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We are developing a modular (scanning) transmission electron microscope (S)TEM, referred to as NanoMi, which is released under an open source license by the National Research Council, Canada; see for updates. The electron microscope (EM) is a critical enabling tool in the physical, materials and biological sciences but its impact could be increased by the availability of an easy-to-build, customizable instrument capable of modest resolution and suitable for electron beam lithography, specialized experiments and for training personnel. An instrument that can be built for ~50 k$ and ~1 year of student time would fulfill these requirements in many laboratories around the world. Here we describe an initial design of such an instrument.

Multi-probe scanning tunneling microscopy can play a role in various electrical measurements and characterization of nanoscale objects. The consistent close placement of multiple probes relies on very sharp apexes with no other interfering materials along the shank of the tip. Electrochemically etched tips can prepare very sharp apex tips; however, other asperities on the shank can cause interference and limit the close positioning of multiple tips to beyond the measured radii. Gallium focused ion beam (FIB) milling is used to remove any interfering material and allow closely spaced tips with a consistent yield. The tip apex radius is evaluated with field ion microscopy, and the probe spacing is evaluated with STM on hydrogen terminated silicon surfaces. FIB prepared tips can consistently achieve the measured probe to probe spacing distances of 25 nm–50 nm.

While many remote water pumping systems exist (e.g. mechanical windmills, solar photovoltaic, wind-electric, diesel powered), few combine both the wind and solar energy resources to possibly improve the reliability and the performance of the system. In this paper, off-grid wind turbine (WT) and solar photovoltaic (PV) array water pumping systems were analyzed individually and combined as a hybrid system. The objectives were to determine: (1) advantages or disadvantages of using a hybrid system over using a WT or a solar PV array alone; (2) if the WT or solar PV array interfered with the output of the other; and (3) which hybrid system was the most efficient for the location. The WT used in the analysis was rated at 900 W alternating current (AC). There were three different solar PV arrays analyzed, and they were rated at 320, 480, and 640 W direct current (DC). A rectifier converted the 3-phase variable voltage AC output from the WT to DC before combining it with the solar PV array DC output. The combined renewable energies powered a single helical pump. The independent variable used in the hybrid WT/PV array analysis was in units of W/m 2 . The peak pump efficiency of the hybrid systems at Bushland, TX occurred for the 900 W WT combined with the 640 W PV array. The peak pump efficiencies at a 75 m pumping depth of the hybrid systems were: 47% (WT/320 W PV array), 51% (WT/480 W PV array), and 55% (WT/640 W PV array). Interference occurred between the WT and the different PV arrays (likely due to voltage mismatch between WT and PV array), but the least interference occurred for the WT/320 W PV array. This hybrid system pumped 28% more water during the greatest water demand month than the WT and PV systems would have pumped individually. An additional controller with a buck/boost converter is discussed at end of paper for improvement of the hybrid WT/PV array water pumping system.

For several years, many types of solar powered water pumping systems were evaluated, and in this paper, diaphragm and helical solar photovoltaic (PV) powered water pumping systems are discussed. Data were collected on diaphragm and helical pumps which were powered by different solar PV arrays at multiple pumping depths to determine the pumping performance, efficiency, and reliability of the different systems. The highest diaphragm pump hydraulic efficiency measured was ∼48%, and the highest helical pump hydraulic efficiency measured was ∼60%. The peak total system efficiency (e.g. solar radiation to pumped water) measured for the diaphragm and helical pumps were ∼5% and ∼7%, respectively (based on PV modules with ∼12% efficiency). The daily water volume of the three-chamber high head diaphragm pump performed better than the dual-chamber high head diaphragm pump (∼5 to ∼100% depending on PV array input power and pumping depth). Use of a controller was shown to improve the quad diaphragm pump performance below a solar irradiance of 600 W/m 2 (20 m head) to 800 W/m 2 (30 m head). While diaphragm pumps made mostly of plastic demonstrated similar to much better pumping performance than diaphragm pumps made with a high proportion of metal, the metal pumps demonstrated a longer service life (>2 years) than the plastic pumps service life (

Mechanically detected spin resonances The interaction of spins in a sample with a magnetic field can generate forces that can be sensed with cantilever probes. Losby et al. measured the resonance signals at room temperature with a micromechanical torque magnetometer. The difference between two applied radio-frequency signals corresponded to the mechanical frequency of the resonator. This approach revealed the vortex core dynamics of the ferri-toferro–magnetic transition in a micrometer-sized yttrium-iron-garnet single-crystal disk. Science , this issue p. 798

Electrical conductivity measurements were performed on structurally anisotropic thin films deposited using the glancing angle deposition apparatus [K. Robbie and M. J. Brett, J. Vac. Sci. Technol. A 15, 1460 (1997); K. Robbie, J. Sit, and M. J. Brett, J. Vac. Sci. Technol. B 16, 1115 (1998); K. Robbie and M. J. Brett, US Patent No. 5,866,204 (2 February 1999)]. The films were comprised of bilayers of titanium over silica, engineered as a chevron morphology. Samples were evaporated at various incident vapor deposition angles α, in order to investigate the effects of morphology and voiding on the behavior of conductivity. A rapid decline in the conductivity, accompanied by an increase in conduction anisotropy in the plane of the substrate, was observed with increasing α. A random walk model was developed to model the transport properties of the films, and applied to microstructures predicted by a three-dimensional ballistic thin film simulator. In order to generate reasonable agreement between the modeling ...

A method of producing relatively monodisperse, small-diameter (sub-500 nm diameter) aerosol fibers is described. This method involves the separation of porous thin films from their substrate. It was found that fibers with diameters of less than several hundred nm and lengths of several micrometers can be formed that do not adhere to one-another. Two μ m thick columnar thin films were fabricated and processed, yielding aerosol fibers with lengths up to 2 μm and diameters up to 170 nm. Diameter and length distributions of a collected aerosol showed that a broad range of fiber lengths and diameters are formed by this method. Further modification of the method, however, is expected to greatly narrow the range of effective diameters and lengths obtained.

Recent experimental work by a number of researchers has demonstrated that unusual high porosity thin films may be obtained in physical deposition systems by combining glancing angle deposition with in situ substrate motion control. The microstructure of these films consists of isolated columns engineered into shapes such as helices, posts, or chevrons. Due to the isolated nature of the columns, the films present a unique opportunity to study fundamental thin film growth behavior and, in particular, the influence of the self-shadowing mechanism in three dimensions. Apart from this academic motivation, there is the need to characterize the physical constraints imposed on the engineering of these films. In particular, this study will have implications for the realization of isolated, periodically arranged nanostructures envisioned for certain applications such as photonic band gap crystals. Results from an ongoing study of growth dynamics, morphology, porosity, and scaling behavior, and the dependence of these features on deposition parameters are presented.

The effectiveness of debris reduction using magnetically guided pulsed laser deposition (MGPLD) is reported here. KrF laser pulses (248 nm) of 100 mJ energy were focused to intensities of 6×109 W/cm2 onto the surface of a copper or a carbon source target and a magnetic field of 0.3 T as used to steer the plasma around a curved arc of 0.5 m length to the deposition substrate. Debris counts were compared for films produced by the MGPLD and conventional PLD (nonguided) techniques. A significant reduction in particulates of size greater than 0.1 μm was achieved using MGPLD. For the copper films, particulate count was reduced from 150 000 particles/cm2/nm to 50 particulates/cm2/nm and for diamond-like carbon thin films particulate count was reduced from 25 000 particles/cm2/nm to 1200 particles/cm2/nm.

We investigated the use of a novel class of porous thin films for the characterization of tapping mode atomic force microscope (AFM) tips. Chromium and titanium films were evaporated using the technique of glancing angle deposition (GLAD) onto rotating silicon substrates. The morphology of the resulting films consisted of isolated vertical posts of sub-micron size. These isolated topographical features are small enough to provide useful information about tip morphology and aid in assessing tip wear and damage. The films were imaged using an AFM, and previously published tip reconstruction algorithms were used to obtain three-dimensional tip functions. These compared well with envelope profiles determined from scanning electron microscope images of the tips.

Artificial vortex core pinning sites are induced in thin Permalloy disks by point exposure to as few as 10 000 ions from a focused Ga+ beam. These pinning sites yield a first-order change in the magnetization response of the disk. A single site can keep the vortex core pinned over an applied field range comparable to the vortex annihilation field of the unaltered disk. Several widely separated sites can work together to keep the core pinned in one place, while the Barkhausen effect is eliminated from the magnetization curve over a range approaching the saturation moment of the disk. © 2014 AIP Publishing LLC.

A new approach is described in the deposition of thin films for thermal barrier applications. Using controlled substrate motion, porous layers and capping layers were vacuum deposited in an alternating fashion, creating a new, multilayered film structure. Direct measurements of the thermal properties of these multilayers were made using the 3ω and Mirage techniques. In the 3ω technique, heat is introduced into the coating by an AC current flowing through an evaporated resistor with a frequency ω. A fit of resistor voltage as a function of frequency yields the thermal conductivity. In the Mirage technique, an oscillating temperature is induced immediately above the film using a pulsed laser. A second probe laser aligned parallel to the surface is deflected by these temperature variations, and the thermal diffusivity is then found by fitting amplitude and phase shift data to the solution of the three-dimensional diffusion equation. Typically, the 3ω and Mirage techniques measure thermal constants in directions normal and parallel to the substrate, respectively. Measurements using these methods led to estimates of a reduction in thermal diffusivity of as little as 9% of that of films deposited entirely at normal incidence. Thermal simulations of similar structures also predicted a substantial decrease in overall thermal conductivity. In a specific case, an improved conductivity of 18% of that of films deposited by standard techniques was estimated.

Pulsed laser deposition (PLD) has been used together with the Glancing Angle Deposition (GLAD) technique [1,2] for the first time to produce highly porous structured films. A laser produced carbon plasma and vapour plume was deposited at a highly oblique incident angle onto rotating Si substrates, resulting in films exhibiting high bulk porosity and controlled columnar microstructure. By varying the substrate rotation rate, the shape of the microcolumns can be tailored. These results extend the versatility of the GLAD process to materials not readily deposited by means of traditional physical vapour deposition techniques.

The production of highly porous films by oblique deposition has attracted recent attention because of the possible applications of such films. The morphology of obliquely evaporated films is thought to be determined mainly by the mechanisms of self-shadowing and surface diffusion. The thin film process simulator GROFILMS has been used to verify the importance of these effects, and clarify some aspects of how they interact to determine the final film morphology. Good agreement between simulations and actual films has been achieved. Temperature control of the film during deposition is shown to be an important consideration for the production of structurally engineered films.

We present a comprehensive study of nanoelectromechanical systems in pressurized fluids. Resonant responses and quality factors are monitored in five different gases and one liquid, in pressures ranging from vacuum to 20 MPa, in order to evaluate theoretical models of device-fluid interactions at the nanoscale. The traditional Newell picture of microresonator damping in different pressure regimes is found to be inadequate in describing nanoresonators in general. Damping at intermediate pressure ranges is better physically characterized by a Weissenberg number (which compares oscillation frequencies with fluid relaxation rates) than a Knudsen number (which compares mean free paths with device widths) and most adequately described by the Yakhot and Colosqui model. At high-pressure ranges, two models are found to give good agreement with data: the phenomenological model of vibrating spheres and the Sader and Bhiladvala model for the viscous regime. The latter is also successful in explicitly predicting pressure-dependent behavior of the viscous mass load and damping. We observe significant increases in damping due to the squeezed film (SF) of gas between the device and substrate as well as due to undercut (an unavoidable artifact of the standard fabrication technique); correcting the shape of the devices with a focused ion beam allows us to differentiate these two factors. Application of the SF model accounts well for additional damping at high pressures while only qualitatively agreeing at lower pressures. The extensive data collected allow additional insight into fundamental processes underlying fluid damping at the nanoscale, particularly in the intermediate- and high-pressure regimes.

Summary form only given. Intensity nonuniformities in an incident laser beam may cause corresponding variations in the ablation pressure. The variations in the ablation pressure should be less than a few percent in order for spherical targets to implode symmetrically and to be ignited in inertial confinement-fusion experiments. The uniformity requirements on the laser beam could be eased by the degree of lateral heat conduction and plasma-hydrodynamic motions occurring between the absorption and the ablation surfaces. Theoretically, the scaling of the smoothing on the standoff distance (D) between the absorption and the ablation surfaces and the intensity-modulation wavelength (L) is obtained in terms of heat conduction and plasma-fluid motions. Experiments were conducted with a 0.53-/spl mu/m, 1-ns (FWHM), Gaussian shaped laser beam focused onto thin polystyrene targets. The smoothing factor shows a clear exponential decrease as D/L increases.

Here we report a new sample preparation method for three-dimensional electron tomography. The method uses the standard film deposition and focused ion beam (FIB) methods to significantly reduce the problems arising from the projected sample thickness at high tilt angles. The method can be used to prepare tomography samples that can be imaged up to a ±75° tilt range which is sufficient for many practical applications. The method can minimize the problem of Ga+ contamination, as compared to the case of FIB preparation of rod-shaped samples, and provides extended thin regions for standard 2D projection analyses. Microsc. Res. Tech. 75:1165–1169, 2012. © 2012 Wiley Periodicals, Inc.

MEMS based laser projection is of high interest for automotive head-up displays and dashboard displays, as well as for an increasing number of personal mobile projection applications. These applications require scanning mirrors that offer high scan frequencies and wide scan angles while showing low power consumption. This paper presents a novel low-power high-Q scanning mirror that is vacuum encapsulated on wafer level and thereby exhibits Q-factors exceeding 145,000. A new glass forming process enables fabrication of glass wafers with inclined 3D-shaped windows needed to spatially separate the direct reflex from the projected image.

Micromechanical resonators are very useful for detection of magnetic torque. We have developed nanoscale torsional resonators fabricated within silicon nitride membranes, as a platform for magnetometry of nanoscale magnetic elements. We describe the rotational magnetic hysteresis of a 10 nm thick film deposited on a resonator, and a study of magnetic hysteresis in a single, 1 m diameter permalloy disk. The torsional resonator is patterned using a dual beam scanning electron/focused ion system. For the 1 m diameter disk, it is found to be possible to tune the conditions such that an apparent magnetic supercooling of vortex nucleation is observed, as would be suggested by the modified Landau theory of the C- to vortex-state switch as a first-order phase transition. Complementary transmission electron and Lorentz microscopy of the same structures have also been performed. © 2011 American Institute of Physics.

Thin films with microstructures controlled on a nanometer scale have been fabricated using a recently developed process called glancing angle deposition (GLAD) which combines oblique angle evaporation with controlled substrate motion. Critical to the production of GLAD thin films is the requirement for a narrow angular flux distribution centered at an oblique incidence angle. We report here recent work with low-pressure, long-throw sputter deposition with which we have succeeded in fabricating porous titanium thin films possessing “zig-zag,” helical, and “pillar” microstructures, demonstrating microstructural control on a level consistent with evaporated GLAD. The use of sputtering for GLAD simplifies process control and should enable deposition of a broader range of thin film materials.

In toxicology and industrial hygiene, fibrous aerosols have long been associated with health risks. Aerodynamic alignment with inhaled air streamlines allows long, cylindrical fibers to penetrate deep into the lung, whereas compact particles of similar mass are filtered out in the upper respiratory tract. For drug delivery applications, fibrous aerosols may thus enable a relatively large drug mass to be delivered to the distal regions of the lung. At present, the aerodynamic behaviors of fibers that influence deposition in the respiratory tract are discussed. Methods for generating monodisperse (in both diameter and length) fibrous aerosols and of tagging these aerosols with a UV absorbent material, both by physical vapor deposition, are outlined.

The ability to produce high aspect ratio particle aerosols (airborne fibres) is required in order to develop a thorough understanding of the parameters that affect the deposition of fibres in the mouth and throat. Such an ability is currently being developed. In this work, we produce monodisperse fibres from porous thin films by releasing small structures from a substrate. The development of a means to assay for these fibres is also discussed.

Summary form only given, as follows. The guiding of plasma produced by a KrF laser and Nd:YAG laser using straight and curved solenoidal magnetic field has been studied as a means of giving a debris free, controlled deposition source for the production of thin films. Details on the deflection and guiding of the laser produced plasma in curved and straight magnetic fields and initial coating results will be presented. These results will be presented and compared to predictions of plasma guiding using 2D and 3D numerical plasma simulation mode.

Electron tomography (ET) in a TEM has been widely used to characterize materials at sub-10 nm spatial resolution. The first example of tomographic imaging in an electron microscope was reported four decades ago. However, due to the fast development of processing capacity of modern computers it is only in the past few years that ET in (scanning) transmission electron microscopy ((S)TEM) has become a more viable option for investigating the morphologies, spatial distribution and chemical compositions of nanostructures., Proceedings of Microscopy & Microanalysis 2011, August 7-11, 2011, Nashville, Tennessee

A new fully three dimensional (3D) ballistic deposition simulator 3D-FILMS has been developed for the modeling of thin film deposition and structure. The simulator may be implemented using the memory resources available to workstations. In order to illustrate the capabilities of 3D-FILMS, we apply it to the growth of engineered porous thin films produced by the technique of GLancing Angle Deposition (GLAD).

A non-lithographic method of fabricating high-density arrays of nanometer-scale vertical columns was investigated. The use of oblique deposition techniques allows the fabrication of isolated vertical columns in a single-step evaporation process without the need for either pre- or post-deposition lithographic processing. Extreme oblique incidence deposition with computer controlled substrate motion was utilized to fabricate columns with diameters near 100 nm and densities exceeding 109 columns/cm2. The desired column geometry may be engineered through choice of deposition angle and substrate spin rate. In one potential application of these microstructures, arrays of vertical columns were fabricated from silicon and carbon and tested for field emission characteristics. Further studies were made on the use of ion milling to modify the tips of the nanocolumns in order to improve the field emission properties.

Recent experimental work has demonstrated that unique high porosity thin films may be ob- tained in physical deposition systems by combining glancing angle deposition with in situ sub-strate motion control [1-7]. The microstructure of these films consists of isolated columns engineered into shapes such as helices, posts, or chevrons. Due to the isolated nature of the columns, the films present a unique opportunity to study fundamental thin film growth behaviour and, in particular, the influence of the self shadowing mechanism in three dimensions. Apart from this academic motivation, there is the need to characterize the physical constraints imposed on the engineering of these films. In particular, this study will have implications for the realization of isolated, periodically arranged nanostructures envisioned for certain applications. Preliminary results from an ongoing study of growth dynamics, morphology, porosity, and scaling behaviour, and the dependence of these features on deposition parameters are presented below.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Unique thin film microstructures have been fabricated with the Glancing Angle Deposition (GLAD) technique. These porous,thin films can be engineered with a variety of different morphologies to sub-micron dimensions, including helical, post, andchevron or zigzag microstructures. This paper reports some recent results in study and application of films deposited usingGLAD, namely: the use oflow pressure, long throw sputtering to produce porous titanium films; deposition ofporous, structuredZr02 films for use as thermal barriers; and measurement of the mechanical response of chiral or "microspring" thin films.Keywords: glancing angle deposition, thermal barrier, porous films, sputtering, mechanical properties 1. INTRODUCTION The Glancing Angle Deposition (GLAD) technique has been used to fabricate thin films by physical vapour deposition"2'3.This technique involves the deposition ofthin films onto unheated substrates oriented at highly oblique angles to the vapourflux. Under these conditions, two main mechanisms dominate the growth process: enhanced self-shadowing and limitedadatom diffusion3'4'5. When flux first arrives at the substrate, the film begins nucleating at the surface, and as additional fluxreaches the substrate, areas of previous film growth physically shadow the areas behind them. This initiates the formation ofnanometer scale, columnar structures. Because the substrates are unheated, the diffusion length of the adsorbed atoms islimited, and they do not fill in the areas which were shadowed. As the film further evolves, it develops into isolated columnsof material which can be grown with a variety of different microstructures through the utilization of computer controlledsubstrate motion. These microstructures include arrays of posts, zig-zags, helices, periodically bent nematics6'7 (s-shapes)and many other morphologies (sometimes called Sculptured Thin Films2), with control over the shape attainable on ananometer scale. Whereas earlier researchers have reported film deposition at oblique incidence4'5'8 (near 700 from

A new approach to deposition of thin films for thermal barrier applications is described. During electron beam evaporation, the extreme shadowing effect that is present at highly oblique incidence is employed to introduce porosity into thin films of zirconia. Using controlled substrate motion a solid capping layer may be applied to these porous films. By depositing layers of porous material and capping in an alternating fashion a new structure is produced which warrants evaluation as an improved thermal barrier coating.

Optical interferometric techniques are used for absolute (calibrated) displacement measurements of focused ion beam (FIB)-fabricated nanoelectromechanical systems (NEMS). FIB nanomachining of bulk Si gives rapidly prototyped cantilever and doubly clamped beam devices. Ion impingement from orthogonal directions allows tailoring of deep, undercut-free gaps between the device layer and the bulk, in turn allowing large amplitude NEMS oscillatory motion, access to a nonlinear readout regime and a new calibration method for optical interferometric displacement detection. The measurements are sensitive enough to determine the thermomechanical noise floor of a bulk FIBed NEMS device with a displacement sensitivity of 166 fm Hz−½, limited by the combination of optical shot noise and detector dark current. This sensitivity, comparable to the state of the art for free-space optical interferometry of NEMS, validates the robustness of the bulk FIB fabrication technique for rapid prototyping of nanoscale mechanical devices.

Although focused ion beam (FIB) milling has previously been used for fabrication of compliant nanostructures and devices, few instances of FIB nanomachining of such devices out of bulk materials have been reported. We use FIB to fabricate nanoelectromechanical systems (NEMS) devices out of bulk materials. Ion impingement from multiple directions allows sculpting with considerable three-dimensional control of device shape, including tapering and notching. Finite-element modeling of device frequencies agrees with optical interferometric measurements, including for the effect of a localized notch. We envision that bulk FIB fabrication will be useful for NEMS prototyping, milling of tough-to-machine materials and generalized nanostructure fabrication with three-dimensional shape control.

Magnetic torque is used to actuate nano-torsional resonators, which are fabricated by focused-ion-beam milling of permalloy coated silicon nitride membranes. Optical interferometry is used to measure the mechanical response of two torsion modes at resonance, which is proportional to the magnetization vector of the nanomagnetic volume. By varying the bias magnetic field, the magnetic behavior can be measured with excellent sensitivity ($\approx 10^8 \mu_B$) for single magnetic elements., Comment: 8 pages preprint, 4 figures, accepted to Appl. Phys. Letters

We describe the fabrication of porous chevron thin films deposited at glancing incidence and report some common growth peculiarities of the microstructure. In particular, the second (and additional) chevron arms of porous chevron thin films are consistently inclined at angles significantly greater than the corresponding first arms. This effect is observed in both real and simulated films and has important implications in the fabrication of optical coatings. A simple theoretical model is developed to describe this effect, and a technique for achieving consistent column angles is presented.

A novel three-dimensional (3D) ballistic deposition simulator 3D-FILMS has been developed for the modeling of thin film deposition and structure. The simulator features a ballistic transport algorithm to model incident species with angular distributions appropriate to physical vapor deposition systems. Two-tiered data structuring is employed in order to enable the simulator to run using memory resources available to workstations. The simulator has been applied to a unique class of thin films grown by the technique of glancing angle deposition (GLAD). These films exhibit low bulk density due to an internal structure consisting of isolated microcolumns, which can be engineered into a variety of 3D forms. Because of their inherent 3D morphology, created by a combination of complex substrate motion and 3D shadowing, GLAD films represent an ideal test subject for 3D simulation. Scanning electron microscope images of films are presented together with simulation results, which correctly reproduce aspects of colu...

A nanoindentation technique has been applied to demonstrate the mechanical actuation of thin films fabricated by glancing angle deposition. The films were comprised of a porous layer whose microstructures consisted of helical columns that resembled springs. Surmounting the porous layer was a dense capping layer which served to redistribute the force of the nanoindenter tip and prevent it from penetrating the microstructured film. Atomic force microscope images and force versus displacement curves confirmed that there was an elastic regime to the displacements in the films when low forces were applied. The loading behavior of the porous films was compared with that of dense, unstructured films and revealed a marked difference between the two. A study of the measurements and results enabled such properties as the spring constant and resonant frequencies to be estimated, establishing a basis for future developments and applications in wave-type devices or resonators constructed from these microstructured thin films.

Measurements of x-ray conversion efficAncies9have been made for plasmas produced by KrF laser pulses at intensities of 2.5-7.5x10 ''W cm Initial measurements of x-ray fluence have been made using a simple set of filtered x-ray diodes and an x-ray calorimeter for targets with atomic numbers from 4 to 82. More detailed measurements have been made of three elements: aluminum, titanium and gold. These have included measurements of the angular dependence of emission, the spectral characteristics of emission in the 100-1000 eV range and time dependent measurements of the spectrum using an x-ray streak camera. The angular and spectral characteristics have been used to more accurately determine the energy conversion efficiency for these elements.