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PurposeIn recent years, student-managed investment funds (SMIFs), experiential learning programs at an increasing number of universities, have attracted significant scholarly interest. In this article, we review the academic literature on this pedagogy.Design/methodology/approachWe use the systematic review method to assess a sample of 85 articles published in 30 journals during the period 1975 to 2020.FindingsOur literature review reveals four streams of research: best practices and challenges, investment management, innovation and trends and SMIFs in a research setting. We also propose future research directions, including specific gaps in the literature, a focus on innovations to traditional programs, systematic investment performance and expansion into behavioral finance issues.Originality/valueWe contribute a comprehensive view of the body of scholarship on SMIFs, identifying existing streams of research and future research directions that will help guide the development of SMIF research into a cohesive and productive space.

Purpose The purpose of this paper is to expand the domain of experiential learning by sharing the experiences of establishing and developing student managed investment fund (SMIF) at West Virginia University (WVU). Design/methodology/approach This paper discusses the structure and performance of the SMIF at WVU within the context of experiential learning literature in financial education. Findings The adopted structure and coordination of SMIF appears to be effective in bridging the gap between classroom and the professional world, while significantly enhancing student experiential learning opportunities, engagement and professional preparedness. Originality/value The paper presents experience of launching and operating a SMIF at WVU, which has recently joined the ranks of R1 research universities. While the importance of research productivity has been on the rise, the significance of strengthening student experiences has also been growing and maintaining the balanced approach can be challenging. Enrollment in WVUs undergraduate finance program grew 33 percent over the past three years. With growing enrollment and competitiveness of finance degree programs, experiential learning opportunities like WVU’s SMIF are an essential for an evolving curriculum.

Purpose The purpose of this paper is to describe lessons learned from integrating student-managed investment funds (SMIFs) in finance education systems based on the case of the Raymond Rebsamen Investment Fund at the Sam M. Walton College of Business, University of Arkansas. Design/methodology/approach The paper has three main parts. First, it describes how the Rebsamen Fund operates as an integral part of undergraduate and graduate finance education at the Walton College. Second, it explains how the Fund spawned creation of sister funds, an institute, a 62-seat trading center, and coordinates with other agencies and stakeholders. Third, it lists strengths, weaknesses, opportunities and threats facing future SMIF integration into finance education. Findings The use of innovative experiential learning solutions like SMIFs bridging theory and practice can be enhanced by integrating them into effective systems of finance education. Practical implications Lessons learned include benefits of SMIF management by class, licensing and professional certification, trading centers, use of SMIF finances to support other components of education, proliferation of SMIFs, SMIF stimulation of academic units like centers/institutes, SMIF facilitation of collaboration, importance of tying SMIFs to student finance clubs, coordination of industry speaker visits between SMIF classes and clubs, and use of SMIFs in addressing cutting-edge challenges. Originality/value This paper discusses how SMIFs can be integrated in finance education.

Purpose For undergraduate-only, AACSB-accredited business programs, establishing a student managed investment fund (SMIF) can be an enormous, but potentially worthwhile, undertaking. Resources are often very limited – especially for faculty where their time is already consumed by teaching, administrative and publishing requirements. The purpose of this paper is to reflect on the five-year experience at Stonehill College and suggest considerations for undergraduate institutions seeking to establish such programs. Design/methodology/approach This is a retrospective on the experience of designing and implementing a SMIF-based academic program. Student education and professional skill development should be the primary outcomes evaluated with such programs. Included are brief perspectives on the program from its alumni with commentary on perceived value in one to four years following graduation. Findings The experience to date suggests that establishing a SMIF at a smaller, undergraduate-only institution is challenging. For a SMIF to generate educational returns commensurate with its cost, it needs to be part of a comprehensive, academic-driven program that garners broad support by the business faculty and administration of the college. Personal reflections by its program alumni suggest that it can be a very meaningful academic and experiential learning opportunity. Research limitations/implications This paper is focused largely on the experience of one institution. Further insights may be attained by a broader, unbiased analysis of institutions where SMIF programs have succeeded or failed to meet similar objectives. Practical implications The authors suggests that the creation of a SMIF program at smaller, undergraduate-only institutions faces unique challenges relative to larger, more well-endowed universities. These challenges can be overcome but not without a broad internal commitment. These programs, if done in a comprehensive way, can significantly impact student outcomes. Originality/value The retrospective offers up-to-date insights on the value and challenges of starting a SMIF program at smaller-sized, undergraduate-only academic institutions.

Purpose The purpose of this paper is to describe how a student-managed investment fund (SMIF) moved from an idea to an operational program over the period of a year at Memorial University in Newfoundland, Canada. The aim is to provide insight to other institutions on how to build capacity when developing their own SMIF. Design/methodology/approach I summarize the choices made with respect to funding source, governance structure, faculty involvement, recruitment, investment activities and integration into curriculum. Findings Underlying these choices were challenges pertaining to capacity, student competencies, the existing finance program and ties to industry. Through the development of the SMIF, efforts ensured that capacity was suitably developed in each of these areas. Research limitations/implications This paper provides insight to other institutions on how to build capacity while developing their own SMIF. Practical implications This account provides the field with a unique perspective. It is written following a year spent developing a SMIF that is about to launch. Originality/value This account provides the field with a unique perspective. It is written by a new faculty member following a year spent developing a SMIF that is about to launch.

Purpose The student-managed investment fund (SMIF) program at California State University, Long Beach (CSULB), was launched in 1995 with one portfolio worth $50,000. In the two decades since then, the program has grown to include three portfolios with a combined value of more than $700,000, managed on behalf of three different clients. The purpose of this paper is to describe the creation, evolution and growth of the program including the development of the new quantitative approach and its subsequent implementation. The paper also discusses the ongoing organizational, educational and investment-management challenges associated with the program. Design/methodology/approach The paper includes a description of the development and evolution of the program along with a discussion of the investment results for one of its three portfolios. Findings The paper finds: the new quantitative approach implemented in the program is effective as insurance against “black swan” events; and SMIF-type programs can provide learning experiences both for students and faculty members. Practical implications The paper explains the practical application of the new quantitative approach as well as the educational benefits of a SMIF-type program. Originality/value The paper provides insight into the structure of CSULB’s SMIF program and discusses a unique quantitative approach to asset allocation and security selection.

Purpose The purpose of this paper is to provide a detailed framework of goals, processes and solutions that can serve as a starting point for instructors in designing their own student-managed investment fund (SMIF) course experience that is relevant for all undergraduate business majors. Design/methodology/approach The design is suitable for a wide audience without prior equity investment expertise, lead to equity portfolio management competency and concentrate heavily on the understanding of the elements of a competitive business model. One noteworthy aspect of the proposed pedagogy is that it does not require a text, uses only real-world resources and is flexible in its execution. Findings The proposed pedagogy has achieved long-term success by consistently exceeding performance expectations. Originality/value According to the extant literature, many SMIFs are restricted to only a few students, develop skills unevenly across class participants, or are not formally organized or executed. There is a lack of in-depth and specific resources available in the extant literature to assist course designers in an SMIF design and execution. This manuscript fills this void by providing a detailed framework of goals, processes and solutions that can serve as a starting point for instructors in designing their own SMIF course experience.

The development of splitting method for incompressible fluid flows (SMIFs) during last 45 years is described. The hybrid explicit finite-difference scheme of SMIF method is based on modified central difference scheme (MCDS) and modified upwind difference scheme (MUDS) with special switch condition depending on the velocity sign and the signs of the first and second differences of transferred functions. Application of this method for solving some tasks is demonstrated. For example, the spatial flow around a sphere and a circular cylinder for homogeneous and stratified fluids [in a wide range of dimensionless parameters of the problem including the transitional regimes (2D-3D transition, laminar-turbulent transition in the boundary layer)], plane problem of fluid flows with a free surface, dynamics of vortex pair in a water, collapse of spots in stratified fluid, and the air, heat, and mass transfer in “clean rooms”.

Study of wave motions’ fluid is one of the most important and complex problems of modern hydrodynamics. A mathematical model for dynamics of incompressible uniform viscous liquid spots in the stratified medium is considered. This model is described by Navier–Stokes equations in Boussinesq approximation. Stratification component of the medium is saltiness. Bearing in mind that in such flows there are areas with large gradients of hydrodynamic parameters, required methods should possess such properties as a high order of accuracy, minimum scheme dissipation and dispersion, as well as monotony. To solve the task, the authors are developing a method of splitting by physical factors called as Splitting on physical factors Method for Incompressible fluid Flows (SMIF) possessing by the abovementioned properties. Four stages of splitting scheme are considered. This chapter provides a brief description of SMIF method. The test calculations and comparison with some theoretical and experimental data respect to the calculations of other authors are demonstrated.

This study provides a road map for creating and operating a student-managed investment fund (SMIF) as an experiential learning opportunity in commodity market analysis. We describe the reasons for implementing a SMIF and the benefits it offers relative to traditional simulation approaches. We outline the necessary steps for starting a SMIF and explain its organizational structure. We discuss a SMIF’s operation and main activities, which include recruitment, training, trading, and interaction with the client and alumni. The implications of participating in a SMIF are reviewed within a cost-benefit framework.

Background The submental island flap (SMIF) is frequently utilized as an alternative to free tissue transfer (FTT) in oral cavity reconstruction. Methods Studies directly comparing SMIF and FTT for oral cavity defects were included. Data were pooled with random-effects meta-analysis to calculate standardized mean differences and risk differences. Heterogeneity was evaluated with the I2 statistic. Results Five studies were included in the analysis. The aggregate sample sizes for SMIF and FTT cohorts were 122 and 127, respectively. SMIF was correlated with both reduced operative time and hospitalization by a large effect size. The rate of total flap loss was comparable. SMIF was associated with lower donor site morbidity. There was no difference in the rate of disease recurrence between the two procedures. Conclusions SMIF is associated with less operative time, shorter hospitalization, fewer perioperative complications, and potentially similar disease recurrence rates compared to FTT for the reconstruction of oral cavity defects.

The problem of dynamics of incompressible homogeneous viscous liquid spots in stratified fluid is considered. Stratification component of medium is saltiness. A mathematical model for this problem is described by the Navier-Stokes equations in the Boussinesq approximation. Bearing in mind that in such flows there are areas with large gradients of hydrodynamic parameters required methods should possess such properties as a high order of accuracy, minimum scheme dissipation and dispersion, as well as monotony. To solve the task, use the authors developed method of splitting by physical factors, the method SMIF (Splitting on physical factors Method for Incompressible Fluid flows) possessing by the above-mentioned properties. Fore steps splitting scheme is considered. This paper will provide a brief description of the method SMIF. The test calculations and comparison with some theoretical, experimental data and calculations of other authors will be demonstrated.The problem of dynamics of incompressible homogeneous viscous liquid spots in stratified fluid is considered. Stratification component of medium is saltiness. A mathematical model for this problem is described by the Navier-Stokes equations in the Boussinesq approximation. Bearing in mind that in such flows there are areas with large gradients of hydrodynamic parameters required methods should possess such properties as a high order of accuracy, minimum scheme dissipation and dispersion, as well as monotony. To solve the task, use the authors developed method of splitting by physical factors, the method SMIF (Splitting on physical factors Method for Incompressible Fluid flows) possessing by the above-mentioned properties. Fore steps splitting scheme is considered. This paper will provide a brief description of the method SMIF. The test calculations and comparison with some theoretical, experimental data and calculations of other authors will be demonstrated.

A wavelength-tunable all-fiber mode-locked erbium-doped fiber laser has been proposed and realized by using a supermode interference filter (SMIF). The SMIF is fabricated by splicing a segment of seven-core fiber (SCF) to two standard single-mode fibers. Since two supermodes of the propagating light are excited in the SCF, the transmission spectrum of the SMIF shows a clean broadband comb-shape characteristic. By bending the SMIF in the proposed mode-locked laser, the output spectrum can be continuously tuned in a wavelength range up to 22 nm while keeping mode-locking operation. The self-starting laser produces 230 fs pulses with a spectral width of 14 nm.

Purpose The submental artery island pedicled flap (SMIF) is an underused alternative for reconstruction of head and neck defects after tumor ablation. The purpose of this study was to perform a comparative evaluation of reconstructive outcomes based on surgical site and ablative defect volume in patients who underwent reconstruction with the SMIF versus the forearm free flap (FFF). Materials and Methods A retrospective cohort study of all patients with oral cavity and oropharyngeal defects reconstructed with the SMIF and a cohort of patients with similar volume defects reconstructed with the FFF were compared for oncologic safety and viability of equivalent reconstructive outcomes. All statistical comparisons were assessed by analysis of variance and Fisher exact test. Results Average age was 61.8 years in the SMIF group versus 57.9 years in the FFF group. The most common defect was located in the tongue, with squamous cell carcinoma being the most common pathology identified. Flap volumes were similar (SMIF, 38.79 cm3; FFF, 39.77 cm3). Significant comparative outcomes identified with SMIF versus FFF reconstruction included shorter anesthesia times (815 vs 1,209 minutes; P Conclusions This is the first study to compare the SMIF with the FFF for reconstruction of oral cavity defects based on ablative volume deficit. The SMIF is a viable surgical option compared with the FFF that can be considered oncologically safe in the N0 neck, allowing for an excellent esthetic reconstruction, with decreased operative time, hospital stay, and donor site morbidity.

Molecular orbital analysis depicts the CNC(nb) backbone of the smif (1,3-di-(2-pyridyl)-2-azaallyl) ligand as having singlet diradical and/or ionic character where electrophilic or nucleophilic attack is plausible. Reversible dimerization of (smif)Fe{N(SiMe3)2} (1) to [{(Me3Si)2N}Fe]2(μ-κ(3),κ(3)-N,py2-smif,smif) (2) may be construed as diradical coupling. A proton transfer within the backbone-methylated, and o-pyridine-methylated smif of putative ((b)Me2(o)Me2smif)FeN(SiMe3)2 (8) provides a route to [{(Me3Si)2N}Fe]2(μ-κ(4),κ(4)-N,py2,C-((b)Me,(b)CH2,(o)Me2(smif)H))2 (9). A 3 + 2 cyclization of ditolyl-acetylene occurs with 1, leading to the dimer [{2,5-di(pyridin-2-yl)-3,4-di-(p-tolyl-2,5-dihydropyrrol-1-ide)}FeN(SiMe3)2]2 (11), and the collateral discovery of alkyne cyclotrimerization led to a brief study that identified Fe(N(SiMe3)2(THF) as an effective catalyst. Nucleophilic attack by (smif)2Fe (13) on (t)BuNCO and (2,6-(i)Pr2C6H3)NCO afforded (RNHCO-smif)2Fe (14a, R = (t)Bu; 14b, 2,6-(i)PrC6H3). Calculations suggested that (dpma)2Fe (15) would favorably lose dihydrogen to afford (smif)2Fe (13). H2-transfer to alkynes, olefins, imines, PhN═NPh, and ketones was explored, but only stoichiometric reactions were affected. Some physical properties of the compounds were examined, and X-ray structural studies on several dinuclear species were conducted.

Attempted syntheses of (smif)(2)Ti (smif =1,3-di-(2-pyridyl)-2-azaallyl) based on metatheses of TiCl(n)L(m) (n = 2-4) with M(smif) (M = Li, Na), in the presence of a reducing agent (Na/Hg) when necessary, failed, but several apparent Ti(II) species were identified by X-ray crystallography and multidimensional NMR spectroscopy: (smif){Li(smif-smif)}Ti (1, X-ray), [(smif)Ti](2)(μ-κ(3),κ(3)-N,N(py)(2)-smif,smif) (2), (smif)Ti(κ(3)-N,N(py)(2)-smif,(smif)H) (3), and (smif)Ti(dpma) (4, dpma = di-2-pyridylmethyl-amide). NMR spectroscopy and K-edge XAS showed that each compound possesses ligands that are redox noninnnocent, such that d(1) Ti(III) centers AF-couple to ligand radicals: (smif){Li(smif-smif)(2-)}Ti(III) (1), [(smif(2-))Ti(III)](2)(μ-κ(3),κ(3)-N,N(py)(2)-smif,smif) (2), [(smif(2-))Ti(III)](κ(3)-N,N(py)(2)-smif,(smif)H) (3), and (smif(2-))Ti(III)(dpma) (4). The instability of (smif)(2)Ti relative to its C-C coupled dimer, 2, is rationalized via the complementary nature of the amide and smif radical dianion ligands, which are also common to 3 and 4. Calculations support this contention.

A series of Werner complexes featuring the tridentate ligand smif, that is, 1,3-di-(2-pyridyl)-2-azaallyl, have been prepared. Syntheses of (smif)(2)M (1-M; M = Cr, Fe) were accomplished via treatment of M(NSiMe(3))(2)(THF)(n) (M = Cr, n = 2; Fe, n = 1) with 2 equiv of (smif)H (1,3-di-(2-pyridyl)-2-azapropene); ortho-methylated ((o)Mesmif)(2)Fe (2-Fe) and ((o)Me(2)smif)(2)Fe (3-Fe) were similarly prepared. Metatheses of MX(2) variants with 2 equiv of Li(smif) or Na(smif) generated 1-M (M = Cr, Mn, Fe, Co, Ni, Zn, Ru). Metathesis of VCl(3)(THF)(3) with 2 Li(smif) with a reducing equiv of Na/Hg present afforded 1-V, while 2 Na(smif) and IrCl(3)(THF)(3) in the presence of NaBPh(4) gave [(smif)(2)Ir]BPh(4) (1(+)-Ir). Electrochemical experiments led to the oxidation of 1-M (M = Cr, Mn, Co) by AgOTf to produce [(smif)(2)M]OTf (1(+)-M), and treatment of Rh(2)(O(2)CCF(3))(4) with 4 equiv Na(smif) and 2 AgOTf gave 1(+)-Rh. Characterizations by NMR, EPR, and UV-vis spectroscopies, SQUID magnetometry, X-ray crystallography, and DFT calculations are presented. Intraligand (IL) transitions derived from promotion of electrons from the unique CNC(nb) (nonbonding) orbitals of the smif backbone to ligand π*-type orbitals are intense (ε ≈ 10,000-60,000 M(-1)cm(-1)), dominate the UV-visible spectra, and give crystals a metallic-looking appearance. High energy K-edge spectroscopy was used to show that the smif in 1-Cr is redox noninnocent, and its electron configuration is best described as (smif(-))(smif(2-))Cr(III); an unusual S = 1 EPR spectrum (X-band) was obtained for 1-Cr.

EUV Technology continues to make slow progress due to power source constraints. This extension will force customers to use 193 nm technology to bridge the gap until EUV can be fully utilized. As 193 nm technology are being used in smaller and smaller technology nodes, customers are imposing more and more stringent contamination requirements on the reticle environment to protect reticles from haze formation. Entegris' new E150 advanced 150mm Reticle SMIF Pod (RSP) has been designed to achieve several important goals: 1) Maintaining low relative humidity (RH) level after purge by advanced seal design and material choice; 2) Allowing cleaning and drying without disassembly; 3) Excellent electrostatic protection of reticles; 4) Modular design to allow flexibility to meet specific customer needs and take advantage of new resin technology. This paper presents the modular design concept and the test results of the RH retention, dryability, and electrical performance of the E150 150mm RSP.

This paper presents the design of a latch mechanism for wafer containers in a standard mechanical interface environment. For an integrated circuits fabrication factory, the standard mechanical interfaced wafer container is an effective tool to prevent wafers from particle contamination during wafer storage, transporting or transferring. The latch mechanism inside the container door is used to latch and further seal the wafer container for safety and air quality. Kinematic characteristics of the mechanism are established by analyzing the required functions of the mechanisms. Based on these characteristics, a methodology for enumerating feasible latch mechanisms is developed. New mechanisms with one degree-of-freedom and up to five links are generated. An optimum design is also identified with respect to the criteria pertinent to the application. The computer-aided simulation is also built to verify the design.

A method was developed to measure total hydrocarbons (THCs) to 1 part-per-trillion (ppt) concentration levels using gas chromatography. This method was applied to measuring THCs in a front opening universal pod (FOUP) under static and purge conditions. XCDA® purge gas was used for this experiment. XCDA gas is clean dry air (CDA) purified with Aeronex® purification technology to remove moisture to less than 1 part-per-billion (ppb) and hydrocarbons, sulfur, and siloxane contaminants to less than 1ppt. The experiment reveals that a FOUP's environment contains ppb levels of THCs under static conditions and ppt concentration levels of THCs under purge conditions. This test demonstrates that ppt purity gas can be delivered to and maintained in a FOUP. Finally, a silicon wafer is exposed to a FOUP environment under static and purge conditions. Desorption studies show that hydrocarbon contamination on the wafer is reduced under purge conditions.

This paper presents the design process for an innovative latch mechanism in a standard mechanical interfaced (SMIFed) wafer container, in which the manufactured integrated circuits are stored. An innovative latch mechanism is proposed and applied to the wafer container, such that the container door can be latched and air-tightly sealed during storage or transportation. The design process is divided into two stages. In the first stage, an output slot-cam is designed in order to generate decoupled fine motions of the output link. The issue is formulated as an optimization problem where the output link dimensions are optimized to minimize the resultant pin forces subject to an adequate transmission angle. In the second stage, the input slot-cam is designed to achieve that kinetic energy of the elastic gasket on the container lid is absorbed at a uniform rate. Finally, a numerical example and computer simulations are given to demonstrate the results of design process. It is believed that this work could aid in enhancing the performance and reliability of the latch mechanism in the SMIF environment.

The application of mini-environment and standard mechanical interface (SMIF) enclosure in the clean room can efficiently reduce airborne particles and isolate the personnel from the product. The purpose of this article is to reduce the recirculation zone and to maintain the positive pressure from the analysis results of the airflow field and pressure distribution of SMIF enclosure and mini-environment. The simulation code CFX will be used to study the flow field of air movement corresponding to the associated design parameters. The results show that proper drilling holes or slots can reduce the circulation zones of SMIF enclosure. The positive pressure of SMIF enclosure is mainly affected by inlet air flux, area of outlets, and leakage area. The calculated results can provide the design rules for SMIF robot inside the SMIF enclosure and reduce the particle accumulation during robot moving.

Proteins of the transforming growth factor beta(TGFbeta) superfamily regulate diverse cellular responses, including cell growth and differentiation. After TGFbeta stimulation, receptor-associated Smads are phosphorylated and form a complex with the common mediator Smad4. Here, we report the cloning of SMIF, a ubiquitously expressed, Smad4-interacting transcriptional co-activator. SMIF forms a TGFbeta/bone morphogenetic protein 4 (BMP4)-inducible complex with Smad4, but not with others Smads, and translocates to the nucleus in a TGFbeta/BMP4-inducible and Smad4-dependent manner. SMIF possesses strong intrinsic TGFbeta-inducible transcriptional activity, which is dependent on Smad4 in mammalian cells and requires p300/CBP. A point mutation in Smad4 abolished binding to SMIF and impaired its activity in transcriptional assays. Overexpression of wild-type SMIF enhanced expression of TGFbeta/BMP regulated genes, whereas a dominant-negative SMIF mutant suppressed expression. Furthermore, dominant-negative SMIF is able to block TGFbeta-induced growth inhibition. In a knockdown approach with morpholino-antisense oligonucleotides targeting zebrafish SMIF, severe but distinct phenotypic defects were observed in zebrafish embryos. Thus, we propose that SMIF is a crucial activator of TGFbeta signalling.

A new minienvironment for controlling the process area from ambient air contamination was designed and evaluated. The new design has a buffer zone between the ambient and the process zones. A parametric study of this design using a Computational Fluid Dynamics (CFD) method was conducted for various cases. A full-scale experimental model was fabricated. The evaluation was completed by measurements of airflow patterns, zone pressure differentials and particle concentration levels for the fabricated minienvironment. It is concluded that this new minienvironment is capable of maintaining a cleanliness of less than one particle per cubic meter, and the buffer zone is effective in preventing cross contamination between the process and the ambient zones.

This paper discusses the performance evaluation of a SMIF (Standard Mechanical Interface) system. A two-chamber experimental system is used with one chamber providing the test atmosphere of the cleanroom and the other providing the test atmosphere of the minienvironment. The cleanroom atmospher can be varied by adjusting the amount of particles injected into the chamber. Particle concentration ranges from 1,000/ft-3 to 10 million/ft3 can be created in the chamber to simulate different cleanroom conditions. The atmosphere of the second chamber is maintained at Class I or better equivalent by means of a self-powered ultra-low penetration air (ULPA) filter blower unit. By means of this system, the ability of the SMIF system to isolate the contaminants in the cleanroom atmosphere from the minienvironment atmosphere was measured. In addition, the particles added to the wafer during wafer cassette handling by the SMIF-Arm were also measured by a wafer scanner. The results indicate that the SMIF system tested is capable of providing extremely high isolation ratios in terms of its ability to isolate the cleanroom atmosphere from the atmosphere of the minienvironment. Isolation ratios in excess of 1 million to 1 or better have been measured. The measured particle per wafer per pass (PWP) numbers were generally around 0.02 or less for most wafers, with the average at 0.0118.

For solving of the Navier-Stokes equations describing 3D incompressible viscous fluid flows the Splitting on physical factors Method for Incompressible Fluid flows SMIF with hybrid explicit finite difference scheme second-order accuracy in space, minimum scheme viscosity and dispersion, capable for work in the wide range of Reynolds Re and internal Froude Fr numbers and monotonous based on the Modified Central Difference Scheme and the Modified Upwind Difference Scheme with a special switch condition depending on the velocity sign and the signs of the first and second differences of the transferred functions has been developed and successfully applied. At the present paper the description of the numerical method SMIF and it's application for simulation of the 3D separated homogeneous and density stratified fluid flows around a sphere are demonstrated.

Polyclonal antibodies were generated to the 105 kDa herring sperm motility initiation factor (SMIF) and used to explore the role of SMIF in sperm-egg interaction. Using sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting with SMIF antibodies, it was demonstrated that SMIF is present as a minor (4–7% of total chorion protein) component of the chorion. The major polypeptides in the chorion migrated at 117 kDa and in a grouping between 48–54 kDa, with other minor bands above and below. The only detectable glycosylated component was the 105 kDa band, which was resolved at two isoelectric points (8.22 and 8.31) after isoelectric focusing gel electrophoresis. Using antibodies to SMIF, fertilization was blocked, sperm motility was inhibited in vitro in the presence of solubilized SMIF and SMIF binding sites on sperm were localized. Lastly, SMIF was localized to the region of the herring egg that encircles the micropyle.

A 78-kDa spermatozoa motility inhibiting factor (SMIF) was purified from chicken (Gallus domesticus) seminal plasma by anion exchange (DE-53) followed by affinity chromatography on concanavalin A-Sepharose. The factor is thermostable and inhibited the spermatozoa motility in a dose dependent manner. In addition, SMIF inhibited the growth of gram negative bacteria, Pasteurella multocida but not gram positive Streptococcus equi. The factor lost its spermatozoa immobilizing property after treatment with trypsin, chymotrypsin or pepsin. The inhibition of SMIF by beta-mercaptoethanol suggest the involvement of disulfide bonds in its activity. Similarly, this property was lost in presence of chicken seminal plasma or incubating SMIF with anti-SMIF antibodies. Evidence is provided for the presence of a high molecular weight protein (> 100 kDa) in chicken seminal plasma that neutralizes the motility inhibiting property of SMIF. No significant decrease in spermatozoa ATP was observed in presence of SMIF suggesting that the loss of spermatozoa motility was due to factors other than depletion in cell's energy. Using anti-SMIF antibodies, a cross-reactive protein was identified in the blood, liver and reproductive tissues of chicken and the seminal plasma of cattle and buffalo. However, the cross-reactive protein failed to inhibit chicken spermatozoa motility. The significance of SMIF in chicken seminal plasma is discussed.

A thin films fabrication facility using minienvironments and product-handling automation was benchmarked to determine the extent to which isolating products from the cleanroom avoids contamination. Data were collected from tests that simulated production conditions while controlling random variables. The study found that isolation factors of at least 1000 were demonstrated by settling wafer data, and 10,000 by aerosol data. In general, lowered room airflow did not significantly degrade minienvironment cleanliness. In addition, the study investigated reliability, electrostatic charge and electromagnetic interference issues, and materials outgassing.

High efficient mask logistics as well as safe and high quality mask storage are essential requirements within an advanced lithography area of a modern logic waferfab. Fast operational availability of the required masks at the exposure tool with excellent mask condition requires a safe mask handling, safeguarding of high mask quality over the whole mask usage time without any quality degradation and an intelligent mask logistics. One big challenge is the prevention of haze on high advanced phase shift masks used in a high volume production line for some thousands of 248nm or 193nm exposures. In 2008 Infineon Dresden qualified a customer specific developed semi-bare mask storage system from DMSDynamic Micro Systems in combination with a high advanced mask handling and an interconnected complex logistic system. This high-capacity mask storage system DMS M1900.22 for more than 3000 masks with fully automated mask and box handling as well as full-blown XCDA purge has been developed and adapted to the Infineon Lithotoollandscape using Nikon and SMIF reticle cases. Advanced features for ESD safety and mask security, mask tracking via RFID and interactions with the exposure tools were developed and implemented. The stocker is remote controlled by the iCADA-RSM system, ordering of the requested mask directly from the affected exposure tool allows fast access. This paper discusses the advantages and challenges for this approach as well as the practical experience gained during the implementation of the new system which improves the fab performance with respect to mask quality, security and throughput. Especially the realization of an extremely low and stable humidity level in addition with a well controlled air flow at each mask surface, preventing masks from haze degradation and particle contamination, turns out to be a notable technical achievement. The longterm stability of haze critical masks has been improved significantly. Relevant environmental parameters like temperature, humidity, AMC (Airborne Molecular Contamination) and particles are controlled online within the system and monitored via the Cleanroom Monitoring System and iCADA RSM. The storage system is well conditioned, based on a fine adjusted heating and cooling concept whereby the desired temperature and humidity values are kept very stable even under high frequent mask transactions. The in-house developed RFID system and traceability of masks within the Infineon Dresden Lithotool landscape is a new and complex logistics improvement, decoupling masks from boxes, saving costs and time and reducing particles. The presented hardware and software solution shows how the potential of automation and improved production efficiency can be increased by such adapted systems even in a mature 200mm waferfab.

We carry out a theoretical investigation of the recently reported M(smif)(2) series1,2 and find a number of interesting phenomena. These include complex potential energy surfaces with near-degenerate stationary points, low-lying states, non-trivial electron configurations, as well as non-innocent ligand behavior. The M(smif)(2) exhibit a delicate balance between geometry and electronic structure, which has implications not only for their reactivity but also for controlling their properties through ligand design. We address methodological issues and show how conceptual quantities such as oxidation states and electronic configurations can be extracted through a simple analysis of the electron and spin densities-without a complicated examination of the underlying orbitals.

Sperm motility inhibiting factor (SMIF) has been isolated from boar seminal plasma by acetone fractionation and thin-layer chromatography on silica gel. Low molecular weight (5700 Da), maximal absorbance at 220 nm, significant thermostability, positive ninhidrin reaction and dominating acidic amino acid residues indicate the SMIF is a peptide and anionic. SMIF showed non-species-specific inhibition of sperm motility in microscopic studies. An antigenic species-specificity of SMIF was demonstrated. Immunofluorescence confirmed that the peptide was secreted by epithelial cells of the vesicle glands. No fluorescence was observed in other tissues of the boar's reproductive system. SMIF was associated with macromolecular protein fractions of seminal plasma and vesicle fluid. Whole plasma of boar semen showed a modulating effect on the inhibiting activity of SMIF. Adenosine receptor antagonist, in 10 mM concentration, as well as caffeine and theophylline, decreased the inhibitory activity of the peptide on sperm motility. SMIF significantly decreased the adenosine 5′,-triphosphate content of spermatozoa and inhibited growth of Gram-positive bacterial species. The lytic activity of SMIF against Micrococcus lysodeikticus (luteus) , observed by a turbidimetric method, suggests that SMIF could interact with the spermatozoa membrane. The results suggest that SMIF is a regulating peptide of boar seminal plasma.

Sperm motility inhibiting factor (SMIF), isolated from boar seminal plasma, injected i.p. into mice at a dose of 100 μg, inhibited the humoral immune response against T-cell dependent antigen (sheep red blood cells) in Cunningham tests. SMIF given in doses of 12–100 μg potentiated the proliferation of murine splenocytes stimulated by Concanavalin A but there was no dose-dependent effect. SMIF also affected the cell-mediated immune response against histocompatibility antigens in skin graft tests in mice. Immunofluorescence analysis showed that SMIF exists on the membranes of boar, bull, ram and human spermatozoa.

Floor space in a Class 1 or better cleanroom costs approximately $2000 to $3000 per square foot to construct. Operating costs for these rooms are equally expensive. It is also true that even the best cleanroom facility may be subverted by sources of contamination within the cleanroom itself. Due to these factors, many new semiconductor fabs are built with provisions to isolate wafer processing areas from the rest of the factory by means of various enclosures, which may be grouped into the category of wafer isolation technologies. These include cluster tools, clean-tool units mounted directly on equipment (microenvironments), and equipment surrounding clean air enclosures (minienvironments). For each configuration, critical considerations include wafer transport and loading. Wafer transport mechanisms must keep wafers stringently clean and protect wafers from breakage. Typical methods of wafer cassette transport include standard mechanical interface (SMIF) pods, run boxes, and open cassettes. This paper examines the relative cleanliness of various modes of accessing microenvironment enclosures at varying cleanliness levels of ambient air surrounding the microenvironment. Ambient air cleanliness tested ranges from Class 10 to Class 10,000. Wafer cleanliness is measured through the use of a wafer surface scanner to measure particles per wafer pass (PWP). Access methods tested include a swinging door, SMIF robot arm, flexible curtain, and Manual Access Port (MAP). (Manual Access Port and MAP are registered trademarks of Briner/Yeaman Engineering, Inc.)

The control of haze contamination on reticles has been gaining an ever-increasing focus because of its contribution to the huge yield loss in semiconductor manufacturing. Yield improvement through the reduction of haze on reticles has been a significant challenge as the use of 193nm light source and the shrinkage of line width on reticles. For a mass production IC manufacturing fab, an easy and practical solution is needed to prevent haze generation. In our previous study (Tseng et al., 2008), we demonstrated a practical and effective solution to reticle haze formation at a mass production DRAM factory. After implementing this solution, the number of wafers printed without haze development on reticles can be up to 150,000 wafers, and the maximum exposure dosage can be up to 9×10 8 mJ/cm 2 without the detection of any printable haze. Using the average data from more than 20 reticles, the average wafer printed before cleaning of reticle was more than 100,000 wafers. This solution has been proven to be effective in reducing the generation of haze on reticles. In current study, our focus is on further improvement of this haze solution and the ultimate goal is to reduce the haze generation effectively, but also economically. First, we use ultra low outgas material, antistatic PEEK, as the material of reticle carrier to perform the study and investigate its effect on haze generation. The total outgas data, leaching, electrical field shielding, and surface resistance data of different polymer materials are also compared. Secondly, we optimize the purging flow rate to reduce the running cost, but also maintain the performance. Our approach is to design purge nozzles, which can create a smooth flow field inside reticle SMIF pod (RSP) and make the maintenance of an ultra clean RSP environment with the smallest flow rate be possible. The results show the PEEK RSP with newly designed purge nozzles can provide great haze prevention result with a lower flow rate. Detailed data is provided and compared with previous design. By using this new solution, the number of wafers printed without haze development on reticles can be up to 300,000 wafers, and the maximum exposure dosage can be up to 1.2×10 9 mJ/cm 2 without the detection of any printable haze. The average wafer printed before cleaning of reticle was more than 170,000 wafers. This is a significant improvement to delay the generation of haze on reticles. The comparison of N 2 / XCDA performance based on wafer exposure shows that no significant difference can be observed.

Advanced photolithography tools use 193 nanometer wavelength light for conventional and immersion printing. The increased energy of 193 nm (ArF) light coupled with the higher absorption cross section of most materials has lead to a dramatic increase in the rate of haze formation as compared to previously used lithographic wavelengths (248 KrF and 365 nm i-line systems). It is well known that at this short wavelength photochemical reactions are enhanced leading to progressive defect formation, or haze, on optical surfaces within microlithography tools. Therefore, strict contamination control of the optics environment is needed to avoid cumulative effects. Such measures have been implemented in lithography tools both for the optics and for the reticle during exposure. However, the patterned side of the photomask is the most sensitive element in the litho optical path for haze growth, because it is in focus and small defects will show up as printing defects. Moreover, the reticle life time depends both on rigorous contamination control for expose and transport/storage conditions (both inside and outside of the lithography tool). The litho operating cost depends directly on reticle life time. It is imperative that the industry takes the required measures to improve the airborne molecular contamination levels both in the storage part of the photolithography tool and in devices used to transport reticles outside of the tool to slow down reticle haze Past studies have shown the large effects of humidity and AMC on haze growth during storage and exposure. Therefore, significant improvements in storage and exposure environment have been implemented by many fabs to reduce the frequency of haze failures. It has also been shown that outgassing from materials surrounding the mask can influence or cause haze. It is clear that the reticle must be adequately protected from contamination sources throughout the life cycle of the reticle (both inside and outside of the lithography tool). In this paper we examine improvements in the storage conditions of reticles inside the lithography tool as well as improvements in commercial SMIF pods used in fab storage and automated handling of reticles.

Sperm of the Pacific herring are immotile at spawning. Two egg-derived molecules are capable of initiating sperm motility. One is herring sperm activating protein(s) (HSAPs) and the other is sperm motility initiation factor (SMIF). These two motility initiators differ in their location and association with the chorion, and in thier isoelectric points and molecular weights. In this study we have investigated the roles of these two inducers with respect to motility and fertilization. Using computer analysis of sperm motility, we found that HSAPs, as well as the C-terminal HSAPs peptide, elicit a linear motility pattern, while SMIF induced a highly circular and asymmetric pattern. HSAPs induced a two-fold increase in intracellular calcium, whereas SMIF induced a four-fold increase of motility initiation. SMIF-exposed sperm, preloaded with BAPTA-AM, showed a more linear motility and this motility trajectory decreased with their fertilizing capability. The difference in intracellular calcium levels between HSAPs and SMIF is consistent with the observed linear and circular motility. In the absence of SMIF, HSAPs do not support fertilization. Fertilization is rescued in these experiments if SMIF is reintroduced. We propose that diffusible HSAPs are not essential for fertilization, but enhance sperm-egg collisions via linear motility. SMIF, which is bound to the micropylar region of the chorion, is required for fertilization and induces circular motility that is a prerequisite for sperm to enter the micropylar canal and fertilize the egg.

Use of specially designed reticle SMIF pods (RSPs) - with unique purge flow, internal dual-capture mechanism purifiers and an ultra-low humidity CDA purging system- have provided a practical solution to eliminate reticle haze for the useful life of the reticle in production environments. Prior publications, Kishkovich et al., described newly understood mechanisms of reticle haze formation based on chemical modification of quartz and chrome surfaces and have proposed solutions based on continual purge of the reticle environment with ultra-low humidity purified air [1]. In further publications they reported successful application of this solution in the field on single reticle-pod purge systems. [2] In this paper we provide guidance and advice for high volume manufacturing haze control practitioners, describing some challenges and solutions implemented on reticle stocker equipment, including considerations for materials of construction, purge flow levels and regulation, in-pod moisture/chemical purifiers, and on-tool flow measurement techniques.

Progressive mask defects are a critical mask-reliability issue in DUV lithography. It is well known that the majority of the defects are ammonium sulfates. We have found using ToF-SIMS that metallic atoms are localized at ammonium-sulfate defects on the mask surface, can influence the growth of the defects. Carbon compounds containing nitrogen atoms are also localized at the some defects. These carbon compounds are the result of the adsorption of organic volatiles outgassing from a reticle SMIF pod. Metal residues and organic contamination on a photomask as well as airborne acidic and basic contamination must be controlled to avoid progressive defects on photomasks.