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Indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) with a 1 um channel length were successfully fabricated by i-line lithography with a stepper process, resulting in high throughput. The a-IGZO TFT with a channel length of 1 μm exhibits high mobility of 8.77 cm2/Vs with an on/off current ratio of >3 × 1010. The stepper lithography process is capable of defect-free patterning given its precise layer-to-layer alignment and high image resolutions of the types required for large-area high-PPI displays. Consequently, IGZO TFTs can be fabricated on an 8-inch wafer with only minor electrical property deviations in the turn-on voltage, mobility, and on/off ratio. These results indicate that i-line lithography with a stepper process is a promising process for use in cutting-edge large-area electronics industries.

Indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) with a 1 um channel length were successfully fabricated by i-line lithography with a stepper process, resulting in high throughput. The a-IGZO TFT with a channel length of 1 μm exhibits high mobility of 8.77 cm2/Vs with an on/off current ratio of >3 × 1010. The stepper lithography process is capable of defect-free patterning given its precise layer-to-layer alignment and high image resolutions of the types required for large-area high-PPI displays. Consequently, IGZO TFTs can be fabricated on an 8-inch wafer with only minor electrical property deviations in the turn-on voltage, mobility, and on/off ratio. These results indicate that i-line lithography with a stepper process is a promising process for use in cutting-edge large-area electronics industries. [ABSTRACT FROM AUTHOR]

Twisted and coiled polymer muscles (TCPM) are inexpensive, light weight and simple artificial muscles that are introduced recently. For implementation of this muscle as a linear controllable actuator, we need an open loop or closed loop control system. In this paper we proposed a new artificial stepper tensile actuator based on joule-heated TCPM (we name it "stepper TCPM") that will be used as a stepping straight actuator and can be control via an open loop control system. There are not any sensors in the proposed actuator, so the actuator can be used in an open loop control system for stepping linear movements. This stepper actuator consists of some serial TCPM string with some individual heater isolated wires that twisted around the fiber of each TCPM. The maximum displacement of each TCPM is double of the previous TCPM, therefore the full set or reset of current of these wires result full contraction of each TCPM and stepping displacement control of stepper TCPM. Our experiment shows that we can control step by step displacement of proposed actuator without any sensor or closed loop control system (similar to common stepper motor but in straight motion). Proposed actuator is applicable in low cost and low weight stepping movement mechanism. [ABSTRACT FROM AUTHOR]

3D pixel sensors aimed at the upgrades of the ATLAS and CMS experiments at the High Luminosity LHC have small pixel size and pretty dense layouts. In addition, modified 3D designs with small pixel size and trenched electrodes in place of columnar electrodes are being developed to optimize the pixel timing performance in view of the LHCb upgrade. The fabrication of these advanced 3D pixels is challenging from the lithographical point of view. This motivated the use of stepper lithography at Fondazione Bruno Kessler in place of a standard mask aligner. The small minimum feature size and high alignment accuracy of stepper allow a good definition of the sensor geometries also in the most critical layouts, so that a higher fabrication yield can be obtained. In this paper, we will present the main design and technological issues and discuss their impact on the electrical characteristics of 3D pixel sensors of different geometries.

This paper describes the design and performance of two new high-resolution interline charge-coupled device image sensors for use in industrial, machine vision, and aerial photography applications. These sensors feature 4.5- $\mu \text{m}$ pixels, 4 outputs, fast dump gate, horizontal lateral overflow drain, and vertical electronic shutter. The 43-Mp sensor has a 35-mm optical format and the 50-Mp sensor has a larger format with a 2.175:1 aspect ratio that matches many modern mobile phone displays. This paper discusses the challenges and solutions to manufacture such large sensors with superior image quality such as uniformity, read noise, dark current, smear, transfer gate blooming, lag, and so on. [ABSTRACT FROM AUTHOR]

The tension in the warp yarns is a critical variable in the weaving process. If the warp tension is too high or too low the weaving process will be interrupted. A parameter that directly affects the warp tension is the vertical warp stop motion position. The position of the warp stop motion must be set for every produced new article. The setting procedure is performed completely manual. In this paper we present a mechatronic modification of an air jet-weaving machine to adjust the vertical warp stop motion position with the help of actuators. The parameters for the automated movement are determined and an open loop control, which uses a PLC, is proposed.

Gender recognition is trivial for a physiotherapist, but it is considered a challenge for computers. The electromyography (EMG) and heart rate variability (HRV) were utilized in this work for gender recognition during exercise using a stepper. The relevant features were extracted and selected. The selected features were then fused to automatically predict gender recognition. However, the feature selection for gender classification became a challenge to ensure better accuracy. Thus, in this paper, a feature selection approach based on both the performance and the diversity between the two features from the rank-score characteristic (RSC) function in a combinatorial fusion approach (CFA) (Hsu et al.) was employed. Then, the features from the selected feature sets were fused using a CFA. The results were then compared with other fusion techniques such as naive bayes (NB), decision tree (J48), k-nearest neighbor (KNN) and support vector machine (SVM). Besides, the results were also compared with previous researches in gender recognition. The experimental results showed that the CFA was efficient and effective for feature selection. The fusion method was also able to improve the accuracy of the gender recognition rate. The CFA provides much better gender classification results which is 94.51% compared to Barani's work (90.34%), Nazarloo's work (92.50%), and other classifiers. [ABSTRACT FROM AUTHOR]

In this paper, we address the problem of lens aberration adjustment for lenses of semiconductor lithography equipment. The objective of aberration adjustment is to minimize the maximum value of aberration in any part of the images that are projected on the wafer. Formerly, an approximate solution method has been used, which is based on a brute force search for a subset of all cases. However, using that method, computational times are often long and a faster solution method is necessary. Nowadays, owing to significant progress in mathematical programming research, MIP (Mixed Integer Programming) solvers can reach an optimal solution quite fast. That is why, in this paper, we propose an exact solution method based on 0-1 MIP, which addresses the same “lens aberration” problem with the same objective of minimizing maximum absolute value of lens aberration. In real-world 9 instances, our solution method improves maximum aberration values by 18% to 56% over similar results from conventional solution methods.

In this paper, we consider the problem of lens distortion adjustment of semiconductor lithography equipment. The objective of adjustment is to minimize the maximum absolute value of distortion. Formerly, an approximate solution method based on the least-squares method has been used. Recently, an approximate solution method based on iterative least-squares method with weight was proposed. However, calculation of that method often takes long time and a better calculation method has been desired. In this paper, we propose an exact solution method based on LP (Linear Programming) to minimize the maximum absolute value of distortion. Now, LP solvers find an optimal solution very fast owing to the progress in linear programming research. Consequently, optimal solutions for 20 instances obtained by our method provided adjustment parameter settings about 29% from 27% better than that by the solution method based on the least-squares method.

Gender recognition is trivial for a physiotherapist, but it is considered a challenge for computers. The electromyography (EMG) and heart rate variability (HRV) were utilized in this work for gender recognition during exercise using a stepper. The relevant features were extracted and selected. The selected features were then fused to automatically predict gender recognition. However, the feature selection for gender classification became a challenge to ensure better accuracy. Thus, in this paper, a feature selection approach based on both the performance and the diversity between the two features from the rank-score characteristic (RSC) function in a combinatorial fusion approach (CFA) (Hsu et al.) was employed. Then, the features from the selected feature sets were fused using a CFA. The results were then compared with other fusion techniques such as naive bayes (NB), decision tree (J48), k-nearest neighbor (KNN) and support vector machine (SVM). Besides, the results were also compared with previous researches in gender recognition. The experimental results showed that the CFA was efficient and effective for feature selection. The fusion method was also able to improve the accuracy of the gender recognition rate. The CFA provides much better gender classification results which is 94.51% compared to Barani’s work (90.34%), Nazarloo’s work (92.50%), and other classifiers.

Background. Lumbar pain has a medical, psycho-emotional and social importance. At present, more acccent is placed on pain phytotherapy. Of plants, Symphytum officinale (SO) is known for its anti-inflammatory and analgesic actions. Aims. The objective of the study is to monitor the influence of moderate physical exertion on some sedentary subjects with subacute low back pain, after their treatment with a phytotherapic ointment containing SO (PSO), compared with non-treated control subjects. Methods. The chosen subjects (n=30) were selected based on the requirements of the study. Exercise consisted of pedaling on the Stepper 130 rpm/0-999 W/RUN 7414-15-T, 8 days, 3 min/test/day, at a strength that was increased by 11 watts/day. The analyzed indicators were local pain sensation (P) and anxiety (A). The chosen phytotherapy preparation was PSO. Statistical evaluation was done based on the Student test. Results. Following PSO administration, P decreased in the period prior to exercise, and P and A were significantly reduced during exercise, compared to the untreated group, at all testing times. Conclusions. 1) At the end of PSO ointment therapy, both after the first and the second period of phytotherapeutic preparation use, the sensation of pain was significantly reduced in subjects with subacute lumbar pain. 2) The pain sensation and anxiety were significantly reduced in subjects treated with PSO ointment compared with untreated subjects, under moderate physical exertion conditions by pedaling on a stepper. 3) OSP ointment phytotherapy provided antalgic and emotional protection in the treated subjects, in moderate exercise by stepper pedaling. 4) Given the results obtained with the PSO ointment, as well as its therapeutic qualities of good tolerance by the body, absence of toxicity and economic accessibility, we propose its use by subjects with subacute low back pain, as a form of pain therapy and antalgic protection, during rest and under moderate exercise conditions. [ABSTRACT FROM AUTHOR]

Abstract: Inertial stepping motors (ISMs) are widely used in high precision applications, such as scanning tunnelling microscopy and/or micro manipulation. The resolution they are able to reach makes them especially suitable when long stroke and high resolution are needed simultaneously. However, the limited speed of this technology is its main drawback. To overcome this drawback, the present paper proposes to use an amplified actuator in an ISM instead of a classical direct actuator. The impact of this choice is studied here, from speed and electrical current points of view. This study determined in an analytical way the influence of the actuator stroke on the step size of an ISM via an optimised control signal. The results are then confronted to a lumped model to identify potential limitations. Finally, a test bench is built using three different piezoelectric actuators to obtain experimental feedback about the benefits of actuator amplification in ISMs. [Copyright &y& Elsevier]

In this paper, hardware integration and control design for a dual-axis linear stepper (Sawyer) motor are addressed. In particular, the Sawyer motor used in the Yaskawa/MotoMan manufacturing system, which is utilized in various applications such as assembly, packaging, sorting, and probing, is considered. These motors are equipped with four optical sensors with a position resolution of 0.25 \mum. A detailed mathematical model of the motor is developed, and two control designs for position tracking, namely, a PD (or PID) controller and a robust adaptive nonlinear controller, are described along with experimental results. A number of practical issues (such as delay/latency, finite sampling time, sensor noise, commutation rate, and motor rotation) that must be addressed to achieve high performance are outlined and experimentally demonstrated. Both of the considered controllers utilize knowledge of motor position and velocity in all axes. Current measurements are not required. Either numerical differentiation or a dynamic observer can be used to construct the velocity signals from the measured position data. The designed robust adaptive nonlinear controller provides practical stabilization of position tracking errors and utilizes adaptations so that no knowledge of the electromechanical system parameters is required. The controller is robust to load forces and load torque (i.e., disturbance torque in yaw axis), friction, and cogging forces. Furthermore, the controller corrects for the unintended yaw and achieves synchrony of the motor and rotor teeth. [ABSTRACT FROM AUTHOR]

This paper presents a new type of pneumatic motor, a pneumatic step motor (PneuStep). Directional rotary motion of discrete displacement is achieved by sequentially pressurizing the three ports of the motor. Pulsed pressure waves are generated by a remote pneumatic distributor. The motor assembly includes a motor, gearhead, and incremental position encoder in a compact, central bore construction. A special electronic driver is used to control the new motor with electric stepper indexers and standard motion control cards. The motor accepts open-loop step operation as well as closed-loop control with position feedback from the enclosed sensor. A special control feature is implemented to adapt classic control algorithms to the new motor, and is experimentally validated. The speed performance of the motor degrades with the length of the pneumatic hoses between the distributor and motor. Experimental results are presented to reveal this behavior and set the expectation level. Nevertheless, the stepper achieves easily controllable precise motion unlike other pneumatic motors. The motor was designed to be compatible with magnetic resonance medical imaging equipment, for actuating an image-guided intervention robot, for medical applications. For this reason, the motors were entirely made of nonmagnetic and dielectric materials such as plastics, ceramics, and rubbers. Encoding was performed with fiber optics, so that the motors are electricity free, exclusively using pressure and light. PneuStep is readily applicable to other pneumatic or hydraulic precision-motion applications [ABSTRACT FROM PUBLISHER]

This research develops dispatching algorithms for a fab with machine-dedication characteristics. Machine-dedication, a new feature in a modern fab, has not been addressed in previous studies of dispatching. Three performance indices, including hit rate, mean cycle time, and throughput are of concern in dispatching. This research develops an algorithm, called LB-SA, based on a proposed simplification model of the process route. The line balance (LB) component aims to smooth the flow rate of the process route; and the starvation avoidance (SA) component aims to ensure that the bottleneck machine is not “starving” and has enough work-in-progress (WIP) to process all the time. Thirty dispatching algorithms, including the LB-SA algorithm, are compared by simulation. The LB-SA algorithm outperforms the other 29 algorithms both in terms of hit rate and mean cycle time, and is only slightly less than the best benchmark in throughput. Of the 29 other algorithms, one algorithm, called CR-SA, also performs very well. These two algorithms are both recommended for fabs with machine-dedication feature. [ABSTRACT FROM AUTHOR]

Abstract: Contact or proximity aligners or 1:1 projection aligners are conventionally used for patterning large-area devices like silicon strip detectors for high-energy particle detection. Reduction steppers offer a far better pattern fidelity and an increased productivity but a very limited field size. This paper describes methods to overcome the field size limitations to pattern large-area position-sensitive particle detectors automatically and accurately with a 5:1 reduction stepper. [Copyright &y& Elsevier]

In integrated circuit manufacture, owing to the limited optical system capability and the possibility of inaccurate mask installation in a stepper, image distortion of the mask pattern projected onto the wafer surface may occur during exposure. In this paper, the overlay distribution geometry was analysed to explore the physical properties of parameters in an overlay accuracy model for a stepper. The multiple linear regression method was also used to analyse overlay models to compare the error parameters obtained by different overlay models and the extent of possible improvements in overlay accuracy. If an appropriate overlay accuracy model can be established to reduce the systematic errors, overlay accuracy can be effectively improved. A multiple linear regression analysis of a simulation study was carried out. The elimination of the systematic error parameters was achieved by finding out the causes of these systematic errors in the overlay and eliminating them. This can reduce the standard deviation of the residual overlay to 19% of the original overlay and thus significantly improve the overlay. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a micromachined thermoelectric energy harvester with 6μm high thermocouples is fabricated by Stepper technology. Micromachined thermocouples are considered a cost-effective breakthrough solution for energy harvesters working at low thermal gradients and weak heat flows, typical for e.g. human body as well as machine-related waste heat. The thermoelectric generators will be used for autonomous wireless sensor nodes in a body area Network. [Copyright &y& Elsevier]