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There is no objection that Mean to Target (MTT) and Uniformity of CD (Critical Dimension) are the most important parameters to confirm the quality of mask. So process engineer try to improve these value and metrology engineer have been struggled to provide the accurate and repeatable CD information. One of method for this goal is auto-measurement with job from pattern design. Auto-measurement helps to remove error from human and improve reproducibility of CD. The recent tools are capable to interface with marking generation program so we can measure with auto-marked job without any manual measurement. However, the enhancement design rule of lithography requests the smaller CD size and more complicated pattern layout. These worst factors can be brought about inaccurate CD result due to wrong measurement job from auto-marking program. Therefore metrology engineer have to consider more optimized auto-measurement methodology as well as to use the most advanced measurement tool. In this paper, we are focused on the CD measurement methodology which is the optimized measurement condition according to pattern shape by using the advanced marking parameter when generate auto-measurement job. In order to find the best condition, we designed test patterns containing OPC (Optical Proximity Correction) and printed on the plate. And we made two types of auto-measurement jobs. One is applied with the advanced marking parameters and the other is applied with the normal marking parameters. We measured the plate with these two jobs for each test item on LWM9000. Finally, we compared results from advanced and normal parameter and calculate how much CD can be different for each test item. Through the test result, we can find the best measurement parameter for each kinds of pattern and get more accurate CD result.

Personal robot is robot that live and helps human from space such as human. Personal robot intends rescue that can use assembling various module according to user's inclination or usage as is different from existent industrial robot that take charge repeated work being fixed. Because mixed module that have various structure to one platform, it acts to decentralized system. Therefore, it need technical development to accommodate these structure by use of network interface of change of distributed environment and various rescue in center concentration Computing environment. Research for middleware is studied vigorously to accommodate this different kinds of systems and heterogeneous network It need technical development to accommodate these structure by use of network interface of change of module based Robot and various rescue in center concentration Robot. Research for robot middleware is studied vigorously to accommodate heterogeneous O/S, network, and Platform. Single network connection between modules improves relativity for network. Personal robot is more important service between modules than network connectivity. Therefore, multiplex connection between modules lowers relativity about network connection, and come fault tolerant between module and raise service QoS. We propose architecture that will provide service independently with connection of network interface to user. The proposed Architecture accommodates various connection structure (ex, duplex connection structure) of selfishness species network etc.. in module based Personal Robot middleware. Module Agent that proposed structure composes network 1:1 connection, routing and multiplex service between modules through Synapse Agent possible connection structure have.

This paper proposes an edge-and-corner-directed interpolation for image rescaling. While edge-only-directed interpolation reconstructs edges very well over traditional imag e interpolation methods such as bi-linear or bi-cubic, it often produces critical artifacts, if there is a corner where two or more edges sharply join. In our method, we first try to find a global linear edge direction in a given n * n window. If it fails, we divide the window into 4 sub-windows and try to find an edge direction in each sub-window to determine whether corner exists. The results show that new interpolation preserves the crispiness of edges and improves the overall perceptual image quality as well. Keywords: rescale, edge-based interp olation, image processing 1. INTRODUCTION Although the resolution of digital device is rapidly increasing these days, digital photography still suffers from resolution limits when we want to enlarge a small picture. Actually, digital image rescaling is pursuing two contradictory goals: minimizing jagged line effect and minimizing blurring. It is widely believed that edges play the important role when we evaluate the perceptual quality of resized images, and several edge-directed approaches have been proposed to soothe unwanted effects by preserving and reconstructing edges [1,2,3]. Edge-only-directed interpolation generally produces crispier edges over traditional interpolations such as bi-linear or bi-cubic [3], but it creates unacceptable artifacts, such as noisy spots, disconnected lines and unwanted text ure, where multiple edges are joined or covariance matrices are almost singular as shown in Figure1.[4] The original picture was taken from Kodak photo CD. Edge-only-directed interpolations work very well where only one directional edge exists in a small window. That is, if only one orientation exists, it fills the missing ga ps by interpolating along the edge direction and not across. However, if there are multiple edges, which have distinct directions, in a small window, the interference between edges makes it hard to calculate the accurate glob al edge direction. Thus, we need to ta ke additional steps to consider corners, which are formed by two or more sharply joining edges. In this paper, we will address a new approach to compensate for blurring and aliasing effects using edge and corner cues. The rest of this paper is organized as follows: Section 2 explains the new edge-and-corner-directed interpolation in detail. Section 3 reports some results and comparisons of inte rpolation methods applied to real images, and in Section 4, some concluding remarks are presented.

We developed blob feature analysis-based real-time marker-free motion capture system. Our system can capture actor’s end-effectors and reconstruct 3-dimensional human motions in real-time without any attaching markers or sensors. To capture robustly various motions of an actor, we proposed blob feature models such as shape model, color model, and spatial model for end-effectors such as a head, hands, and feet. And we introduce weights for each model. According to the clothing conditions of an actor, the proposed method adjusts weights for each model automatically. So, our system can detect and distinguish the actor’s end-effectors although the shapes and the color of end-effectors vary due to various poses and the variation of illumination. And our models are very simple to compute, therefore, the motion capture can be real-time process. Experiments are conducted on a lot of people wearing various clothes under general fluorescent lights. The proposed system can reconstruct actor’s various motions at 30 frames per second with the 99.95% success rate of the detection of an actor’s end-effectors. So, we confirmed that the proposed motion capture system could stably reconstruct motions of a lot of people wearing various clothes in real-time.

The move towards smaller feature size continuously requires more accurate lithography models. Part of models improvement comes from a better understanding of involved physics and chemistry. State of the art models assume development rate to be dependent on level of de-protection of resist film while development kinetics is not taken into account. Model refinements consist in getting a good model of development rate versus de-protection level. Recent studies have put in evidence the importance and the influence of development kinetics. Based on this, a new development process concept has been developed: the Proximity Gap Suction Development (PGSD). This paper presents a parallel approach to PGSD using megasonic agitation in order to improve development process understanding. Analysis has been performed by focusing on microloading effect characterization, also taking into account Critical Dimension (CD) linearity, CD iso-dense bias. Interpretation and analysis were achieved through use of DOE techniques. Results are then discussed with respect to previous PGSD studies but also to current development models. It is believed that improvement of development process could be also achieved in wafer making through the use of high flow rate development techniques such as PGSD or megasonic development.

Recently there has been significant interest in the using of chemically amplified (CA) resists for the mask making industry because of their high sensitivity, high contrast, and good dry etch resistance. Especially positive CA resists with high acceleration voltage E-beam systems are being become the main stream of making for advanced masks. However, the positive CA resists often make the issue of the CD uniformity degradation by the fogging effect at a high acceleration voltage (50keV) E-beam writing tool as writing for masks, which are having a high pattern density. In previous our paper, we have already confirmed that a positive CA resist shows the CD uniformity error more than 30nm by the fogging effect at the mask which is having above 40% pattern density, even if its CD uniformity error value is smaller than 50nm of ZEP. In this paper, we have described and studied for the performances of the negative CA resist at the 50keV e-beam writing tools in advanced mask making like logic device with high pattern density and we have compared with a positive CA resist at the 50keV e-beam writing tools. Furthermore, We have confirmed that the negative CA resist have an advantage what is in advanced mask making process like logic device masks with high pattern density at 50keV e-beam writing tool and they have been compared with the positive CA resist.

Phase Shift Masks (PSMs) have been widely used in the photomask industry for nowadays. Among several types of PSMs, Alternating Aperture PSM (AAPSM) allows for better resolution within other advantages. This paper deals with micro-trench formation during quartz etching. Micro-trench can produce distortion of the light intensity and lead unwanted results on wafer. Several experiments are performed with respective etch conditions; fluorine (F) gas species, gas flow rates, bias powers, and substrate temperatures while other conditions are fixed. Quartz etching is processed with Inductively Coupled Plasma (ICP) system. Etched morphologies are observed by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and a surface profiler to select the best condition as functions of etch parameters. Results show that bias power is the most important factors to decide quartz surface morphologies. Finally, mask image is simulated by AIMS system under given condition.

As the CD specification on Masks is getting more tighten, the fogging effect by re-scattered incident electron at a high acceleration e-beam system and the loading effect at dry etching step due to pattern density are current critical issues for mask making. These give rise to the variation of mean CD value and the degradation of global CD uniformity. So we have to correct these effects accurately in order to meet the CD specification for design rule 0.15um or below devices. In this paper, we have applied a new positive CA (chemically amplified) resist from Fuji Film Arch co., It was written at 50 kV variable vector scan E-beam system and we tried to classify the CD error by the fogging and loading effect, respectively. Also we have compared with ZEP7000 resist, non-CAR positive type, which is used widely for conventional e-beam mask making to assess the CAR performance, especially in terms of CD error causing by the fogging effect. Through this comparison test, we found that the CD error due to the fogging effect shows somewhat different value according to resist type and writing strategy even though use same exposure dose. In this paper, we have assumed that such results are due to the difference of dose latitude. Dose latitude is different as intrinsic contrast value of each resist and writing strategy such as writing pass, should affect on beam profile (dose profile), it can also change pattern profile of resist and it can finally cause a dose latitude difference. Finally, we have evaluated for CD mean error and uniformity error by fogging and etch loading as open ratio changing, respectively.

ArF lithography that is expected the candidate for next generation optical lithography and attenuated Phase Shift Mask (att-PSM) will be adapted for 0.12micrometers design-rule and beyond. For the next-generation lithography, the most important requirement for mask process is enough resolution and good pattern fidelity to generate various critical patterns, of which sizes are below 0.5micrometers main pattern including OPC patterns. In this paper we describe in terms of blank mask properties, mask making process and wafer performance of ArF attenuated Phase Shift Mask (att-OSM) using TiN/Si 3 N 4 (abbreviated as TiN/SiN) multi-layer for Next Generation Lithography (NGL). In view point of material, we have evaluated for the applicability of TiN/SiN multi-layer to ArF lithography as compared with non- stoichiometric MoSiON-based single-layer structure. In mask making process, we used Chemically Amplified Resist (CAR) process characteristics and Dry etching system for improvement of enough resolution and pattern fidelity. Also we have investigated wafer performance for ArF att-PSM in terms of process windows as compared with BIM (Binary Intensity Mask) in 120nm D/R real cell pattern and 100nm L/S(Line and Space)D/R pattern, respectively.

We have developed next generation photmasks with a variety of method and approach including new material, machines and technology. Because enhanced resolution and pattern fidelity are required rapidly in photomask for coping with further advances in optical lithography. Specially Laser Lithography, Alta3500 has low butting error, fast throughput and registration but has a weak point as corner rounding, CD linearity and ID bias against minimum MEEF (Mask Error Enhancement Factor) acquisition and enhanced pattern printability. But we can not help feeling much cost burden and worse productivity problem in the process of advanced photomasks development. Therefore we have to always consider low cost under high precision technology with current machine and material. We need to extend Alta3500 productivity for advanced device and a variety of device types. So we approached Optical Proximity Correction (OPC) among several candidates for helping that kinds of requirement. And we selected Rule Based OPC for helping fast application of correction rule and low mask complexity. We evaluated mainly Serif and Jog pattern for acquiring corner rounding, CD linearity and ID bias improvement at Alta3500. And we made a conclusion that Alta3500 can extend to 0.15(mu) Logic fabrication with implementation of OPC pattern generation. In this paper, details of OPC effects and application for 0.15micrometers devices will be further discussed.

As the wafer design rule is getting smaller, the size and transmittance of the defect on the reticle, especially for the semi-transparent defect, is one of the important factors to be controlled in mask shop. In order to minimize controversy for the accuracy of size and transmittance measurement, we need to define the detection and measurement ability of each inspection machine for the half-tone defect. In this work, we make semi-transparent defects with FIB repair tool, SEIKO, and treat this plate with NaOH. We first investigate the delectability of each inspection machine for the semi-transparent defects according to the size and transmittance increase and accuracy of size measuring tool supported in each inspection machine, KLA, lasertec and ORBOT. We verify the measurement result with CD SEM for the size and AIMS for the transmittance.

In low k1 lithography, reticle quality decides the process capability. Therefore, we must minimize CD errors on the reticle plate. Double Step process (DS process) is a unique method to improve CD uniformity of line patterns on the active region of poly layer reticle. In DS process, poly layer design is divided into the active region and the non-active region. And then, these two regions are processed individually. By using this procedure, pattern density variation across the reticle plate is reduced when making line patterns on the active region. As a result, the loading effect of the dry etching process reduced, and CD uniformity of these patterns can be improved. Using this technique of reticle fabrication, CD uniformity could be improved. Particularly, the range of CD variation of line patterns in logic cells was drastically reduced from 29nm to 20nm.

The patterning potentialities of sub-100nm pattern for ArF lithography was evaluated with conventional alternating PSM (alt-PSM) for dense lines and spaces (L/S) and phase edge PSM (PE-PSM) for isolated lines of memory device. In dense L/S pattern,110nm pattern was defined with relatively small depth of focus(DOF) window(~ 0.2 ?m) due to phase error of mask. As pattern sizes was changed from 130nm to 200nm, critical dimension (CD) difference between two neighboring spaces was varied and it was assumed that micro loading effect was occurred in Qz etching. The linearity was guaranteed to dense L/S of 110nm and isolated line of 90nm, and Iso-Dense bias was controlled within 15nm. The 60nm and 70nm isolated lines of PE-PSM ware defined with good process windows in the case of OA_X size(X-direction size of Cr open area) of 0.5 ?m. The 55nm isolated line was also defined. The pattern shift of isolated lines was occurred with 4~7nm as phase of mask was varies within 190 ~ 200 ° . Though the alt-PSM with high numerical aperture (NA) for ArF lithography was strong candidates for sub-1 OOnm lithography of memory device, the issues of mask fabrication such as tighter phase control and minimizing etch loading effect would be big obstacles. On the contrary, there were many possibilities of sub-100nm patterning in PE-PSM with good process windows, however tighter control of pattern shift due to phase error must be studied intensively.

We investigated the printability of various OPC patterns with different sizes and densities for mask technology below 0.13 micrometers design rule using CAR and 50kV e-beam system. Because of high resolution characteristics of CAR process with high acceleration voltage system, we obtained OPC printability of 0.12 micrometers even in scattering bar type and excellent pattern fidelity. How to design to get required OPC pattern, design guide was considered in this work and discussed the applicability of CAR process to practical manufacturing of OPC masks of 0.13 micrometers design rule or less.

As the required minimum feature size is rapidly down to sub- micron at photomask, the fabrication of alternate lithography techniques to extend and prolong current technology becomes critical important. So recently MoSi PSM are being applied in semiconductor lithography, primarily for high density layers such as found in memory chips. The increasing use of MoSi based attenuated phase shift masks necessitates defect reducing on the MoSi phase shift mask reticles. In this paper, in order to reduce the defect on the phase shift mask reticles, we will discuss the results of several experiments, utilizing CHF3/)2 gas mixture and SF6/He gas mixture chemistries and various process sequences. This paper reports the results of defect reducing for MoSi attenuated phase shifting masks using an inductively coupled plasma system.

ArF lithography which is expected for the next generation optical lithography is adapted for 0.13 micrometers design-rule and beyond. ArF half-tone phase shift mask (HT PSM) will be applied as 1st generation of ArF lithography. Also ArF PSM cleaning demands by means of tighter controls related to phase angle, transmittance and contamination on the masks. Phase angle on ArF HT PSM should be controlled within at least +/- 3 degree and transmittance controlled within at least +/- 3 percent after cleaning process and pelliclization. In the cleaning process of HT PSM, requires not only the remove the particle on mask, but also control to half-tone material for metamorphosis. Contamination defects on the Qz of half tone type PSM is not easy to remove on the photomask surface. New technology and methods of cleaning will be developed in near future, but we try to get out for limit contamination on the mask, without variation of phase angle and transmittance after cleaning process.

We analyzed the local pattern collapse by KLA-2132 in patterning gate line of 0.18 micrometers on the Poly-Si/WSix/Si 3 N 4 , where the thickness variation of Si 3 N 4 (Nitride) film affected on the substrate reflectivity. By thickness split experiments of organic bottom anti- reflective layers (ARLs), we showed the effect of thickness variation of Nitride on the resist pattern collapse. We investigated the contribution of various factors to the pattern collapse. First of all, we focused on the CD variation due to substrate reflectivity variation to remove patterns of tolerable aspect ratio. In order to obtain better CD uniformity by tight reflectivity control considering the thickness variation of Nitride film, we optimized anti-reflective layer process using inorganic ARLs. As an inorganic ARL, we used PECVD SiOxNy:H(SiON) of which optical constants were changed by deposition conditions. We compared typical positive-tone DUV resists, of acetal based with environmentally stable chemically amplified photoresist type, to clarify the effect of resist and organic bottom ARL materials.

This paper discuss a more stable algorithm of rigorous coupled wave analysis applicable to 2-D exposure simulation in an optical lithography. This algorithm can resolve a divergence problem inherentlyand can be implemented as full vector model, easily. 2-D exposure simulator based on this algorithm isdeveloped and be applied successfully to a very thick photoresist system. Intensity distributions insidethe photoresist are simulated and compared with those of other vector models. The adaptive layeringtechnique is introduced to the simulation of bleaching process in order to reduce the computation time. Itis found that the technique can reduce greatly memory size and computation time with a reasonable accuracy.Keywords : lithography, simulation, coupled wave analysis, waveguide method, bleaching, exposure 1. INTRODUCTIONIn conventional lithography simulations, vertical propagation of an aerial image is assumed. Asthe numerical aperture of an optical lithography system increases, however, the oblique propagation oflight in the photoresist affects significantly the PAC distribution of the photoresist. The scattering effectbecomes more significant in the case of printing fine features over topological structures. Therefore, it isdesirable to develop vector simulators based on rigorous theory Recently, several rigorous models havebeen applied to 2—D exposure simulation. These include the finite element method '

Influence ofshape ofthe illumination aperture on the intrafield image displacementByeong-Chan Kim, Young-Jin Song, Hong-Seok Kim, and Jae Jeong KimAdvanced Process Technology Dept., ULSI Research LaboratoryLG Semicon Co., Ltd., Cheongju, 360-480, Rep. of KoreaABSTRACTThe intrafield image displacement with the various illumination apertthes (conventional, quadrupole,annular) was studied andits influence on the actual overlay accuracy was estimated quantitatively. It was found that deviation of the distortioncomponents of modified illumination apertures from conventional aperture (NA 0.57, c 0.6) brought about the overlaybetween conventional and modified illumination-exposed layers within lOnm in the ftill-field (22rnnf). Quadrupole andannular apertures with high oblique illumination ('out>06) showed relatively lower in absolute magnitude of distortioncomponents and narrower in fluctuation span across the field compared to conventional aperture. However, apertures with lowoblique illumination (a0t

The application of attenuated PSM to dense contact array is restricted by intense optical interference of sidelobe peaks around hole pattern which is called proximity effect. In order to reduce the effect of proximity, it is necessary to optimize the transmittance of mask field and the exposing energy which cause mask bias. The vast of data are required for doing above job. Using simulation, however, by sidelobe, E- D curves can not be used directly to find the depth of focus. The criterion for sidelobe was defined to find process window from E-D curve. To reduce sidelobe in dense contact hole array, the auxiliary patterns were placed between holes. By simulations and experiments, attenuated PSM with auxiliary pattern could be applied effectively to the dense contact hole of 64MDRAM.