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School films depict educational leaders as lone miracle workers. Students of colour and/or from low socio-economic backgrounds are shown as victims in need of a saviour, who appears in the form of a (usually White) teacher who lacks the qualifications and experience to work with students living in poverty. "Freedom Writers," "Music of the Heart," and "Dangerous Minds" teach moviegoers (the public) that these students require only underqualified, inexperienced, caring, Caucasian teachers, even though the research shows otherwise.

In 2010, the National Dropout Prevention Center for Students with Disabilities (NDPC-SD) partnered with the West Virginia Department of Education Office of Special Programs to provide intensive technical assistance to 12 school districts to help them design and implement evidence-based programs to increase the graduation rates of students with disabilities. In this article, we describe the initiative and interventions implemented in five districts that successfully decreased dropout and increased graduation among students with disabilities. We provide graduation data from the 2008-2009 school year along with graduation data from 2012-2013 to demonstrate the gains made in these rural school districts. All names of districts and schools have been changed.

Multilayer coating results are discussed for the primary and secondary mirrors of the micro-exposure tool (MET): a 0.30 NA lithographic imaging system with a 200 [micro]m x 600 [micro]m field of view at the wafer plane, operating in the extreme ultraviolet (EUV) region at an illumination wavelength around 13.4 nm. Mo/Si multilayers were deposited by DC-magnetron sputtering on large-area, curved MET camera substrates. A velocity modulation technique was implemented to consistently achieve multilayer thickness profiles with added figure errors below 0.1 nm rms demonstrating sub-diffraction-limited performance, as defined by the classical diffraction limit of Rayleigh (0.25 waves peak to valley) or Marechal (0.07 waves rms). This work is an experimental demonstration of sub-diffraction-limited multilayer coatings for high-NA EUV imaging systems, which resulted in the highest resolution microfield EUV images to date. OCIS codes: 220.0220, 220.3740, 240.5770, 340.7440, 310.0310.

The high-spatial frequency roughness of a mirror operating at extreme ultraviolet (EUV) wavelengths is crucial for the reflective performance and is subject to very stringent specifications. To understand and predict mirror performance, precision metrology is required for measuring the surface roughness. Zerodur mirror substrates made by two different polishing vendors for a suite of EUV telescopes for solar physics were characterized by atomic force microscopy (AFM). The AFM measurements revealed features in the topography of each substrate that are associated with specific polishing techniques. Theoretical predictions of the mirror performance based on the AFM-measured high-spatial-frequency roughness are in good agreement with EUV reflectance measurements of the mirrors after multilayer coating. OCIS codes: 120.6660, 340.7470, 310.6860.

An ion-beam deposition system has been used to fabricate Mo-Si multilayer coatings for masks and imaging optics to be used for extreme-ultraviolet lithography. In addition to high reflectivity and excellent profile control, ion-beam deposition has the capability to smooth rough substrates. For example, we achieved reflectivity of 66.8% on a substrate with 0.39-nm roughness. Smoothing can be further enhanced with a second ion source directed at the multilayer coating. The smoothing capabilities relax the requirement on the finish of the mirror and the mask substrates and could dramatically reduce the cost of these components. Thickness profile control is in the [+ or -] 0.01% range, and the figure error added to the mirror substrate by errors in the multilayer thickness is less than 0.1 nm. Peak reflectivities obtained on smooth substrates are 67.5-68.6%. OCIS codes: 310.0310, 110.3960, 340.7470, 340.0340.

A method is described for planarizing reticle substrates with smoothing layers. An ion-assisted Mo-Si smoothing-layer approach shows promise for dealing with defects.

The transmittance and the optical constants of SrF2 thin films, a candidate material for multilayer coatings operating in the extreme ultraviolet and soft x-rays, have been determined in the spectral range of 25-780 eV, in most of which no experimental data were previously available. SrF2 films of various thicknesses were deposited by evaporation onto room-temperature, thin Al support films, and their transmittance was measured with synchrotron radiation. The transmittance as a function of film thickness was used to calculate the extinction coefficient k at each photon energy. A decrease in density with increasing SrF2 film thickness was observed. In the calculation of k, this effect was circumvented by fitting the transmittance versus the product of thickness and density. The real part of the refractive index of SrF2 films was calculated from k with Kramers-Krönig analysis, for which the measured spectral range was extended both to lower and to higher photon energies with data in the literature combined with interpolations and extrapolations. With the application of f- and inertial sum rules, the consistency of the compiled data was found to be excellent. [ABSTRACT FROM AUTHOR]

Phase defects that introduce errors in the printed image are one of the major yield limiters for reticles in extreme-ultraviolet lithography. The basis for a reticle is a mask blank, consisting of an ultra-low-expansion substrate and a reflective multilayer stack that is made up of Mo and Si. A potential methodology for repairing phase defects in these mask blanks is to locally irradiate it with a high-resolution electron beam to induce structural deformations that cancel out the distortion of the multilayer. We present experimental and modeling results that show that the interaction of an electron beam with a mask blank can only be understood when the contraction of the multilayer through silicide formation and substrate compaction, as well as the mechanical response of the mask blank, are considered. One of the consequences is that electron beams with energies around 10 keV that are less than 20 nm in diameter induce depressions in multilayers made up of 50 Mo/Si bilayers that have a surprisingly large diameter of about a micrometer. Our models suggest that these unacceptably large diameters can only be reduced if the compaction of the substrate is prevented. [ABSTRACT FROM AUTHOR]

Extreme-ultraviolet lithography requires expensive multilayer-coated Zerodur or ULE optics with extremely tight figure and finish specifications. Therefore it is desirable to develop methods to recover these optics if they are coated with a nonoptimum multilayer films or in the event that the coating deteriorates over time owing to long-term exposure to radiation, corrosion, or surface contamination. We evaluate recoating, reactive-ion etching, and wet-chemical techniques for the recovery of Mo/Si and Mo/Be multilayer films upon Zerodur and ULE test optics. The recoating technique was successfully employed in the recovery of Mo/Si-coated optics but has the drawback of limited applicability. A chlorine-based reactive-ion etch process was successfully used to recover Mo/Si-coated optics, and a particularly large process window was observed when ULE optics were employed; this is an advantageous for large, curved optics. Dilute HCl wet-chemical techniques were developed and successfully demonstrated for the recovery of Mo/Be-coated optics as well as for Mo/Si-coated optics when Mo/Be release layers were employed; however, there are questions about the extendability of the HCl process to large optics and multiple coat and strip cycles. The technique of using carbon barrier layers to protect the optic during removal of Mo/Si in HF:[HNO.sub.3] also showed promise. OCIS codes: 230.4170, 220.4610, 240.0240, 310.0310, 110.3960, 260.7200.