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This study addresses the characteristics of polycrystalline-silicon thin-film transistors (poly-Si TFTs) with 3-D finlike channels fabricated using ultraviolet nanoimprint lithography. The poly-Si 3-D finlike channels with a line width/space ratio of about $\sim$ 1 : 1 were fabricated and studied by scanning electron microscope and transmission electron microscopy. The poly-Si TFTs with 3-D finlike channels, fabricated using the nanoimprint technique, have superior performances in comparison to that with the single channel. Besides, the characteristics of poly-Si TFTs, such as the transfer characteristics, output drain current, transconductance, on/off current ratio, subthreshold swing, and field-effective mobility, with respect to the width/space/height of 3-D finlike structures were also investigated. The proposed approach can be utilized to fabricated high-performance poly-Si TFTs or high-sensitivity biosensors at low cost.

In recent years, global economic environmental are facing a fluctuated and unstable period. Due to the influence of subprime mortage crisis in USA and debt crisis in Europe, bankdruptcy of many large enterprises occurs one after another. In many countries, credit bankruptcy and violation of debt contract also occurs frequently, the violation of settlement in stock market can even be seen occasionally. This indicates that for many companies, not only risk is not well managed, but also the risk they are facing with is not well understood. To avoid possible business operation risk, the managers of a company really need to inspect the financial situation and characteristic of a company in advance. In this study, first, profitability force and growth force of financial five forces are used to the financial ratio data collected from the enterprises of China. Meanwhile, stability force and activity force is used to perform Grey Relational Analysis and the analysis results are sorted according to grey relational ...

Taiwan stock market trend is fast changing. It is affected by not only the individual investors and the three major institutional investors, but also impacted by domestic political and economic situations. Therefore, to precisely grasp the stock market movement, one must build a perfect stock forecast model. In this article, we used a multi-stage optimized stock forecast model to grasp the changing trend of the stock market. First, data of 2 stocks, TSMC and UMC were collected, and then inputted the test data into the genetic programing and built a model to find out the arithmetic expressions. Artificial Fish Swarm Algorithm is used to dynamically adjust the variable factors and constant factors in the arithmetic expressions. Next, we took the error term (e) in arithmetic expressions to Gray Model Neural Network to make the forecast. Finally, we used the Artificial Fish Swarm Algorithm to dynamically adjust the parameters of the Gray Model Neural Network to enhance the precision of the stock forecast model as a whole. The result showed that the forecast capability of each stage after the optimization process is better than that of its previous stage, and the mixed stock forecast model (GP–AFSA+GMNN–AFSA) in stage 4 greatly enhanced the precision of the forecast.

In this paper, we propose a power-efficient configurable multiple-input-multiple-output (MIMO) detector, supporting QPSK, 16-QAM, and 64-QAM with low complexity. The approach divides a large MIMO detector into two subsystems: a core detector and a residual detector. The core detector, a low-cost 2 times 2 V-BLAST with ML detector, is used to detect the first two significant outputs. This detector not only efficiently increases the reliability of the entire MIMO detector through its ML performance in mitigating error propagation but also reduces the computational complexity by its search space reduction capability to decrease the computation from O(C 2

For advanced lithography metrology, SCD (Scatterometry Critical Dimension) is a common metrology technique applied to control processes. SCD has the capability to report accurate data information such as CD (Critical Dimensions), photoresist SWA (Side Wall Angle) and photoresist HT (Height). The shape of photoresist correlates with inline process controllers, namely scanner focus and dose. However, SCD is a model-based metrology method. In order to decode the process controllers, it requires computation from a geometric model. Once the model extracts the resist shape information from the spectra, one needs further correlation of those geometric parameters with the process controllers for monitoring. Thus, information loss through multiple modeling is a major concern. Indeed, during data transformation, noise and model approximation can distort the signals, in other words, the critical parameters, focus and dose, may not be measured accurately. This study therefore seeks a methodology to monitor focus and dose with the least amount of information transformation. Signal Response Metrology is a new measurement technique that obviates the need for geometric modeling by directly correlating focus, dose or CD to the spectral response of a SCD-based metrology tool.

Tubulopapillary hidradenoma (TPH)1 is a term proposed to describe morphological dermal ductal tumors with both eccrine and apocrine differentiation. The term TPH encompasses a spectrum of lesions that includes tubular apocrine adenoma (TAA) and papillary eccrine adenoma (PEA):2 PEA and TAA can be indistinguishable both clinically and histologically. We described a case of TPH with both prominent eccrine and apocrine differentiation combined with syringocystadenoma papilliferum (SCAP) over the distal extremity. This rarely encountered dermatopathological phenomenon is the sixth reported case from the literature in which PEA or TAA and SCAP were present in the same lesion.3–7 Furthermore, the tumor had a warty surface, which is histologically consistent with a typical viral verruca. Although PCR and DNA probe hybridization for human papilloma virus (HPV) types 2, 6/11, 16 and 18 failed to reveal positive results, the location and clinicopathologic correlation convinced us that superimposed HPV could not be excluded.

This letter addresses the characteristics of polycrystalline-silicon (poly-Si) thin-film transistor (TFTs) with 3-D finlike channels fabricated using UV nanoimprint lithography. A transparent mold and poly-Si 3-D finlike channels with a line/space ratio of about 1:1 were fabricated and studied by SEM. The poly-Si TFTs with 3-D finlike channels, fabricated using a nanoimprint technique, have lower threshold voltage, higher ON/OFF current ratio, better subthreshold swing, higher field-effective mobility, and higher drain current than that with a single channel. The proposed approach can be utilized to fabricate high-performance poly-Si TFTs at low cost.

In advanced semiconductor N14 processes, due to the requirement of shrinking pitches for increased densities, pattern split is introduced. However, each of the two pattern split methods, SADP (Self-Aligned Double Patterning) and LELE (Litho-Etch-Litho-Etch), can incur process variations that might cause “pitch walk” [1, 3]. Pitch walk is a by-product of line critical dimension (CD) and spacer error (in SADP) or overlay variations (in LELE). Pitch walk not only results in different line and spaces but also affect the later steps, for example, different etched depths due to loading effects. Because of those behaviors, it is therefore a requirement to control the CD for better uniformity. This paper demonstrates how to use SCD (Scatterometry Critical Dimension) metrology tools to measure the different critical dimensions and spaces to control CD and overlay at the same process step [2]. Traditionally, wafers have to go through both a CD metrology tool and an overlay tool in order to verify CD uniformity and grid uniformity. The methodology introduced in this paper can efficiently shorten cycle time since only the CD metrology tool will be used to verify both CD and overlay. SpectraShape™ is a proven optical CD platform based on spectroscopic ellipsometry and reflectometry. In optical model type metrology, pitch walk can be a challenging parameter to measure due to inherent low sensitivity. Hence this study is performed on the newest generation system, the SpectraShape™ 9010. A new, laser driven light source [4] on this SCD tool provides higher light intensity, producing better signal-to-noise ratios for critical device parameters. This paper explores the use of SCD to measure both resist and hard mask CD in a single step. In addition, results will be presented on using SCD to measure pitch walk, typically a low sensitivity parameter for optical CD metrology tools.

In this paper, we propose a novel augmenting and partitioning scheme for constructing multistage interconnection networks (MINs) with improved fault-tolerant capabilities. We first propose a partitioning scheme to construct and analyze partitioned MINs (PMINs). A simulation method is developed, based on the stuck-at fault model, to evaluate dynamic full access (DFA) and average number of passes in PMINs. We then propose an augmenting scheme to construct augmented partitioned MINs (APMINs) with further enhanced fault-tolerant capabilities. Simulation analysis of APMINs, based on the switch level fault model, showed that the proposed scheme significantly improves the fault-tolerant capability of MINs. Finally, the effectiveness of the proposed scheme is evaluated with respect to cost, DFA, locality, and average path length.

In previous work, a novel scheme for constructing fault-tolerant multistage interconnection networks (MINs) was presented. The constructed augmented partitioned MINs (APMINs) were evaluated using a switch level fault model in terms of full access (FA) and dynamic full access (DFA) measures. The simulation results showed that the proposed scheme significantly improved the fault-tolerant capability of MINs. Based on the small synchronous clock scheme, we first analyze the performance of this class of synchronous packet-switched APMINs. We then evaluate the performance of the APMIN-based tightly coupled and loosely coupled multiprocessor systems using a hybrid probabilistic and queueing model. The performance of this class of fault-tolerant multiprocessor systems and that of systems employing Omega and modified Omega (MD-Omega) networks are also compared.

From the innovative diffusion theory, it is known that the early adopters have the characteristic of being liable to accept new products and generate new value from using new products. Through their social networks, they also transmit information about new products to the early majority. Moreover, from the use and gratification theory, if a new product provides users with usability of information, social value or entertainment, it is likely that this new product will be accepted because users' physical/mental need is fulfilled. Based on the above two principles, this study thereby develop a Human-Computing Grounded System. Expert first divides data as technical specification or value induced by early adopters, grounded theory analysis is then performed interactively. Results in this study indicate the new value induced by early adopters using new products which supported by new technology embedded in the new product. Meanwhile, inferred from the use and gratification theory, it is easier for the majority to accept a new product if this product offers more new values. By integrating multi-type of values conceived by the early adopters, our research model shows that indeed products with more and new values attract more majority.

The tight overlay budgets required for 45nm and beyond makes overlay control a very important topic. High order overlay control (HOC) is becoming an essential methodology to remove the immersion induced overlay signatures. However, to implement the high order control into dynamic APC system requires FA infrastructure modification and a stable mass production environment. How to achieve the overlay requirement before the APC-HOC system becomes available is important for RD environment and for product early ramp up phase. In this paper authors would like to demonstrate a field-by-field correction (FxFc) or correction per exposure (CPE) methodology to improve high order overlay signature without changing current APC-linear control system.

Information technology such as data mining or text mining, can extract useful data structure from data. But extracted data structure was hardly used in explaining the meaning of data itself. In reality, a laborer can hardly catch any meaningful job information from members of his work group (strong tie) when it comes to changing jobs. However, some of his friends (weak tie), although not so close to him, associated to other work groups, can bring him information about new jobs. This information is very important in job hunting. This kind of personal central base social networks can be used to realize a person's motivation and enrich his social capital, extends his resources to the resources of his linked friends. This process is called social chance discovery. Base on this concept, in this study, we build model of Qualitative Chance Discovery and apply it on DVD news. Experiment results show this model can be used as an interactive tool to help company understands the way of breaking entry barrier to compete with existing companies in the harsh environment of DVD industry.

This paper presents an efficient and practicable MIMO transceiver in which transmitter antenna selection is applied to minimum mean-squared-error V-BLAST (MMSE V-BLAST) detector and GMD precoding through limited feedback channel. The method compensates the deficiency of the GMD algorithm under ill-conditioned channel and improves the BER performance further. For over 4 × 5 antenna selection, the proposed antenna selection scheme can save more than 50% computational complexity compared with that of the exhausting method. Moreover, efficient precoder quantization and reconstruction are also analyzed and evaluated with satisfactory performance. From the simulation results, the proposed transceiver can achieve over 6 dB SNR improvement over the open-loop V-BLAST counterparts at BER=10−2 under i.i.d. channel.

The tight overlay budgets required for 45nm and beyond make overlay control a very important topic. With the adoption of immersion lithography, the incremental complexity brings much more difficulty to analyzing the source of variation and optimizing the sampling strategy. In this paper, there will be a discussion about how the use of an advanced sampling methodology and strategy can help to overcome this overlay control problem and insure sufficient overlay information to be captured for effective production lot excursion detection as well as rework decision making. There will also be a demonstration of the different correction methodologies to improve overlay control for dual-stage systems in order to maximize the productivity benef its with minimal impact to overlay performance.

As advanced semiconductor companies move forward to the 45nm technology node, traditional overlay sampling and linear correction used in dry lithography become less feasible to bring overlay control into the desired budget. New overlay control methodologies need to be established to meet the needs of much tighter overlay budgets in the immersion lithography process. Overlay source of variance (SOV) was first investigated to understand the major contributor of overlay error sources. The SOVis broken down into wafer, field, and random components in order to utilize the SOV information to prioritize overlay improvement decisions. High order wafer level or field level error components are commonly observed as a significant contributor and requires attention to bring the overlay residual into the desired limit. Optimal sample is determined in considering sample plan robustness and throughput impact while increasing sampling becomes a necessity in 45nm technology node.

Layer to layer alignment in optical lithography is controlled by feedback of scanner correctibles provided by analysis of in-line overlay metrology data from product wafers. There is mounting evidence that the "high order" field dependence, i.e. the components which contribute to residuals in a linear model of the overlay across the scanner field will likely need to be measured in production scenarios at the 45 and 32 nm half pitch nodes. This is in particular true in immersion lithography where thermal issues are likely to impact intrafield overlay and double pitch patterning scenarios where the high order reticle feature placement error contribution to the in-die overlay is doubled. Production monitoring of in-field overlay must be achieved without compromise of metrology performance in order to enable sample plans with viable cost of ownership models. In this publication we will show new results of in-die metrology, which indicate that metrology performance comparable with standard scribeline metrology required for the 45 nm node is achievable with significantly reduced target size. Results from dry versus immersion on poly to active 45 nm design rule immersion lithography process layers indicate that a significant reduction in model residuals can be achieved when HO intrafield overlay models are enabled.

Instructional outcome is an important part of instructional design theory which is hard to evaluate during education setting, especially, for attitude learning outcome. Traditionally, the most famous research method in attitude learning outcome is interview with open questionnaire. The drawback of interview method is the number of subjects is quite limited. This drawback can be improved by using new technology of text mining. Objective of this research is to find if there is any difference in cognitive learning for students from different backgrounds using text mining technology. The research is performed in three phases. First, documents of fifty four students concerning their thoughts after watching the film "Moon Child" were collected. High frequency terms were sifted from all terms to form the main thoughts of each and all documents. In the second phase, chaos theory was applied to divide these thoughts into two levels, basic concept level and attribute level. The main thoughts and each level of the main thoughts were visualized in network form and regarded as cognitive concept map. Finally, Average Path Length of cognitive concept maps were computed and analyzed. Experiment results indicate for students from different background, there is significant difference in their cognitive learning outcome. This result should be valuable for instructional design theory and can be served as an alternative in evaluating instructional outcome in the near future.

In this paper, a baseband processor including whole transceiver system for WCDMA/HSDPA communications is presented. In order to resist the non-ideal effect of the wireless channel, the receiver of the proposed processor consists of a channel estimator for channel estimation and receiver parameters calculation, a carrier frequency synchronization and timing synchronization block for carrier frequency offset and clock offset compensation, moreover, an adaptive equalizer for ISI suppression. In receiver architecture design, we adopt applicable algorithms to design each building blocks, so as to minimize the area complexity and power consumption but still with good performance. After system architecture design and system performance simulation, we do some rough evaluation from system architecture about the area and power consumption of the proposed processor.

In this paper, a baseband transceiver system, architecture design and verification for WCDMA/HSDPA communications is presented. The proposed receiver consists of a channel estimator for channel estimation and receiver parameter calculation, a carrier synchronization and timing synchronization block for carrier frequency offset and clock offset compensation, and an equalizer for ISI suppression. The receiver architecture design adopts applicable algorithms to design each building blocks but still with good performance or even better. The final simulation results show the proposed architecture can satisfy the system specification with better performance compared to other implementations.

The integrated circuit (IC) manufacturing factories have measured overlay with conventional "box-in-box" (BiB) or "frame-in-frame" (FiF) structures for many years. Since UMC played as a roll of world class IC foundry service provider, tighter and tighter alignment accuracy specs need to be achieved from generation to generation to meet any kind of customers' requirement, especially according to International Technology Roadmap for Semiconductors (ITRS) 2003 METROLOGY section1. The process noises resulting from dishing, overlay mark damaging by chemical mechanism polishing (CMP), and the variation of film thickness during deposition are factors which can be very problematic in mark alignment. For example, the conventional "box-in-box" overlay marks could be damaged easily by CMP, because the less local pattern density and wide feature width of the box induce either dishing or asymmetric damages for the measurement targets, which will make the overlay measurement varied and difficult. After Advanced Imaging Metrology (AIM) overlay targets was introduced by KLA-Tencor, studies in the past shown AIM was more robust in overlay metrology than conventional FiF or BiB targets. In this study, the applications of AIM overlay marks under different process conditions will be discussed and compared with the conventional overlay targets. To evaluate the overlay mark performance against process variation on 65nm technology node in 300-mm wafer, three critical layers were chosen in this study. These three layers were Poly, Contact, and Cu-Metal. The overlay targets used for performance comparison were BiB and Non-Segmented AIM (NS AIM) marks. We compared the overlay mark performance on two main areas. The first one was total measurement uncertainty (TMU)3 related items that include Tool Induced Shift (TIS) variability, precision, and matching. The other area is the target robustness against process variations. Based on the present study AIM mark demonstrated an equal or better performance in the TMU related items under our process conditions. However, when non-optimized tungsten CMP was introduced in the tungsten contact process, due to the dense grating line structure design, we found that AIM mark was much more robust than BiB overlay target.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A 15-year-old, unmarried female presented to our dermatology department for an intensely pruritic skin rash that had appeared abruptly 3 days earlier. She had a remarkable medical history for a case of allergic rhinitis and several attacks of asthma in her early childhood. The condition waxed and waned initially but had improved in recent years. Physical examination revealed several erythematous plaques, papules studded with scattered pustules having diameters less than 0.3 mm. Conspicuous scratch marks had caused erythematous wheal-like indurations also studded with pustules in a linear distribution across the waist, forearms (Fig. 1), and back (Fig. 2). Discrete papulopustules were present on the face, nape and neck. The patient was otherwise healthy. There were no other symptoms such as fever, malaise, weakness, or lymphadenopathy Laboratory results were normal for hepatic and renal functions, serum electrolytes, glucose, protein, erythrocyte sedimentation rate (8 mm/h), and C-reactive protein (0.355 mg/l). A human immunodeficiency virus (HIV) antibody screen test was negative. Serum was positive for herpes simplex virus (HSV)-1 and HSV-2 IgG (in low titers), but negative for HSV-1 and HSV-2 IgM. White blood cell count revealed leukocytosis (11.2 x 10(3)/l), with a differential count of 68% neutrophils, 27% lymphocytes, and 8% eosinophils. Serum IgA, IgG, and IgM were within normal limits, but the IgE level was elevated (677 mg/dl). Cultures from peripheral blood and pustules were negative. A Tzank smear performed on the pustules showed no multinucleated giant cells. Fungal testing of skin scrapings from the initial lesion site gave negative results. Routine stool tests, including common pathogen and parasite screens, were negative, and urinalysis results were unremarkable. A biopsy specimen obtained from a skin pustule showed subcorneal eosinophilic and neutrophilic pustules in the follicular infundibulum with marked spongiosis of the follicular epithelium. (Fig. 3). There was a moderately dense superficial and deep perivascular mixed inflammatory cell infiltrate comprising eosinophils, neutrophils and lymphocytes. Migration of eosinophils and neutrophils through the vessel wall with variable luminal intramural fibrin deposition, histologically indicative of vasculopathy, was seen. There was concomitant slight perivascular dermal necrosis. (Fig. 4). Based on the clinical presentation and light microscopic findings on biopsy, a diagnosis of eosinophilic pustular folliculitis with pathergy was made. Systemic prednisolone 30 mg in divided doses was given. After 1 week of systemic corticosteroid therapy, the patient's condition was significantly improved and the patient was subsequently discharged. Two months later she had a relapse, upon which corticosteroid therapy was commenced leading to lesional resolution. The foci of eosinophilic folliculitis healed with areas of hyperpigmentation with variable scarring.

Tubulopapillary hidradenoma (TPH)1 is a term proposed to describe morphological dermal ductal tumors with both eccrine and apocrine differentiation. The term TPH encompasses a spectrum of lesions that includes tubular apocrine adenoma (TAA) and papillary eccrine adenoma (PEA):2 PEA and TAA can be indistinguishable both clinically and histologically. We described a case of TPH with both prominent eccrine and apocrine differentiation combined with syringocystadenoma papilliferum (SCAP) over the distal extremity. This rarely encountered dermatopathological phenomenon is the sixth reported case from the literature in which PEA or TAA and SCAP were present in the same lesion.3-7 Furthermore, the tumor had a warty surface, which is histologically consistent with a typical viral verruca. Although PCR and DNA probe hybridization for human papilloma virus (HPV) types 2, 6/11, 16 and 18 failed to reveal positive results, the location and clinicopathologic correlation convinced us that superimposed HPV could not be excluded.

Ion implantation is a key process for front end of line semiconductor manufacturing and directly correlates to device performance. Inability to rework mandates precise control. As of today, there is still limited production worthy solution for in-line boron implanted energy and dose monitor on product wafer. This paper describes a fast and accurate in-line method for monitoring Boron (B) implantation energy and dose measurement, simultaneously, in a production environment using spectroscopic ellipsometry (SE) after the source-drain PMOS implant process step. The implanted species damage the silicon substrate lattice, producing amorphous-Si like characteristics and a different refractive and absorption indexes compared to crystalline silicon substrate. Furthermore, the damaged depth is a function of implant energy. SE spectra are very sensitive to measure the optical properties variation of these materials (Figure 1). In this work, a single look-up optical model is created to monitor the damaged layer. The look-up components relate to implanted dose behavior, the thickness of the damage layer to the implanted depth (energy) behavior. Secondary Ion Mass Spectrometer (SIMS) is used as a reference tool. Excellent correlation (R2> 0.99) can be achieved between SE results and SIMS (Figure 2). The damaged layer thickness correlates to SIMS depth (Rp); and the look-up model components correlate to SIMS dose. Q-time limitation must be considered to achieve stable implantation monitoring before annealing. The implanted surface is unstable and damaged depth and implanted dose decay rapidly within a few hours. Q-time correlation formula is used to compensate the implanted decay behavior (Figure 3). As a result, 1.64% depth and 0.43% dose range variation can be achieved after Q-time correlation is applied. This research also shows that SE metrology is sensitive to other species used for source-drain implantation and can be extended to control NMOS implant process using Arsenic (As) species.

This work addresses the characteristics of a nonvolatile polycrystalline-silicon thin-film-transistor silicon–oxide–nitride–oxide–silicon (SONOS) memory with periodical finlike channels fabricated using nanoimprint lithography. The polycrystalline silicon periodical finlike channels were fabricated using ultraviolet (UV) nano-imprint lithography and studied by transmission electron microscopy (TEM). The memories with periodical finlike channels have lower operation voltage, higher programming speed, larger memory window, and better endurance and data retention than those with a single channel. The proposed approach can be utilized to fabricate a high-performance thin-film-transistor memory at a low cost.