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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.

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.

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.

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.

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.

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.