Focus on Microscopy Faster, Smaller, More Economical Imaging Tools at SPIE 2007: the Effect of Nanotech by Barbara Foster
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Volume 39, Number 20 Focus on Microscopy Faster, Smaller, More Economical Imaging Tools at SPIE 2007: The Effect of Nanotech by Barbara Foster Nanotechnology is having a big effect highlights some of the new technolo- trum from 280 to 720 nm, and provides on imaging equipment. In semiconduc- gies on display during the SPIE exhibit a 20,000-fold light boost. Fast image tor parlance, it is driving a strong “lab to that embody this trend. collection is only part of the story, how- fab” transition: Equipment once found ever. The second half is the challenge of only in the research and development Cameras lead the way, from transferring a quarter of a megabyte of laboratory is now finding its way into data that is being collected 2000 times production. While the more sophisti- 60 to 2000 fps per second. Photron’s solution is 2.6 GB cated laboratory versions retain their Collecting low-light-level images at high of onboard recording memory, enabling role for high precision and applicability speed has long been a challenge for cam- a recording time of 8.2 sec for 1000 fps. to multiple applications, the production era manufacturers. Historically, shutters versions are becoming faster, smaller, on the cameras have been left open to sleeker, and more economical. collect images from dim samples over a New ways to image surface period of time and integrate the result- texture, profi les, and This trend was highly visible at the ing data. By its very nature, however, recent International Society for Opti- this process is slow, and longer integra- roughness cal Engineering (SPIE) meeting, held tion times also result in the collection In the crowded and surging field of August 26–30, 2007, in San Diego, of more stray light and electronic noise. atomic force microscopy (AFM), Veeco CA. SPIE is an interdisciplinary soci- Two companies exhibiting at SPIE have (Woodbury, NY) is still the recognized ety dedicated to the science and appli- solved this historical challenge. leader. Built initially on the 1998 acqui- cations of light, and this particular sition of Digital Instruments , Veeco meeting focused on new ways of inves- Figure 1a illustrates an uncompli- later expanded its SPM group to include tigating nanotechnology. This article cated setup for a Miro camera (Vision technologies from Park Scientific and Research, Wayne NJ) as it might work Topometrix through the subsequent in a production environment. Figure1b acquisition of ThermoMicroscope. a shows the highly magnified image Veeco retained all three engineering of the electronic circuit board being groups and, until recently, three engi- imaged. The circuit board is rotating neering philosophies. At SPIE, Veeco at 7200 revolutions per minute, yet applications scientist Dr. Thomas Müller the image is clear. Also, the camera is pointed out that the company has now located at a much greater distance than combined these three groups. He cited the would historically be expected new Innova SPM as the fi rst instrument b for this level of magnifi cation. to emerge from newly combined efforts. These cameras can also oper- This SPM was specifi cally designed to be ate in dim lighting, despite more affordable and easier to use, while their fast acquisition times. still offering a full range of AFM and STM (scanning tunneling microscopy) The new FocusScope SV200-i techniques including magnetic force, (Photron, San Diego, CA) electrostatic, conductive, thermal, volt- features the ability to acquire age imaging, and nanolithography. rapidly, even at low light lev- els. It mates the newest in AFMs operate much like a phono- complementary metal oxide graph needle, hovering above or hop- semiconductor (CMOS) imag- ping across the surface being imaged. ing sensors with a Generation Clearly, electronic noise is a disruptive III image intensifi er to produce factor. Until recently, many SPM com- a camera capable of collecting panies vacillated between two engi- Figure 1 The Miro camera provides long working 512 × 512 pixel images up to neering approaches: open-loop (non- distances at high magnifi cation coupled with fast action. a) 2000 frames per second, even feedback) systems, which provide lower Camera setup illustrating long working distance; b) image under low-light-level condi- noise thresholds, or closed-loop systems, of parts taken at that distance, rotating at 7200 rpm. tions. The intensifier works which provide greater control of the (Image courtesy of Vision Research.) well over the full visual spec- AFM probe. The Innova features a high- 20 NOVEMBER/DECEMBER 2007 • AMERICAN LABORATORY AAL.pg20-23.Foster.LO.inddL.pg20-23.Foster.LO.indd 1 111/15/071/15/07 111:22:211:22:21 AAMM Volume 39, Number 20 FOCUS ON MICROSCOPY continued planes. Proprietary algorithms then LM gets a nanoboost in thin convert the differences in intensity between the planes into phase infor- fi lm measurement and mation. The resulting data can be imaging nanotubes used to create 3-D images, 2-D pro- Whenever technology moves into a files, step height, waviness parame- new realm, someone announces that ters, and a wide variety of roughness light microscopy is dead, and the move characteristics including Rz, Rq, Rsk, to nanotechnology was no different. Rku, Rv, and Rt. Like the SWLIs, it Nano-Lane (distributed in the U.S. can be used to characterize and image through Micro Photonics, Irvine, CA) Figure 2 Mini Ram, a portable Raman system, MEMS, the topography of electric has announced a new substrate to take will soon be available as an accessory for light micro- circuits, and fracture versus smooth LM into this next technology revo- scopes. (Image courtesy of B&W Tek.) metal or ceramic finishes. Because lution. Sounding like something from the images are collected rapidly, the a Dr. Seuss story, their Sarfus Surfs are system is less sensitive to vibration. contrast-enhancing supports onto which resolution, closed-loop scan that provides PhaseView is available in a standalone samples are deposited. Precise control of one-step zoom without distortion and version as well as a module that can be the deposited layers on the Surf substrate exceptionally low noise. As an added added to an existing light microscope via produces unique control of the refl ection feature, the closed-loop function can be the conventional C-mount camera port. properties of polarized light impinging deactivated dynamically, even during a on the Surf. The result is increased axial scan. It has also been designed to provide sensitivity by a factor of 100. fast and easy tip and sample exchange The microscopy/ and is fi tted with top-down optics with spectroscopy Figure 3 illustrates the ability of a Surf to electronic zoom to locate tip position enhance contrast and resolution. Figure with respect to the sample. Its new SPM- convergence continues 3a shows the image of double-walled car- lab software allows data from partially Integrating AFM with Raman acquired images to be analyzed on the fl y spectroscopy has been a major a at any time during the acquisition process trend over the past several years. without interrupting the scan. B&W Tek (Newark, DE) prom- ises to extend this chemical fi n- Scanning white light interferometry gerprinting capability to light (SWLI) has long been a staple for opti- microscopy (LM) in the near cal profiling, and was well-represented future, using its elegant, por- on the SPIE show fl oor by the two giants table MiniRam system (Figure in the industry (Veeco, selling the Wyko 2). To achieve this small foot- line, and Zygo, Middlefi eld, CT) as well print and economic pricing, the as by more recent entry 4D Technolo- company designed its own low- gies (Tucson, AZ). Veeco has automated cost diode lasers, thermoelectric its NT9100 to form the new NT9800, a cooling, and sensitive CCD sen- major step toward the production line. sor. As shown in Figure 2, there b An internal laser reference, unique to is a slim, onboard computer as the company, provides self- calibration well as USB communication to and compensates for system drift due to a laptop or desktop. The result: a environmental or mechanical instabili- lightweight, portable spectrom- ties. Automated measurement sequences eter with a spectral range from (recipes) are also part of the software, as 175 to 3100 cm–1, at less than well as datalogging and pass–fail criteria one-tenth the cost of a typical for real-time process feedback and sta- laboratory instrument. While tistical process control (SPC). The key large laboratory spectrometers application for the NT9100 is imaging typically have spectral resolu- microelectromechanical devices (MEMs) tion on the order of 0.1 cm–1, the and dynamic MEMs. MiniRam’s spectral resolution is 5 cm–1, very reasonable for less Figure 3 Surf substrates extend light micros- The PhaseView (San Diego, CA) sys- demanding, routine analyses. A copy’s imaging in X, Y, and Z. a) Double-walled tem takes a slightly different approach to slightly larger desktop version carbon nanotubes (50 nm diam). b) When the optical profi ling and represents the new of this system has already been liquid crystal 4-n-octyl-4-cyanobiphenyl (8CB) is category of simpler, less expensive instru- retrofi tted to a confocal micro- deposited on a Surf at its smectic/nematic transitions ments. Comprising a series of projection scope, and B&W is investigat- temperature, the drop spontaneously spreads to form lenses built into a special adapter, it takes ing a similar configuration for steps of regular heights on the order of tens of nano- two or more images at different focal the MiniRam. meters. (Image courtesy of Micro Photonics.) 22 NOVEMBER/DECEMBER 2007 • AMERICAN LABORATORY AAL.pg20-23.Foster.LO.inddL.pg20-23.Foster.LO.indd 2 111/15/071/15/07 111:22:331:22:33 AAMM Volume 39, Number 20 New services help plexes used as nonviral vectors for gene delivery and for accessing the hydropho- laboratories access the bic interior of biological as well as artifi cial microworld and nanoworld membranes.