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Ink-jet print attributes such as color gamut, grain, and cost are consequences of the materials and printing technology used and of choices made during color management, color separation, and halftoning operation. Traditionally, color separation determines what amounts of the available inks to use for each reproducible color, and halftoning deals with the spatial distribution of inks that also results in the nature of their overprinting. However, using an ink space as a means of communication between color separation and halftoning gives access only to some of the printed patterns that a printing system is capable of and, therefore, only to a reduced range of print attributes. Here, a method, i.e., Halftone Area Neugebauer Separation, is proposed to gain access to all possible printable patterns by specifying relative area coverages of a printing system's Neugebauer primaries instead of only ink amounts. This results in delivering prints with more optimal attributes (e.g., using less ink and giving rise to a larger color gamut) than is possible using current methods. [ABSTRACT FROM PUBLISHER]

A novel method of graded junction termination extension (JTE) formation for high-voltage 4H-SiC power devices is presented. Unlike conventional multiimplantation or tapered thickness mask approaches utilizing several photolithography steps, the new termination technique utilizes a single mask with window areas varied laterally away from the main junction, a single-step boron implantation, and drive-in diffusion at elevated temperature. Numerical device simulations have been performed for the initial JTE structure and mask optimization. 4H-SiC p-i-n rectifiers with an active area of 1 mm x 1 mm were fabricated and characterized. The fabricated devices exhibited 2.5-kV blocking voltage, which is close to the theoretical value of an ideal parallel-plane p-n junction. [ABSTRACT FROM AUTHOR]

A method using scatterometry for simultaneous focus and critical dimension (CD) control method has been developed. Our focus and CD measurement method uses a five-layer scatterometry model and provides stable focus measurement when the exposure dose fluctuates. We utilize this feature and consider applying it to the response surface methodology model for focus and CD control. This control optimizes focus and calculates the correct dose allowing for the focus effect. We have confirmed that this method controls photoresist shape accurately and reduces the CD variation for 65 nm devices by 80%. [ABSTRACT FROM AUTHOR]

Compliant free-standing structures can be used as chip-to-substrate interconnects. Such "compliant interconnects" are a potential solution to the requirements that will be imposed on chip-to-substrate interconnects over the next decade. However, cost of implementation and electrical performance limit compliant interconnects. In our previous work, we have proposed a new compliant interconnect technology called FlexConnect to address these concerns with compliant interconnects. An innovative cost-effective MEMS-based fabrication process is used to fabricate these compliant interconnects. Sequential lithography and electroplating processes with up to two masking steps are utilized. Utilizing the proposed fabrication process, in this paper, FlexConnects are realized at a 100-μm pitch. High-frequency modeling of the electrical parasitics of the interconnect is performed. Through finite-element-based models, the advantage of using multiple electrical paths as part of the interconnect design is shown from a thermomechanical reliability perspective. Finally, taking advantage of the MEMS-based photolithographic fabrication process, a heterogeneous combination of FlexConnects and column interconnects is proposed. This approach is shown to be an additional avenue to attain improved electrical performance without compromising mechanical performance. [ABSTRACT FROM AUTHOR]

Photolithographically-defined patterned arrays of Co-rich Co-Pt permanent magnets with thicknesses up to 10 µm were fabricated by aqueous electrodeposition. These micromagnets exhibited strong perpendicular magnetic performance while being deposited at low temperatures (65° C) and without the need for post-deposition annealing. Co-Pt magnet arrays grown 10-µm thick on textured Cu (111) seed layers on Si (110) substrates exhibited coercivities of 330 kA/m (4.1 kOe) and energy products 69 kJ/m³. Additionally, magnets deposited 8-µm thick on untextured Cu seed layers on standard Si (100) substrates exhibited coercivities up to 260 kA/m (3.3 kOe) and energy products up to 27 kJ/m³. The high magnetic performance and process integrability of these permanent magnet arrays make them well suited for the development of magnetic microelectromechanical systems (MEMS). [ABSTRACT FROM AUTHOR]

In this paper, a proof of concept 4 x 4 active-matrix imager fabricated at near room temperature (<95 °C) is presented. Conventional photolithography and inkjet printing were used to pattern integrated organic FETs and photoconductors. The design and characterization of a pixel circuit is described. A simple first-order calibration technique is used to partially compensate for fixed pattern noise. Following the calibration, the imager is shown to correctly image a "T" pattern. [ABSTRACT FROM AUTHOR]

The photomechanicai properties of carbon nanotubes (CNTs) enable the construction of CNT-based optical actuators. Employing a microelectromechanical systems-compatible nanotube-patterning process by plasma etching, CNT ensembles are integrated into microsystems to realize microoptomechanical systems (MOMS) (CNT-MOMS), where nanotubes behave as both the structural materials and the actuation mechanism. In this paper, following the CNT-MOMS principle, we report on all-optical micromirrors from the CNTs. Photomechanical actuation of single-wall CNTs from polymer-/nanotube-film bimorph structures is designed to actuate the micromirrors. A large mirror angular displacement of 19° is obtained under laser illumination. Bidirectional rotation of the micromirrors is realized by the incorporation of two symmetrical serpentine bimorph actuators with the mirror surface. Furthermore, to add controllability to the micromirror rotations, absorptive-type optical filters are combined with the mirror structure in a "suspended" filter assembly. With green and red optical filters incorporated in the micromirrors, they show rotational selectivities of 10 : 1 and 20 : 1 for the 532- and 658-nm lasers, respectively. Depending on the wavelength of the incoming light, it could be selectively modulated into opposite directions by the micromirror. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the laser-induced ablation of bovine bone assisted by a transparent liquid layer on top of the target surface. A Q-switched Nd:YAG laser was used to ablate bovine tibia at various energy levels. Distilled water was applied to the sample surface in order to examine the role of a transparent liquid layer during the ablation. Plasma generation and transient acoustic waves were monitored to identify dominant mechanisms involved in the ablation process. Ablation efficiency was measured from the cross-sectional tomography acquired by optical coherence tomography (OCT). Ablation with a liquid layer lowered the damage threshold and enhanced both the laser-induced acoustic excitation and the ablation efficiency, which saturated at higher radiant exposures. The enhanced ablation of the liquid-assisted process is primarily due to photomechanical effects associated with explosive vaporization and plasma confinement. The saturation of the pressure amplitude and ablation efficiency was attributed to increased plasma shielding. [ABSTRACT FROM AUTHOR]

In order to improve productivity in the photolithography process of high-product mix/low-volume factories, an automated stepper load balance allocation system was developed. The system enables us to maintain a balanced load distribution of tool constraint layers among all steppers. We developed a processing time estimation function and a load balance allocation function. The processing time estimation function calculates accurate loads based on the processing times related to the product, the process layer, and the stepper. The load balance allocation function was realized by applying a dynamic programming method. The system has decreased the deviation in the total processing time among all steppers by 10%, compared to the conventional manual allocation method. [ABSTRACT FROM AUTHOR]

The measured performance of a column-type microthermoelectric cooler, fabricated using vapor-deposited thermoelectric films and patterned using photolithography processes, is reported. The columns, made of p-type Sb2Te3 and n-type Bi2Te3 with an average thickness of 4.5 pm, are connected Using Cr/Au/Ti/Pt layers at the hot junctions, and Cr/Au layers at the cold junctions. The measured Seebeck coefficient and electrical resistivity of the thermoelectric films, which were deposited with a substrate temperature of 130 °C, are -74 μV/K and 3.6 × 10-5 - m (n-type, power factor of 0.15 mW/K² - m), and 97 μV/K and 3.1 × 1o-5 Ω - m (p-type, power factor of 0.30 mW/K² - m). The cooling performance of devices with 60 thermoelectric pairs and a column width of 40 μm is evaluated under a minimal cooling load (thermobuoyant surface convection and surface radiation). The average cooling achieved is about 1 K. Fabrication challenges include the reduction of the column width, implementation of higher substrate temperatures for optimum thermoelectric properties, and improvements of the top connector patterning and deposition. [ABSTRACT FROM AUTHOR]

This paper delineates a comprehensive and successful application of decision tree induction, to 1054 records of production lots taken from a lithographic process with 45 processing steps. Complex interaction effects among manufacturing equipment that lead to increased product variability have been detected. The extracted information has been confirmed by the process engineers, and used to improve the lithographic process. The paper suggests that decision tree induction may be particularly useful when data is multidimensional, and the various process parameters and machinery exhibit highly complex interactions. Another implication is that on-line monitoring of the manufacturing process (e.g., closed-loop critical dimensions control) using data mining may be highly effective. [ABSTRACT FROM AUTHOR]

Integrating the photosensitive and memory properties into one single device, organic phototransistor memory (OPTM) is promising for applications in optoelectrical fields. By optimizing the channel length/width ratio and the resistance of the electrode lead, OPTM performance could be improved effectively. Interestingly, the OPTM showed no obvious memory effect with an electrical programming process, while applied along with light illumination, the photoresponsivity, photocurrent/dark current ratio, and shift of threshold voltage could achieve the highest values, which were 3.59 A W \(^{-1}\) , \(1.4~\times ~10^{4}\) , and 14.4 V, respectively. Notably, the retention time over \(1.8~\times ~10^{5}\) s was 27 times longer than our previous reports and could ensure the application in nonvolatile memories. Furthermore, the OPTM could be applied in programmable and erasable circuit. It is also potential in flexible device. [ABSTRACT FROM AUTHOR]

Conventional halftoning methods employed in electrophotographic printers tend to produce Moire artifacts when used for printing images scanned from printed material, such as books and magazines. We present a novel approach for descreening color scanned documents aimed at providing an efficient solution to the Moire problem in practical imaging devices, including copiers and multifunction printers. The algorithm works by combining two nonlinear image-processing techniques, resolution synthesis-based denoising (RSD), and modified smallest univalue segment assimilating nucleus (SUSAN) filtering. The RSD predictor is based on a stochastic image model whose parameters are optimized beforehand in a separate training procedure. Using the optimized parameters, RSD classifies the local window around the current pixel in the scanned image and applies filters optimized for the selected classes. The output of the RSD predictor is treated as a first-order estimate to the descreened image. The modified SUSAN filter uses the output of RSD for performing an edge-preserving smoothing on the raw scanned data and produces the final output of the descreening algorithm. Our method does not require any knowledge of the screening method, such as the screen frequency or dither matrix coefficients, that produced the printed original. The proposed scheme not only suppresses the Moire artifacts, but, in addition, can be trained with intrinsic sharpening for deblurring scanned documents. Finally, once optimized for a periodic clustered-dot halftoning method, the same algorithm can be used to inverse halftone scanned images containing stochastic error diffusion halftone noise. [ABSTRACT FROM AUTHOR]