Scanning Probe Microscopy Overview

Scanning probe microscopy (SPM) takes on different forms depending on the operating environment (ambient, liquid or vacuum), the type of measurement force under investigation (short-range or long-range), and the actuation scheme (mechanical, electrical, magnetic, or optical). SPM is a well-established high-resolution imaging tool. It features frequently in interdisciplinary projects in the fields of nanotechnology and nano-optics, and can be used to address and manipulate nano-objects such as single atoms, single molecules and quantum dots.

Zurich Instruments focuses on instrumentation challenges in SPM, in particular on those related to new modes of operation, new sensors, or fast real-time data acquisition and feedback loops. With instruments covering frequencies from DC to 600 MHz, Zurich Instruments helps SPM specialists to perform time- and frequency-domain data analysis to capture and control complex tip-sample interactions.

As shown in the table below, each instrument platform comes with options that enable an SPM setup to grow with its user's needs: for example, it is possible to synchronize multiple instruments as experiments grow in complexity.

Zurich Instruments serves the SPM community at large by providing integrated solutions with Scienta Omicron for UHV-SPM systems and with Bruker Anasys Instruments for atomic force microscopy infrared-spectroscopy (AFM-IR), and by offering a simple analog and DIO interface to most third-party microscopes through their respective signal access module (SAM). All data internally generated by the lock-in amplifier and PID loops can be captured in the form of multiple images or a triggered data stream through the Data Acquisition (DAQ) module. Four analog auxiliary outputs are available on all instrument platforms for quick and convenient interfacing to the microscope.

Three reasons to use Zurich Instruments in SPM experiments

• You are free to implement any SPM modes and develop new instrumentation techniques on an existing SPM platform.
• The highest signal-to-noise ratio or demodulation speed is guaranteed while ensuring the optimization of your chosen experimental configuration.
• You can explore your parameter space thanks to a wealth of time- and frequency-domain analysis and data acquisition tools.

Platform	MFLI	HF2LI	UHFLI
Frequency range Sampling rate	DC - 5 MHz 60 MSa/s	DC - 50 MHz 210 MSa/s	DC - 600 MHz 1.8 GSa/s
Best-suited modes	Non-contact AFM, FM-AFM Multi-frequency AFM (up to 4 frequencies or harmonics) Most Kelvin probe force (KPFM) modes with electrical control only STS, differential spectroscopy measurements	Dual-frequency resonance tracking (DFRT) Multi-frequency AFM (up to 6 frequencies or harmonics) All Kelvin probe force (KPFM) modes with mechanical and electrical control Ultrasound microscopy	Big data analysis Band excitation Electrical pump-probe Time-resolved experiments High-speed AFM
Highlights	Highest sensitivity below 5 MHz Threshold Unit (tip protection) Accurate impedance measurement capability	Simultaneous vertical and lateral detection Control of 2 separate actuation schemes Multiple direct sideband analysis	Highest data transfer rate Fastest demodulation speed Arbitrary actuation scheme combined with time-domain analysis
Relevant options for SPM	MF-MD Multi-Demodulator MF-PID Quad PID/PLL Controller MF-MOD AM/FM Modulation MF-IA Impedance Analyzer	HF2LI-PID Quad PID Controller HF2LI-MF Multi-Frequency HF2LI-MOD AM/FM Modulation	UHF-AWG Arbitrary Waveform Generator UHF-DIG Digitizer UHF-BOX Boxcar Averager UHF-PID Quad PID/PLL Controller UHF-MOD AM/FM Modulation
Software and APIs	LabOne® software and Application Programming Interfaces (APIs) for Python, C, MATLAB®, LabVIEW™ and .NET available for all platforms

Browse through our SPM applications pages to read about some of the modes discussed above, and get in touch with us to discuss your application or adaptation requirements. We will be happy to set up remote demonstrations of our instruments in the context of SPM.