product review
The Saga of AFM A journey into a hot analytical market. Cheryl M. Harris
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COURTESY OF ANTONIO GARCIA
nyone who’s an expert in atomic force microscopy (AFM) knows the business has seen enough transition throughout the years, with companies coming and going like the changing of the seasons. That’s because these remarkable microscopes with widespread application have created a competitive market for buyers in large semiconductor industries, university laboratories, and small analytical testing companies. Don Chernoff, president of Advanced Surface Microscopy, an independent analytical and contract research laboratory in Indianapolis, IN, has seen at least five AFM businesses restructure in five years. “There’ve been a number of companies that have made a small impact in the market and disappeared.” When Analytical Chemistry last reviewed atomic force microscopes in 1996, we listed five example companies: Burleigh Instruments, Inc.; Digital Instruments (DI); Park Scientific Instruments; TopoMetrix; and Veeco Instruments. Today, that same table would have just one company: the DI/Veeco Metrology Group, the result of multiple company mergers. What happened in those five years? Burleigh stopped selling atomic force microscopes; ThermoMicroscopes, now TM Microscopes, bought Park Scientific and TopoMetrix; and Veeco ended up buying TM Microscopes and DI. “Competition is always good,” says Monte Heaton, director of marketing at DI/Veeco. “It makes everybody work harder, and consolidation has some benefits too.” But company representatives also recall the many lawsuits generated
N O V E M B E R 1 , 2 0 0 1 / A N A LY T I C A L C H E M I S T R Y
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product review
Table 1. Selected atomic force microscopes. Product
easyScan
MultiMode
Dimension 3100, 5000, 7000, 9000; Vx series Atomic Force Profilers
Company
Nanosurf Grammetstrasse 14 CH-4410 Liestal, Switzerland 41-61-927-5646
Digital Instruments/Veeco Metrology Group 112 Robin Hill Rd. Santa Barbara, CA 93117 800-873-9750
Digital Instruments/Veeco Metrology Group 112 Robin Hill Rd. Santa Barbara, CA 93117 800-873-9750
URL
www.nanosurf.com or www.rhk-tech.com www.di.com
www.di.com
Approximate price (USD)
$31,000 (basic excluding computer); $41,000 (fully accessorized)
Doesn’t disclose pricing in a public forum
Doesn’t disclose pricing in a public forum
Measurement modes
Contact in air, STM (option)
Contact mode, TappingMode, noncontact, PhaseImaging, MFM, EFM, surface potential imaging, SKPM, force modulation mode, LFM, STM, SthM, LiftMode, force volume mode; also performs in-air and in-liquid operation, nano-identification, nanoscratching, nanotribology, nanolithography; electrochemical AFM, electrochemical STM
Contact mode, TappingMode, noncontact, PhaseImaging, MFM, EFM, surface potential imaging, SKPM, force modulation mode, LFM, STM, SCM, SSRM, Tunneling AFM, C-AFM, SthM, LiftMode, force volume mode; also performs in-air and in-liquid operation, nano-identification, nanoscratching, nanotribology, nanolithography, nanomanipulation (some modes are not supported on automated or semi-automated microscopes)
Up to 100 100
Up to 120 120 (≤0.005)
~ 90 90 (≤0.005) for 3100, 5000, and 9000; ≥ 65 65 (≤0.005) for 9000Metrology and Vx series ~ 6 (≤0.0001) for 3100 and 5000; ~ 6 (0.0001) for 9000; ≥ 6 (0.0003) for Vx series Closed loop or patented non-linear-waveform-applied precalibrated open loop
Scanner resolution x–y (µm) z (µm)
Up to 20 (allows for pits in valley to be scanned) Scan control Calibrated open loop (electromagnetic instead of piezoelectron scanner)
Up to 10 (≤0.0001) Patented nonlinear-waveformapplied precalibrated open loop
Probe travel 13 (with sample stage), otherwise N/A / (mm) / stage >0.5 resolution (µm)
Manual: 2 2 / N/A
Motorized: 125 100 for 3100; 200 200 for 5000, 9000, Vx 210, and Vx 200; 300 300 for 9300, Vx 310, and Vx 300 / 2 for 3100; 1 for 5000; 0.1 for 9000 series
Sample size (mm)
Sample of any size
Up to 30 diameter
3100: up to 150 diameter (up to 200 with optional chuck), or up to thickness of 12; 5000: 200 square with x–y stage, up to 350 in diameter with rotary stage, and up to 12 thickness; 9000 series and Vx Series: up to 300 in diameter and up to 12 thickness
Microscope
Mobile and stand-alone, optional color CCD camera
Optical up to 800 magnification, CCD camera; viewing area changes with magnification
3100 and 5000: optical 410–1845 with 150- to 675-µm viewing area, optical resolution 1.5 µm, color CCD camera, and motorized zoom and focus; 9000 series: optical 410–1845 with 100- to 500-µm viewing area, 6 mm for low-magnification optics, color CCD camera, resolution 1.5 µm, optical image capture capability; Vx series, optical 410–1845 with 150- to 675-µm viewing area, optical image capture capability, color CCD camera
Accessories
Calibration standard, video camera, easyScan Scanning Tunneling microscope head, transparent cover with integrated 10 optics, complete tool set for STM, extra teacher’s manual
Specialized fluid cells and cantilever holders, sample mount for cross sections, STM converters, vibration and acoustic isolation systems; electrochemical AFM and electrochemical STM hardware options with integrated electrochemistry software for voltammetry and cell potential control
Specialized fluid cells and cantilever holders, sample mounts for hard disks and cross sections, nonmagnetic adapters, STM converter, optical image and AFM image-based pattern recognition, vibration and acoustic isolation systems; also available, Navigator (for import and analysis of water defect maps), NanoScript automation software
Special features
Mobile, low-cost, and easy-to-use elec- High-resolution multimode-operation tromagnetic scanner; also available, SPM; upgrade path for new techmotorized automatic sample-to-tip ap- nologies proach, real-time hardware slope compensation, automatic z-offset; atomic force microscope can be operated using a laptop computer to provide atomic resolution on a normal table
3100, 5000: large stage for sample mounting and ease of access, low-noise stages; 9000 series and Vx series: automatic tip exchange available; Vx series: combines profiler and AFM, provides AFM resolution over long scans
MFM: magnetic force microscopy; EFM: electric field microscopy; SKPM: scanning Kelvin probe microscopy; LFM: lateral force microscopy; SthM: scanning thermal microscopy; C-AFM: conductive; SCM: scanning capacitance microscopy; SSRM: scanning spreading resistance microscopy; EC-AFM/EC-STM: electrochemical; LC-STM, low-current; MACMode, magnetic force-driven and intermittent contact; FFM, friction force microscopy 628 A
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product review
Table 1. Selected atomic force microscopes (continued). Product
BioScope
NanoScope
UHV 325 qPlus AFM
Company
Digital Instruments/Veeco Metrology Group 112 Robin Hill Rd. Santa Barbara, CA 93117 800-873-9750
Digital Instruments/Veeco Metrology Group 112 Robin Hill Rd. Santa Barbara, CA 93117 800-873-9750
RHK Technologies, Inc. 1050 E. Maple Rd. Troy, MI 48083 248-577-5426
URL
www.di.com
www.di.com
www.rhk-tech.com
Approximate price (USD)
Doesn’t disclose pricing in a public forum
Doesn’t disclose pricing in a public forum
Doesn’t publicly publish pricing
Measurement modes
Contact mode, TappingMode, noncontact, N/A PhaseImaging, MFM, EFM, surface potential imaging, SKPM, force modulation mode, LFM, STM, LiftMode, force volume mode; also performs in-air and in-liquid operation, nano-identification, nanoscratching, nanotribology
Scanner resolution x–y (µm) ~90 90 (≤0.005) z (µm) ~6 (0.0001 in air; 0.0002 in liquid) Scan control Patented nonlinear-waveform-applied precalibrated open loop Probe travel N/A / N/A (mm) / stage resolution (µm)
Noncontact, STM (vacuum)
N/A 5 5 (0.05 nm) N/A .65 (0.005 nm) Closed loop or patented nonlinear-waveform-applied Precalibrated open loop precalibrated open loop N/A / N/A
6.4 6.4 / .02
N/A
10–16, depending on sample holder
Sample size (mm)
Slides: 25 75 slide or cover slip (standard); petri dishes: 60-diam polystyrene dishes, fluid level may be up to 7 deep
Microscope
AFM replaces the stage of an existing inverted N/A optical microscope
Optical, color CCD camera; also available, heating and cooling options, multicustom stages
Accessories
Specialized fluid cells and cantilever holders, STM converters, vibration and acoustic isolation systems
N/A
Heating: 300–1000K (W-filament, quartz lamp, direct current); cooling: liquid nitrogen (
