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Over the years, lithography engineers have continued to focus on CD control, overlay and process capability to meet node requirements for yield and device performance. Previous work by Fukuda1 developed a multi-exposure technique at multi-focus positions to image contact holes with adequate DOF. Lalovic2 demonstrated a fixed 2-wavelength technique to improve DOF called RELAX. The concept of multi-focal imaging (MFI) was introduced3 demonstrating two focal positions are created that are averaged over the exposure field, this wavelength “dithering” approach which can be turned on and off, thus eliminating any potential scanner calibration issues. In this work, the application of this imaging method (1 exposure-2 focus positions) can be used in thick photoresist and high aspect ratio applications. An example of thick photoresist imaging is shown in figure 1. We demonstrate 5um line and space features in 10um of photoresist at 3 different imaging conditions. On the left, single focus imaging (SFI) at best dose and focus, the center image which is also SFI but at a defocus of +3.2um. On the right is MFI with 2 focus positions of 0 and 2.8um. Here we can see a significant improvement in the SWA linearity and image profile quality. A second example of high aspect ratio imaging using MFI is shown in figure 2. The aspect ratio of 13:1 is shown for this. The use of Tachyon KrF MFI source – mask optimization flow will be reviewed to demonstrate optimum conditions to achieve Customer required imaging to meet specific layer requirements.

Anamorphic imaging enables NA=0.55 in future EUV systems. At unchanged reticle size, the maximum on-wafer image size is reduced from the today’s full-field to a half-field of 26mm by16.5mm. Though most of the applications use a chip smaller than a half field, some of them still need a larger chip. To realize an on-wafer full-field with an NA=0.55 EUV system, two half-field images need to be stitched: abutting two images from a single reticle or from two different reticles, depending on the application. Using the ASML NA=0.33 NXE system at imec, “at-resolution stitching” on wafer is used to explore experimentally how CD and pattern placement are affected by abutting images of critical patterns located at the reticle edge. Using various test masks, a pattern placement error is measured within a 10μm range (1x) from the Black Border (BB) edge. Ideally it will be avoided by an adequate mask manufacturing process. We also measure a crosstalk between the two abutting images, that is attributed to a flare crosstalk, impacting the CD of critical patterns. Dummy tiles and a flare OPC need to compensate for this effect similarly to the correction inside the image. Finally, at short range, aerial images of the critical patterns at the very edge of abutting images can crosstalk. To avoid a complex OPC and tight specifications on the BB edge, an exclusion band is recommended to keep those aerial images from interacting. With the adequate placement solution at mask BB edge and with a flare compensation solution implemented, an exclusion band of about 1μm at wafer level is sufficient to support a robust stitching scenario for anamorphic High NA imaging. Its impact on various types of applications is discussed.

The demand for computer-assisted game study in sports is growing dramatically. This paper presents a practical video analysis system to facilitate semantic content understanding. A physics-based algorithm is designed for ball tracking and 3D trajectory reconstruction in basketball videos and shooting location statistics can be obtained. The 2D-to-3D inference is intrinsically a challenging problem due to the loss of 3D information in projection to 2D frames. One significant contribution of the proposed system lies in the integrated scheme incorporating domain knowledge and physical characteristics of ball motion into object tracking to overcome the problem of 2D-to-3D inference. With the 2D trajectory extracted and the camera parameters calibrated, physical characteristics of ball motion are involved to reconstruct the 3D trajectories and estimate the shooting locations. Our experiments on broadcast basketball videos show promising results. We believe the proposed system will greatly assist intelligence collection and statistics analysis in basketball games.

Traveling-wave photodetectors (TWPDs) are an attractive way to simultaneously maximize external quantum efficiency, electrical bandwidth, and maximum unsaturated output power. We review recent advances in TWPDs. Record high-peak output voltage together with ultrahigh-speed performance has been observed in low-temperature-grown GaAs (LTG-GaAs)-based metal-semiconductor-metal TWPDs at the wavelengths of 800 and 1300 nm. An approach to simultaneously obtain high bandwidth and high external efficiency is a traveling-wave amplifier-photodetector (TAP detector) that combines gain and absorption in either a sequential or simultaneous traveling-wave structure.

Ultrahigh-speed photodetectors and printed-circuit antennas construct photonic transmitters. In this letter, we studied the saturation behaviors of an edge-coupled membrane photonic transmitter based on low-temperature-grown GaAs. The saturation behaviors determine the optimized operation condition of photonic transmitters. Ultrahigh external light-terahertz (THz) conversion efficiency of 0.11% was achieved with 645-GHz radiation. According to our knowledge, this value is the highest reported external conversion efficiency of all photonic transmitters with radiation higher than 500 GHz. The high conversion efficiency and the edge-coupled structure of our devices release the power burden imposed on tunable semiconductor laser sources and imply their applications as compact all-solid-state THz radiation sources.

We observed distinct bandwidth degradation behaviors in low-temperature-grown GaAs (LTG-GaAs)-based traveling-wave photodetectors (PDs) under /spl sim/1300-nm telecommunication wavelength operation. Compared with the bandwidth degradation behaviors of different excitation wavelengths (/spl sim/800 and /spl sim/1550 nm) in LTG-GaAs-based PDs, the saturation behaviors at the studied wavelength are more serious and can be attributed to "hot electron" effect of photogenerated carriers. The disclosed unique material properties of LTG-GaAs are important for its applications in ultrafast optoelectronics and understanding its carrier dynamics with the defect states.

Ultra-high-speed photodetectors and printed-circuit antennas construct photonic transmitters. In this letter, we demonstrate a terahertz (THz) photonic transmitter: edge-coupled membrane photonic transmitters based on metal–semiconductor–metal traveling-wave photodetectors, which are fabricated with low-temperature-grown GaAs photoabsorption layers. With a membrane-based and edge-coupled structure, the demonstrated photonic transmitters can eliminate the requirement of Si lenses and attain an over 20 times higher optical-to-THz power conversion efficiency 2×10−4 than vertical illuminated photonic transmitters with Si lenses at the same operation frequency.

A ring isolator is demonstrated for the first time by directly bonding a cerium-substituted yttrium iron garnet (Ce:YIG) onto a silicon ring resonator using oxygen plasma enhanced bonding. The silicon waveguide is 600 nm wide and 295 nm thick with 500-nm-thick Ce:YIG on the top to have reasonable nonreciprocal effect and low optical loss. With a radial magnetic field applied to the ring isolator, it exhibits 9-dB isolation at resonance in the 1550 nm wavelength regime.

We characterize an approach to make ultra-low-loss waveguides using stable and reproducible stoichiometric Si3N4 deposited with low-pressure chemical vapor deposition. Using a high-aspect-ratio core geometry, record low losses of 8-9 dB/m for a 0.5 mm bend radius down to 3 dB/m for a 2 mm bend radius are measured with ring resonator and optical frequency domain reflectometry techniques. From a waveguide loss model that agrees well with experimental results, we project that 0.1 dB/m total propagation loss is achievable at a 7 mm bend radius with this approach.

In this letter, we present the design of an integrated optical isolator realized by bonding a silicon micro-ring resonator with a Ce:YIG garnet. The nonreciprocal phase shift effect induced by applying a radial magnetic field has been studied using the finite-element method; numerical results clearly point out how to optimize the thickness of the silicon ring and Ce:YIG garnet in order to maximize the nonreciprocal effect between the forward and backward TM modes.

We report an approach to make ultra-low-loss waveguides using fixed-index-contrast stoichiometric Si 3 N 4 . A record low single-mode propagation loss of 0.70 ± 0.02 dB/m was achieved while multi-mode designs have fundamental mode loss as low as 0.43 ± 0.04 dB/m.

Commercial applications of video analysis are getting valuable with the development of digital television. People can easily record all kinds of programs and enjoy the videos in their leisure time. Among these programs, broadcasting sports videos are usually more tedious than others since they involve not only the main games, but also break time or commercials. And even main games comprise periods which are not splendid enough for the audience. Therefore, a considerable amount of research focuses on automatically annotating semantic concepts in sports videos, and providing a spellbinding way to browse videos. In this chapter, we briefly introduce related work of video analysis for different kinds of sports, and propose a generic framework for sports video annotation. We explicitly elaborate the state of the art techniques for sports videos analysis. Visual and audio information are utilized to extract mid-level features, and different models for semantic annotation are expounded with practical examples. We also expand on applications of sports video analysis from the viewpoints of the audience, professional athletes, and advertisers.

We investigate the nonlinearity of ultra-low loss Si3N4-core and SiO2-cladding rectangular waveguides. The nonlinearity is modeled using Maxwell's wave equation with a small amount of refractive index perturbation. Effective n2 is used to describe the third-order nonlinearity, which is linearly proportional to the optical intensity. The effective n2 measured using continuous-wave self-phase modulation shows agreement with the theoretical calculation. The waveguide with 2.8-μm wide and 80-nm thick Si3N4 core has low loss and high power handling capability, with an effective n2 of about 9×10(-16) cm2/W.

We characterize an approach to make compact low loss silica on silicon waveguides and achieve good agreement with theory. Record low losses of 8 dB/m for 0.5-mm bend radius down to 3 dB/m for 2-mm bend radius were achieved.

Photographers usually take a shallow focus image to highlight the main subject in the picture and blur the distractions in the background region. Softening these distractions can not only produce special vision effect but also keep the privacy for people in the background. In this work, we develop a brand new defocusing algorithm to simulate the blur effect in the background caused by a wide aperture camera. We also design an easy-to-use interactive interface for user to segment foreground/background objects, adjust the depth of field for images, and assign camera settings. Techniques including lazy snapping, alpha matting, depth information generation and defocusing are integrated in the system. The experimental results show the effectiveness of the proposed methodology.

A convenient video browsing system for popular sports such as baseball, tennis and billiards is proposed in this work. A sports video is automatically segmented into video clips and annotated with semantic concepts in terms of event type. For sports with specific game structure, e.g. baseball and tennis, we further analyze the entire video of the match with the aid of caption information, webcast information, and the domain knowledge of the corresponding sport. Each segmented video clip with semantic annotation is then mapped to a certain part of the game structure. Finally, the proposed system, name as Sports Wizard, provides a favorable way for the user to browse sports videos based on semantic concepts or game structure.

In basketball games, wild-open means that there is an offensive player not well defended by his/her opponents. The occurrence of wild-open usually implies the existence of a successful offense tactic. In this paper, a Wild-Open Warning (WOW) system is designed to assist basketball coaches/players in revealing possible tactics of their opponents through watching the broadcast game videos. The system automatically extracts semantic objects such as the court and the players in the video, and calibrates the players' positions to the real-world court coordinates. A robust and efficient algorithm for court detection and camera calibration is proposed for basketball videos. Wild-open is detected when the position of an offensive player satisfies three predefined criteria. In the mean time, the system will mark the wild-open players to warn the viewers such that they should keep attention to certain players.

Optoelectronic tweezers (OET) [1] has recently emerged as a novel and powerful technique for optical manipulation of microscopic and nanoscopic particles. Previously, OET manipulation and separation of various cell types, polystyrene beads [1,2], and semiconducting and metallic nanowires [3] have been demonstrated. In this paper, we present some of the recent advances in the optoelectronic tweezers technology. In particular, trapping and manipulation of metallic spherical nanoparticles with diameters below 100 nm [4], parallel assembly of nanowires using lateral-field optoelectronic tweezers (LOET) [5], and assembly of InGaAs/InGaAsP multi-quantum well (MQW) microdisk lasers (201nm thick, 6µm in diameter) using LOET [6,7] are discussed.

In this work, we propose a framework to build a billiards tutoring system based on broadcasting nine-ball video analysis. A robust table detection module is developed by mapping the displayed video frames to a predefined billiard table model. In addition, we detect balls and trace their positions at every time instant. The real-world spatial relationships between the table and the balls are used to provide the aiming and position play suggestions. Ball position information is also utilized to distinguish each play into corresponding event by a rule-based method. The experimental results are encouraging and are more comprehensive than existing works of billiards video analysis.

We demonstrate optofluidic assembly of pre-fabricated InGaAsP microdisk lasers (6 µm diameter, 200 nm thickness) on silicon photonic circuits with sub-micron alignment accuracy. The laser output is successfully coupled to the integrated silicon waveguide.

In this paper, we investigate an important but understudied problem, gender classification from human gaits. And we have proved the ability of using GEI (Gait Energy Image) as a representation of human gait for arbitrary view angles. Using GEI as a discriminative feature, we construct angle classifiers and gender classifiers from different approaches. Experiments show that our system achieved a good performance in real-time and is able to be applied to real-world application.

Online photo albums have been prevalent in recent years and have resulted in more and more applications developed to provide convenient functionalities for photo sharing. In this paper, we propose a system named SheepDog to automatically add photos into appropriate groups and recommend suitable tags for users on Flickr. We adopt concept detection to predict relevant concepts of a photo and probe into the issue about training data collection for concept classification. From the perspective of gathering training data by web searching, we introduce two mechanisms and investigate their performances of concept detection. Based on some existing information from Flickr, a ranking-based method is applied not only to obtain reliable training data, but also to provide reasonable group/tag recommendations for input photos. We evaluate this system with a rich set of photos and the results demonstrate the effectiveness of our work.

In this paper, we propose a system for automatically detecting cardiopulmonary resuscitation (CPR) events and analyzing CPR qualities in surveillance videos. The system is further applied to the training of healthcare providers in the emergency room. Instructors could more efficiently evaluate the CPR quality performed by a medical team with the aid of our system. We extract motion vectors in all image blocks, and take motion information as a clue to classify video sequences into CPR and non-CPR segments based on Support Vector Machine (SVM). We further analyze several indicators of CPR quality and attach CPR information to the video. In order not to infringe the privacy of the patient, we apply a mosaic mechanism to mask the skin color regions of the patient. Our system has been applied to several simulated CPR video sequences and the results show acceptable accuracy in CPR detection and CPR information measurement.

A room-temperature optofluidic assembly process to integrate III-V microdisk lasers on a silicon chip is demonstrated. The assembly is accomplished using lateral-field optoelectronic tweezers, which achieves a placement accuracy of approximately plusmn 0.25 mum.

This paper proposes a mining-based method to achieve event detection for broadcasting tennis videos. Utilizing visual and aural information, we extract some high-level features to describe video segments. The audiovisual features are further transformed to symbolic streams and an efficient mining technique is applied to derive all frequent patterns that characterize tennis events. After mining, we categorize frequent patterns into several kinds of events and therefore achieve event detection for tennis videos by checking the correspondence between mined patterns and events. The experimental results show that the proposed approach is a promising way to detect events in broadcasting tennis video.

An InGaAs/InGaAsP microdisk laser is assembled on silicon using lateral-field optoelectronic tweezers, achieving room-temperature pulsed operation with a threshold power of 0.85 mW. The room-temperature assembly enables a post-CMOS process to fabricate micro-lasers on silicon.

A room-temperature optofluidic assembly process to integrate III-V microdisk lasers on a silicon chip is demonstrated. The assembly is accomplished using lateral-field optoelectronic tweezers, which achieves an unoptimized placement accuracy of approximately plusmn 0.25 mum.

A simplified process has been developed to fabricate MEMS tunable microring resonators on six-inch silicon-on-insulator wafers. Deep UV lithography is used to create 220-nm-wide waveguides and microrings. The process is CMOS compatible. The transmission spectra change from a double resonance dip (under-coupling) to a broader single resonance dip (over-coupling) when the waveguide is moved closer to the microring. This is explained by coupled mode theory that includes the effect of backscattering in the microring.

This paper discusses the conversion efficiency and device behavior of an edge-coupled membrane photonic transmitter, which is composed of a high-speed photodetector, a RF choke filter and planar antenna. With a radiation frequency of 645 GHz, the conversion efficiency can be improved higher than 0.1% while this value is a function of optical illumination power, device bias, and antenna design.

Femtosecond carrier dynamics in InGaAsN single quantum well were studied for the first time. Pump-probe measurement shows the enhanced free carrier absorption due to highly excited carriers with a delayed carrier cooling time around 2/spl sim/3.7ps.

Strong electric-field-induced-second-harmonic-generation effect was observed in bulk lithium niobate. We utilize this effect to map three-dimensional electric field distribution with high spatial and temporal resolutions.

Summary form only given. As a result of the wide use of electronic and optoelectronics devices, the need for an efficient tool to characterize integrated circuits (IC) is growing up. Electric-field-induced-second-harmonic-generation (EFISHG) measurement shows some advantages over an EO sampling technique. We demonstrate a 3D electric-field visualization utilizing the EFISHG effect in nematic liquid crystals. The visualization was easily achieved with a second-harmonic-generation (SHG) confocal microscope with high spatial resolution on the order of or less than 1 /spl mu/m. With the great sectioning power in a confocal microscope, 3D images can be easily obtained combining different height images.

A 16-channel 200 GHz arrayed-waveguide grating (AWG) (de)-multiplexer is demonstrated experimentally by utilizing Si3N4 buried optical waveguides, which have 50 nm-thick Si3N4 cores and a 15 μm-thick SiO2 cladding. The structure with an ultra-thin core layer helps to reduce the scattering due to the sidewall roughness and consequently shows very low loss of about 0.4~0.8 dB/m. When using this type of optical waveguide for an AWG (de)multiplexer, there is no problem associated with gap refill using the upper-cladding material even when choosing a small (e.g., 1.0 μm) gap between adjacent arrayed waveguides, which helps to reduce the transition loss between the FPR (free-propagation region) and the arrayed waveguides. Therefore, the demonstrated AWG (de)multiplexer based on the present Si3N4 buried optical waveguides has a low on-chip loss. The fabricated AWG (de)multiplexer is characterized in two wavelength ranges around 1310 nm and 1550 nm, respectively. It shows that the crosstalk from adjacent and non-adjacent channels are about -30 dB, and -40 dB, respectively, at the wavelength range of 1310 nm. The Si3N4 AWG (de)multiplexer has a temperature dependence of about 0.011 nm/°C, which is close to that of a pure SiO2 AWG device.

We demonstrate planar Si3N4 ring resonators with ultra-high quality factors (Q) of 19 million, 28 million, and 7 million at 1060 nm, 1310 nm, and 1550 nm, respectively. By integrating the ultra-low-loss Si3N4 ring resonators with laterally offset planar waveguide directional couplers, optical add-drop and notch filters are demonstrated to have ultra-narrow bandwidths of 16 MHz, 38 MHz, and 300 MHz at 1060 nm, 1310 nm, and 1550 nm, respectively. These are the highest Qs reported for ring resonators with planar directional couplers, and ultra-narrowband microwave photonic filters can be realized based on these high-Q ring resonators.

not Available.

Heterogeneous integration of InGaAsP microdisk lasers on a silicon platform is demonstrated experimentally using an optofluidic assembly technique. The 200-nm-thick, 5- and 10-μm-diameter microdisk lasers are fabricated on InP and then released from the substrates. They are reassembled on a silicon platform using lateral-field optoelectronic tweezers (LOET). The assembled laser with 5-μm diameter exhibits a threshold pump power of 340 μW at room temperature under pulse condition. The heterogeneously-integrated InGaAsP-on-Si microdisk laser could provide the much needed optical source for CMOS-based silicon photonics. The small footprint and low power consumption make them attractive for optical interconnect applications. The optofluidic assembly technique enables efficient use of the III–V epitaxial materials in silicon photonic integrated circuits.

An electric-field-induced second-harmonic-generation signal in a nematic liquid crystal is used to map the electric field in an integrated-circuit-like sample. Since the electric-field-induced second-harmonic-generation signal intensity exhibits a strong dependence on the polarization of the incident laser beam, both the amplitude and the orientation of the electric field vectors can be measured. Combined with scanning second-harmonic-generation microscopy, three-dimensional electric field distribution can be easily visualized with high spatial resolution of the order of 1 microm.