchical data processing system in which complementary splitting was executed by the M-Split developed by Selete and ISS. Data processing times and output data volumes of the complementary split and of proximity effect correction were all drastically reduced by using our hierarchical data processing method. We optimized stitching features to compensate for the critical dimension (CD) changes that can occur with stitching errors caused by complementary exposures. The complementary stitching accuracy obtained was better than 20 nm and the CD accuracy was better than 10 nm for 100 nm line and space patterns because of the use of stitching features.

Fabrication of 8 in. high-performance continuous diamondlike carbon (DLC) membrane masks for electron projection lithography is described. The mask substrate materials and structures were optimized by evaluating the lithographic performance of the mask. The optimum mask consists of a sandwich structure, consisting of a thicker DLC scatter/a CrNx etching stopper/and a thin DLC support membrane on a bulk silicon wafer. The internal stress of each film component can be controlled by adjusting the film deposition conditions. A DLC film can be easily etched by oxygen gas, and the CrNx etching stopper has a high etching durability. Highly accurate pattern properties can be obtained while also meeting performance requirements. The critical dimension accuracy of a DLC scatterer was less than ±5% with a 280-nm-feature size in a 135×43 mm field. The electron aperture transmittance of a 44-nm-thick DLC membrane, measured by energy and angular distribution analysis for membrane, was 13 times as high as the 150-nm-thi...

We have improved the M-Split complementary mask pattern split program and our electron projection lithography (EPL) data conversion system to achieve a practical data processing time and data volume. The system was designed to rehierarchicalize the data, flattened after the subfield split, by extracting polygons that all have an identical shape as a cell. The M-Split stress check function was improved by using a normalized bending moment as a criterion. A clustered computing system was used to reduce the data processing time. The processing time for a complementary mask pattern split without rehierarchicalizing was reduced to 57 min by using the stress check function and a ten PC cluster system −3–10 times as fast as with commercially available EPL data conversion systems. We successfully fabricated a full-size 8 in. Si stencil mask consisting of 8000 subfields using the data for an actual 70 nm design-rule system on chip device to demonstrate the effectiveness of M-Split. With a higher performance PC cluster system and the rehierarchicalizing, we expect to further reduce the M-Split processing time to 10 min.

We fabricated an 8 in. stencil mask having the complementary pattern of the 70 nm rule system-on-chip device. The 8 in. stencil mask was realized from the development of a mask substrate fabricated by using the sputtering method to form a scattering silicon membrane and an intermediate stopper layer. The intermediate layer material, which functions as an etching stopper, was CrNx. This material has demonstrated high performance in stencil mask fabrication, which is described in detail. The stress in the CrNx could be controlled within ±20 MPa by adjusting the deposition condition. The deposited silicon membrane stress could be easily adjusted in the range of 0–10 MPa. The etching selectivity, when the substrate backside etching was performed, was over 1000 under the low bias power. When the deep etching process was performed using SF6 and CHF3 etching gases for the mask pattern formation, the Si/CrNx etching selectivity was over 100 under the low bias power condition. The mask substrate, which is made up ...

A high-performance membrane mask for electron projection lithography (EPL) systems is proposed. The design and material selection of the mask described here were carefully executed by considering not only the lithographic performance but also various properties. The mask described in this article consists of a 600-nm-thick diamond-like carbon (DLC) scatter on a DLC membrane 30–60 nm thick. The optimum thicknesses are obtained by calculating angular distributions of the transmitted electrons by our in-house Monte Carlo simulator. It is expected to have an electron transmission of up to 80% and a beam contrast of 100% with an appropriate limiting aperture. A 1-mm-sq membrane of thickness of down to 30 nm could be successfully prepared. The high-performance membrane mask can obtain high resolution and high throughput of the EPL systems simultaneously.