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Dec 2002

Volume 73, Issue 12, pp. 4057-4404

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back to top CONDENSED MATTER; MATERIALS

Instrumentation for plasma immersion ion implantation

R. López-Callejas, R. Valencia-Alvarado, A. E. Muñoz-Castro, O. G. Godoy-Cabrera, and J. L. Tapia-Fabela

Rev. Sci. Instrum. 73, 4277 (2002); http://dx.doi.org/10.1063/1.1517144 (6 pages) | Cited 4 times

Online Publication Date: 21 November 2002

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Plasma immersion ion implantation (PIII) has proved to be a good method to implant ions into materials in order to modify their surface properties. In this article, we describe the design and construction of a small and low cost PIII device. The instrumentation consists of: (i) a simple plasma immersion experimental setup for ion implantation based on direct current glow discharges, (ii) a 25 kV pulse generator, (iii) an electrical probe system endowed with a guard to carry out diagnostics of the plasma parameters, and (iv) an automatic spectroscopy system for determining the plasma temperature. A study of the sheath expansion has been considered in order to fulfill the requirements of electron temperature, plasma density, high voltage bias, pulse frequency, and pulse duration for an adequate PIII process. © 2002 American Institute of Physics.
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52.77.Dq Plasma-based ion implantation and deposition
81.65.-b Surface treatments
61.72.up Other materials
52.80.Hc Glow; corona

Design and capabilities of a cluster implantation and deposition apparatus: First results on hillock formation under energetic cluster ion bombardment

V. N. Popok, S. V. Prasalovich, M. Samuelsson, and E. E. B. Campbell

Rev. Sci. Instrum. 73, 4283 (2002); http://dx.doi.org/10.1063/1.1518790 (5 pages) | Cited 13 times

Online Publication Date: 21 November 2002

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A description, advantages, and capabilities of a cluster implantation and deposition apparatus supplied by a pulsed cluster source from gaseous precursors are presented. A number of possible in situ and ex situ experimental methods to study cluster–surface collisions and modified substrate surfaces are discussed. Test experiments on cluster production show formation of Ar, N2, and O2 clusters with size up to 150 atoms for Ar and 60–70 molecules for the other gases. The possibility of cluster mass selection and acceleration up to 25 keV is reported. Nanosize hillock formation was found as a result of cluster–surface collisions with pyrolytic graphite and indium–tin–oxide. It is suggested that the hillocks’ parameters such as size and density per surface area can be controlled by varying the implantation parameters and substrate material and thus provide a promising technique for nanoscale surface modification. © 2002 American Institute of Physics.
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68.49.-h Surface characterization by particle-surface scattering
61.72.up Other materials
81.15.Jj Ion and electron beam-assisted deposition; ion plating
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
68.35.B- Structure of clean surfaces (and surface reconstruction)

Generation of 600 T by electromagnetic flux compression with improved implosion symmetry

Y. H. Matsuda, F. Herlach, S. Ikeda, and N. Miura

Rev. Sci. Instrum. 73, 4288 (2002); http://dx.doi.org/10.1063/1.1520733 (7 pages) | Cited 14 times

Online Publication Date: 21 November 2002

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We have developed a device for generating ultrahigh magnetic fields by means of electromagnetic flux compression. The device that we call “feed gap compensator” is a flux concentrator that consists of a thick-walled copper cylinder with a number of thin radial slits. This is inserted between the primary coil and the liner; it has resulted in a substantial improvement of the implosion symmetry that is normally disturbed by the feed gap of the primary coil. A maximum field exceeding 600 T can be generated reproducibly by using this device. Because of the improved symmetry of the liner motion, we observed turnaround phenomena not only in the wave form of the magnetic field but also in the photographs of the liner that are taken by a high-speed image converter camera. The final implosion speed and the turnaround radius have been determined by calculating the magnetic flux from a combination of framing camera data and the measured field. It is confirmed that the turnaround field is a function of the implosion speed; this function is given by the particle speed of the shock wave associated with the pressure pulse induced by the magnetic field. Further optimization of the flux compression system is discussed with a view to obtaining higher fields that are suitable for application in experiments. © 2002 American Institute of Physics.
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07.55.Db Generation of magnetic fields; magnets

A time-of-flight resonance ionization mass spectrometer for elemental analysis of precious metals in minerals

S. S. Dimov, S. L. Chryssoulis, and R. H. Lipson

Rev. Sci. Instrum. 73, 4295 (2002); http://dx.doi.org/10.1063/1.1518146 (12 pages) | Cited 2 times

Online Publication Date: 21 November 2002

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An instrument for time-of-flight resonance ionization mass spectrometry (TOF-RIMS) developed at the Advanced Mineral Technology Laboratory (Ontario, Canada) is described which has been applied to the quantitative trace analysis of metals in minerals. The instrument incorporates new pulsed ion optics which provide fast switching of polarity and potentials of acceleration and ion lens optics between the two consecutive laser ablation and laser photoionization steps. Pulsed mode operation allows the time-of-flight mass spectrometer to be operated at higher laser ablation powers with more efficient suppression of the primary ions which are a source of noise that degrades the ultimate sensitivity of detection. The performance of the TOF-RIMS apparatus was assessed by analyzing trace amounts of gold (Au) in sulphide, iron oxide, and silicate mineral samples. Quantification of the TOF-RIMS measurements was established on the basis of calibration curves obtained using reference samples covering three orders of magnitude in concentration. Reproducible minimum detection limits (2σ) of ⩽10 parts per billion with a precision of ∼±15% were obtained. © 2002 American Institute of Physics.
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82.80.Rt Time of flight mass spectrometry
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
07.75.+h Mass spectrometers

Ultraviolet phase-modulated ellipsometer

Enric Garcia-Caurel, Jean Luc Moncel, Francis Bos, and Bernard Drévillon

Rev. Sci. Instrum. 73, 4307 (2002); http://dx.doi.org/10.1063/1.1518788 (6 pages)

Online Publication Date: 21 November 2002

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A phase modulated ellipsometer working in the spectral range from the visible (1.5 eV) to the far ultraviolet (9.5 eV) is described and some preliminary examples of applications are shown in order to illustrate its sensitivity and accuracy. The optical configuration of the ellipsometer consists of a light source, a monochromator, a polarizer, a photoelastic modulator, a sample holder, an analyzer, and two detectors. This system has been adapted into air sealed chambers and functions under vacuum conditions to prevent absorption of the far ultraviolet radiation by atmospheric gases. The described apparatus makes it possible to perform both ex situ and in situ real time measurements. Working in the far ultraviolet (FUV) (6–10 eV), opens the interesting possibility of determining the optical properties of materials at photon energies of 6.5 and 9.5 eV, which correspond to the laser sources used in the photolithographic process. It can be anticipated that FUV phase modulated ellipsometry will appear as a useful tool for material research and characterization in the semiconductor industry. © 2002 American Institute of Physics.
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07.60.Fs Polarimeters and ellipsometers
back to top CHEMISTRY

A nanosecond near-infrared step-scan Fourier transform absorption spectrometer: Monitoring singlet oxygen, organic molecule triplet states, and associated thermal effects upon pulsed-laser irradiation of a photosensitizer

Lars Klembt Andersen and Peter R. Ogilby

Rev. Sci. Instrum. 73, 4313 (2002); http://dx.doi.org/10.1063/1.1517148 (13 pages) | Cited 3 times

Online Publication Date: 21 November 2002

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A step-scan Fourier transform (FT) near infrared (IR) spectrometer has been used to record nanosecond time-resolved absorption spectra of singlet molecular oxygen (a1Δg→b1Σg+) created by pulsed-laser irradiation of a photosensitizer dissolved in a solvent. In addition to oxygen’s a→b transition at ∼5200 cm−1, other laser-induced changes in absorbance can be monitored over the spectral range ∼4000–11 000 cm−1. These include transients derived from the singlet oxygen sensitizer, and examples are provided with triplet state absorption spectra of several molecules in benzene as well as water. In this report, issues pertinent to the use of a step-scan FT spectrometer to monitor weak laser-induced near-IR signals are discussed. Specifically, key modifications to a commercially available instrument are described, and the relevant sources of noise from electronic components are outlined. Transient laser-induced thermal effects such as thermal lenses and temperature-dependent shifts in solvent absorption bands can also interfere with the detection of a given signal, and these complications are likewise described. The significance of these issues is apparent when monitoring oxygen’s a→b transition in D2O, a scenario in which the present detection limits of this technique are embodied. Much of the information in this report transcends the specific problem of singlet oxygen detection, however, and addresses issues general to the use of a step-scan FT spectrometer for time-resolved IR measurements. © 2002 American Institute of Physics.
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07.57.Ty Infrared spectrometers, auxiliary equipment, and techniques
07.57.-c Infrared, submillimeter wave, microwave and radiowave instruments and equipment
07.60.-j Optical instruments and equipment
82.50.-m Photochemistry

Development of a hand-held forensic-lidar for standoff detection of chemicals

Grant Thomson and David Batchelder

Rev. Sci. Instrum. 73, 4326 (2002); http://dx.doi.org/10.1063/1.1516832 (3 pages) | Cited 3 times

Online Publication Date: 21 November 2002

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The design of a forensic-lidar is reported, enabling a single operator to perform the spectral identification of a labeled object at 5 m distance using a compact, hand-held instrument, low-power excitation (1 mW) and short sampling times (under 2 s) from a sample less than 100-μm thick. The system integrates a modified single-lens-reflex (SLR) telephoto camera with an optical-fiber coupled Raman probe head. Spectral analysis was achieved using an optical-fiber coupled spectrograph employing a volume-phase holographic grating, charge coupled device array detection and visible excitation. Thus, spectra may be acquired from objects encased in transparent packaging or behind glass windows. The use of a modified SLR camera enables accurate sample alignment using the visible spectrum and collection of surface-enhanced resonance Raman scattered flux through the SLR camera lens using epi-illumination. A single operator may acquire fingerprint recognition of a material using a single hand-held unit and spectrum-matching software. The instrument design is reported with preliminary performance such as spectrograph resolution and transmission. A preliminary spectrum is presented at a standoff distance of 5 m. © 2002 American Institute of Physics.
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82.80.Gk Analytical methods involving vibrational spectroscopy
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
42.68.Kh Effects of air pollution
42.79.Qx Range finders, remote sensing devices; laser Doppler velocimeters, SAR, and LIDAR
07.57.Ty Infrared spectrometers, auxiliary equipment, and techniques
07.68.+m Photography, photographic instruments; xerography
42.40.My Applications
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
42.79.Pw Imaging detectors and sensors
85.60.Gz Photodetectors (including infrared and CCD detectors)
back to top BIOLOGY and MEDICINE

A combined confocal and magnetic resonance microscope for biological studies

Paul D. Majors, Kevin R. Minard, Eric J. Ackerman, Gary R. Holtom, Derek F. Hopkins, Christopher I. Parkinson, Thomas J. Weber, and Robert A. Wind

Rev. Sci. Instrum. 73, 4329 (2002); http://dx.doi.org/10.1063/1.1517146 (10 pages) | Cited 10 times

Online Publication Date: 21 November 2002

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Complementary data acquired with different microscopy techniques provide a basis for establishing a more comprehensive understanding of cell function in health and disease, particularly when results acquired with different methodologies can be correlated in time and space. In this article, a novel microscope is described for studying live cells simultaneously with both confocal scanning laser fluorescence optical microscopy and magnetic resonance microscopy. The various design considerations necessary for integrating these two complementary techniques are discussed, the layout and specifications of the instrument are given, and examples of confocal and magnetic resonance images of large frog cells and model tumor spheroids obtained with the compound microscope are presented. © 2002 American Institute of Physics.
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87.64.mk Confocal
07.60.Pb Conventional optical microscopes
07.57.Pt Submillimeter wave, microwave and radiowave spectrometers; magnetic resonance spectrometers, auxiliary equipment, and techniques
87.64.K- Spectroscopy
87.17.-d Cell processes

Novel resonant-frequency sensor to detect the kinetics of protein adsorption

Alison J. Clark, Lorne A. Whitehead, Charles A. Haynes, and Andrzej Kotlicki

Rev. Sci. Instrum. 73, 4339 (2002); http://dx.doi.org/10.1063/1.1520731 (8 pages) | Cited 1 time

Online Publication Date: 21 November 2002

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Proteins prefer interfaces, and in aqueous solutions they rapidly adsorb to available solid–liquid interfaces. The adsorption process often involves a change in protein conformation at the surface that can result in functional inactivation of the protein. These changes in protein conformation, which are thought to lead to the formation of an entangled gel-like layer of denatured protein, are responsible for a number of deliterious processes, including biofouling on contact lenses and medical implants. The adsorption process is generally irreversible; dilution of protein in the solution phase does not result in protein desorption from the solid. Presumably, this is due to the effects of the protein denaturation and entanglement process on the rate constant for desorption. Nonspecific protein adsorption to solid–liquid interfaces is, therefore, a kinetically controlled process. Hence, measuring and understanding the kinetics of protein adsorption to solid surfaces, including the kinetics of protein conformational changes, is of considerable interest. We have developed a sensor that responds to protein adsorption kinetics and also, we believe, is sensitive to protein conformational changes during adsorption. The device is operated by monitoring the change in resonant frequency of an elastomeric film (25 μm thick), as an aqueous protein solution is exposed to the surface. Since the mass of a monolayer of the protein or other adsorbent is an extremely small fraction of the mass of the film, the observed change in resonant frequency is due almost entirely to changes in the surface tension of the film. Upon exposing the elastomeric film to a protein solution, we observe a continuing change in resonant frequency for more than 24 h, which is well beyond the time it would take for the population of proteins on the surface to equilibrate under diffusion-limited kinetics. This prolonged response is likely due to the surface energy changes of the sensor as the adsorbed protein molecules change their conformation. We present a description of the basic operation of this sensor as well as some examples of its response to bulk protein and surfactant concentrations. © 2002 American Institute of Physics.
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87.15.R- Reactions and kinetics
87.14.E- Proteins
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
87.80.-y Biophysical techniques (research methods)
back to top ELECTRONICS; ELECTROMAGNETIC TECHNOLOGY; MICROWAVES

Low-noise and fast-locking phase-locked loop

S. M. Shahruz

Rev. Sci. Instrum. 73, 4347 (2002); http://dx.doi.org/10.1063/1.1519935 (7 pages)

Online Publication Date: 21 November 2002

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In this article, a phase-locked loop (PLL) is introduced. The proposed PLL, denoted by NPLL, is similar to the standard PLL except that it incorporates a nonlinear element and a low-pass filter in its loop. It is shown that by appropriate choices of these two components, the NPLL outperforms the standard PLL in three respects: (i) it has a large acquisition range, i.e., it can achieve locking in situations where the standard PLL cannot; (ii) it achieves locking fast; and (iii) it has low noise in its output phase. The role of the nonlinear element in enhancing the locking capabilities and noise characteristics of the NPLL is carefully examined. Many tests, results of three of which are reported in this article, show the superior performance of the NPLL. © 2002 American Institute of Physics.
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84.30.Qi Modulators and demodulators; discriminators, comparators, mixers, limiters, and compressors

A programmable log-linear amplifier for wide range nuclear power measuring channels

M. Tahir Khaleeq, Mahmood Alam, and Iftikhar Ahmad Ghumman

Rev. Sci. Instrum. 73, 4354 (2002); http://dx.doi.org/10.1063/1.1518144 (4 pages) | Cited 1 time

Online Publication Date: 21 November 2002

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A programmable log-linear amplifier has been developed for nuclear channels. The amplifier can be programmed for logarithmic, linear or log-linear mode of operation. In the log-linear mode, the amplifier operates partially in log mode and automatically switches to linear mode at any preset point. The log-linear mode is used for wide range operation of nuclear channels and, hence, the amplifier will improve the fault finding capabilities of the nuclear channels used in power range. The amplifier is tested at nuclear reactor and the results are found in very good agreement with the designed specifications. This article presents design and construction of the amplifier and field test results. © 2002 American Institute of Physics.
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28.41.Rc Instrumentation
84.30.Le Amplifiers

Carbon velvet field-emission cathode

D. Shiffler, M. Ruebush, M. Haworth, R. Umstattd, M. LaCour, K. Golby, D. Zagar, and T. Knowles

Rev. Sci. Instrum. 73, 4358 (2002); http://dx.doi.org/10.1063/1.1516853 (5 pages) | Cited 31 times

Online Publication Date: 21 November 2002

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Explosive field emission cathodes comprise an important class of cathodes for high power microwave tubes, having the advantages of light weight as well as requiring no heater for electron emission. Generally, however, this class of cathodes suffers from large amounts of outgassing, nonuniform emission, and very high emittance. This article describes a new class of carbon velvet cathodes that have been coated with a cesium iodide (CsI) salt. We discuss two manifestations of the cathode. We review the lifetime and operation of the cathodes with two different pulse durations, as well as the outgassing from the cathodes during operation. Lifetimes in excess of 980 000 pulses have been obtained, with an outgassing rate of 3.5 atoms per electron. Finally, we discuss the uniformity and emittance of tufted carbon cathodes that have been coated with CsI salt. For comparison, we relate these results to those previously obtained from other cathodes in this class. The cathodes have an emittance of 2.5π mm rad, as compared to the theoretical value, based on computation, of 2.3π mm rad. These new cathodes differ greatly from cathodes such as polymer velvet and tufted carbon fiber cathodes in that no volatiles reside on the cathode and in that a unique coating technique allows the cathodes to function. This new class of cathodes offers a potential replacement for existing thermal cathodes, in that no heater is required for superior operation with low outgassing and long lifetime. © 2002 American Institute of Physics.
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85.45.Db Field emitters and arrays, cold electron emitters
back to top THERMOMETRY; THERMAL DIFFUSIVITY; ACOUSTIC; PHOTOTHERMAL and PHOTOACOUSTIC

Constant voltage anemometer operated hot wire at subsonic speeds over wide overheats in unsteady flows

Guido E. Truzzi, Garimella R. Sarma, and Ndaona Chokani

Rev. Sci. Instrum. 73, 4363 (2002); http://dx.doi.org/10.1063/1.1516850 (6 pages) | Cited 3 times

Online Publication Date: 21 November 2002

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The constant voltage anemometer (CVA) was used to calibrate a hot wire over a wide overheat range. Instead of the output voltage (E) of the anemometer which is normally used, at each test point a quantity represented by “pdr” equal to the ratio of power dissipated in the hot wire (Pw) and the associated difference in the heated resistance of the hot wire (Rw) and its resistance (Ra) at the ambient fluid temperature is calculated. It is shown that the calibration curves so obtained with pdr = Pw/(Rw−Ra) as the output variable instead of E can be represented by a single calibration equation covering the wide overheat range. Overheat variation is equivalent to allowing an ambient temperature change of the fluid at a given setting. It demonstrates that this approach can be used to cover measurements using the hot wire with fluid temperature drifts without using a second hot wire for temperature corrections and without any temperature calibration. The calibration data was then applied to measure the unsteady flow in the near orifice region of synthetic jets with very good results. The measurements confirm the computational predictions that show that although there is flow reversal, over a cycle of oscillation, the synthetic jet actuator spends most of the cycle ejecting rather than ingesting fluid. © 2002 American Institute of Physics.
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47.80.-v Instrumentation and measurement methods in fluid dynamics
47.27.wg Turbulent jets
47.40.Dc General subsonic flows
back to top GENERAL INSTRUMENTS

Simple fiber optic coupled luminescence cryostat

G. D. Meyer, T. P. Ortiz, A. L. Costello, J. A. Brozik, and J. W. Kenney

Rev. Sci. Instrum. 73, 4369 (2002); http://dx.doi.org/10.1063/1.1520730 (6 pages)

Online Publication Date: 21 November 2002

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An easy to fabricate, easy to operate, miniature liquid helium insert cryostat has been designed for variable low-temperature luminescence investigations in the 2.7–77 K region with minimal liquid helium consumption. The cryostat, which can be used inside of a standard liquid helium storage Dewar, is optically coupled both to the luminescence spectrophotometer and to the chosen luminescence excitation source (laser or conventional) by a single 1 mm fused silica fiber optic cable. This extremely simple and compact optical system is designed to give highly reproducible luminescence excitation and collection efficiencies for quantitative luminescence intensity studies. Temperature control in the cryostat is achieved through the dynamic balance of up to three distinct heating/cooling processes: raising or lowering the cryostat with respect to the liquid helium level in the Dewar, heating the cryostat with a small resistance heater, or pumping on the cryostat for sub-4.2 K temperatures. The cryostat can operate effectively throughout the 2.7–77 K range in liquid helium storage Dewars containing less than a liter of liquid helium. The wide range of spectroscopic experiments that this novel optical cryostat design can support is illustrated by a temperature-dependent zero field splitting luminescence lifetime study of Ru(bpy)3Cl2, a temperature-dependent relative luminescence intensity (quantum yield) study of Ru(bpy)3Cl2, and a temperature-dependent luminescence vibronic fine structure study of Ti(Cp)2(NCS)2. © 2002 American Institute of Physics.
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07.20.Mc Cryogenics; refrigerators, low-temperature detectors, and other low-temperature equipment
07.60.Dq Photometers, radiometers, and colorimeters
78.55.Kz Solid organic materials
63.20.-e Phonons in crystal lattices

Time domain characterization of oscillating sensors: Application of frequency counting to resonance frequency determination

Kefeng Zeng, Keat G. Ong, Casey Mungle, and Craig A. Grimes

Rev. Sci. Instrum. 73, 4375 (2002); http://dx.doi.org/10.1063/1.1518128 (6 pages) | Cited 19 times

Online Publication Date: 21 November 2002

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A frequency counting technique is described for determining the resonance frequency of a transiently excited sensor; the technique is applicable to any sensor platform where the characteristic resonance frequency is the parameter of interest. The sensor is interrogated by a pulse-like excitation signal, and the resonance frequency of the sensor subsequently determined by counting the number of oscillations per time during sensor ring-down. A repetitive time domain interrogation technique is implemented to overcome the effects of sensor damping, such as that associated with mass loading, which reduces the duration of the sensor ring-down and hence the measurement resolution. The microcontroller based, transient frequency counting technique is detailed with application to the monitoring of magnetoelastic sensors [C. A. Grimes, D. Kouzoudis, and C. Mungle, Rev. Sci. Instrum. 71, 3822 (2000)], with a measurement resolution of 0.001% achieved in approximately 40 ms. © 2002 American Institute of Physics.
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07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
85.70.Ec Magnetostrictive, magnetoacoustic, and magnetostatic devices
06.30.Ft Time and frequency

A video tracking system for measuring the position and body deformation of a swimming fish

Hao Wang, Lijiang Zeng, and Chunyong Yin

Rev. Sci. Instrum. 73, 4381 (2002); http://dx.doi.org/10.1063/1.1518143 (4 pages) | Cited 1 time

Online Publication Date: 21 November 2002

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A video tracking system based on fringe tracking and camera tracking is developed to simultaneously measure the spatial position and the body deformation of a swimming fish. The control module of the system consists of a fringe pattern tracking system including one tracking mirror and a fringe pattern projector, and a video tracking system including another tracking mirror and a high-speed camera. In the control module, a target trajectory prediction algorithm is used to predict the position of a swimming fish. The two mirrors mounted on two step motors are used to track a swimming fish. The rotation angles of the tracking mirrors are recorded simultaneously. Body position and deformation are calculated from the distorted fringes based on triangulation. The relative accuracy on the body deformation is below 1%. We successfully apply the system to a swimming fish. © 2002 American Institute of Physics.
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87.19.rs Movement
87.19.ru Locomotion
06.30.Bp Spatial dimensions (e.g., position, lengths, volume, angles, and displacements)
87.80.-y Biophysical techniques (research methods)

Micromachined droplet ejector arrays

Gökhan Perçin, Göksenin G. Yaralioglu, and Butrus T. Khuri-Yakub

Rev. Sci. Instrum. 73, 4385 (2002); http://dx.doi.org/10.1063/1.1517145 (5 pages) | Cited 5 times

Online Publication Date: 21 November 2002

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In this article we present a micromachined flextensional droplet ejector array used to eject liquids. By placing a fluid behind one face of a vibrating circular plate that has an orifice at its center, we achieve continuous ejection of the fluid. We present results of ejection of water and isopropanol. The ejector is harmless to sensitive fluids and can be used to eject fuels, organic polymers, photoresists, low-k dielectrics, adhesives, and chemical and biological samples. Micromachined two-dimensional array flextensional droplet ejectors were realized using planar silicon micromachining techniques. Typical resonant frequency of the micromachined device ranges from 400 kHz to 4.5 MHz. The ejections of water through a 4 μm diameter orifice at 3.45 MHz and a 10 μm diameter orifice at 2.15 MHz were demonstrated by using the developed micromachined two-dimensional array ejectors. © 2002 American Institute of Physics.
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85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
47.85.Np Fluidics
07.10.Cm Micromechanical devices and systems
47.55.D- Drops and bubbles
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Nonscanning Brillouin spectroscopy applied to solid materials

Jae-Hyeon Ko and Seiji Kojima

Rev. Sci. Instrum. 73, 4390 (2002); http://dx.doi.org/10.1063/1.1516847 (3 pages) | Cited 8 times

Online Publication Date: 21 November 2002

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We report the first observation of Brillouin spectra of solid samples by using a nonscanning one-pass Fabry-Perot interferometer with a high finesse of 80. Obtained acoustic parameters of a quartz glass are in good agreement with those measured by a conventional scanning multipass Fabry-Perot interferometer. The acquisition time of the present nonscanning interferometer for measuring one meaningful Brillouin spectrum is remarkably reduced in comparison with the scanning one. It has been demonstrated that the present spectrometer is a very powerful tool in the real-time monitoring of transient acoustic properties of condensed matters, like changes in the sound velocity and the damping factor during liquid-glass transitions. © 2002 American Institute of Physics.
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07.60.Ly Interferometers
78.35.+c Brillouin and Rayleigh scattering; other light scattering
62.65.+k Acoustical properties of solids
43.58.-e Acoustical measurements and instrumentation

Vacuum and cryogenic station for microelectromechanical systems probing and testing

B. Legrand, E. Quévy, B. Stefanelli, D. Collard, and L. Buchaillot

Rev. Sci. Instrum. 73, 4393 (2002); http://dx.doi.org/10.1063/1.1518140 (3 pages) | Cited 1 time

Online Publication Date: 21 November 2002

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We have developed a flexible station for probing and testing microelectromechanical systems (MEMS) and relative integrated circuits. The system allows testing devices under vacuum condition ranging from 10−6 to 760 Torr and at variable temperatures from −100 to +150 °C. Electrical measurements up to 3 GHz and optical measurements through glass windows can be performed simultaneously on MEMS devices. Either packaged devices mounted on printed circuit boards or diced or undiced chips are acceptable. Chips are probed using manual probe heads or probe cards. If needed, two separable parts of a MEMS device, for example, an electromechanical part and an electronic integrated circuit, can be tested simultaneously in different temperature conditions. The setup has been successfully used to characterize electromechanical resonators which exhibit quality factors close to 100 000 in high vacuum. © 2002 American Institute of Physics.
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85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
07.20.Mc Cryogenics; refrigerators, low-temperature detectors, and other low-temperature equipment
07.30.Kf Vacuum chambers, auxiliary apparatus, and materials
06.60.Mr Testing and inspecting procedures

Correcting off-axis effects in an on-chip resistive-pulse analyzer

O. A. Saleh and L. L. Sohn

Rev. Sci. Instrum. 73, 4396 (2002); http://dx.doi.org/10.1063/1.1519932 (3 pages) | Cited 4 times

Online Publication Date: 21 November 2002

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A resistive-pulse analyzer is a device that utilizes measurements of the electrical resistance of a solution-filled pore to determine the size of particles that pass through the pore. The relation between particle size and changes in the pore’s resistance is complicated by particles that travel off the central axis of the pore. Here, we present data taken using a microfabricated pore and latex colloids that illustrates the effects of off-axis particles, and propose an algorithm for removing those effects from the data. We show that the ability to remove off-axis effects increases the precision of devices that transport particles through the pore with a pressure-driven flow relative to those that use electrophoretic flow. © 2002 American Institute of Physics.
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82.45.-h Electrochemistry and electrophoresis
82.70.Dd Colloids
06.30.Bp Spatial dimensions (e.g., position, lengths, volume, angles, and displacements)
84.30.Sk Pulse and digital circuits

Current-heating formation of small holes in thin gold or silver films

Nestor Perea-López, Nikifor Rakov, and Mufei Xiao

Rev. Sci. Instrum. 73, 4399 (2002); http://dx.doi.org/10.1063/1.1520727 (3 pages) | Cited 4 times

Online Publication Date: 21 November 2002

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We describe a process to form small holes in thin gold or silver films. The prepared films are useful for optical studies on surface plasmon induced transmission as well as some related phenomena. © 2002 American Institute of Physics.
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78.66.Bz Metals and metallic alloys
81.16.Nd Micro- and nanolithography
81.20.-n Methods of materials synthesis and materials processing
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)

Low-cost mechanical shutter for light beams

Kilian Singer, Selim Jochim, Marcel Mudrich, Allard Mosk, and Matthias Weidemüller

Rev. Sci. Instrum. 73, 4402 (2002); http://dx.doi.org/10.1063/1.1520728 (3 pages) | Cited 6 times

Online Publication Date: 21 November 2002

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Show Abstract
We present a simple design of a fast mechanical shutter for light beams using a low-cost personal computer loudspeaker. The shutter is capable of closing an aperture of 5 mm at a maximum speed of 1.7 mm/ms with a timing jitter of less than 10 μs. When combined with polarization optics, our device can also be used as an alterable switch and adjustable attenuator. © 2002 American Institute of Physics.
Show PACS
42.79.-e Optical elements, devices, and systems
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
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