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In HD Piezoresponse Force Microscopy mode (HD PFM) an AC voltage is applied to the conductive AFM cantilever when the tip comes in contact with the sample during each fast force spectroscopy cycle. Applied AC voltage causes mechanical oscillations of the piezoelectric (ferroelectric) sample.Corresponding vertical and lateral motions of the AFM tip are recorded and processed to get the amplitude and phase characterizing the local piezoelectric coefficient and local polarization direction respectively. Since the AFM tip retracts from the surface in each scanning point, the lateral tipsample interaction force is significantly reduced in comparison to the conventional contact PFM technique. This provides new capabilities for piezoresponse studies of soft, loose and fragile objects like biological samples, nanoparticles etc. Furthermore an AFM cantilever of higher stiffness and resonance frequency can be used.

Electrical characterization of objects, that are weakly attached to the surface, has always been a challenge when using standard AFM modes like Conductive AFM. This was because often the tip moved or abraded the objects of interest. HybriD Mode drastically decreased the impact of lateral forces and simplified these experiments. Comparison of conductive and mechanical maps shown in this example allows the clear identification of single nanotubes and bundles. New stateoftheart HybriD 2.0 control electronics allows simultaneous resonant electrostatic studies using twopass technique Kelvin Probe Force Microscopy Electrostatic Force Microscopy Scanning Capacitance Force Microscopy

Thermoelectric studies of nanoscale structures like np junctions, conductive nanowires, graphene oxide etc. are currently of a great interest. HD Scanning Thermoelectric Microscopy (HD SThEM) allows nondestructive mapping of Seebeck coefficient with tip radiuslimited spatial resolution. HD SThEM working principle is based on direct measurement of generated voltage when conductive tip and sample under different temperatures contact each other during fast force spectroscopy measurements.

Tip Enhanced Raman Scattering (TERS, nanoRaman) is the technique for enhancement of weak Raman signals and for superresolution Raman imaging with spatial resolution less than 10 nm. As a result of comprehensive research performed together with NTMDT SI customers and partners, we are now able to offer to AFMRaman customers mass produced reproducible TERS probes. TERS imaging requires prolonged tipsample contact at each scanning point but Contact AFM is destructive for both the tip and the sample. Thereby, HD mode is a superior technique for cantilevertype TERS since it noticably increases the tip lifetime and makes possible TERS imaging of soft, loose and fragile samples. Thanks to highspeed HybriD 2.0 Control Electronics the approach and withdrawal optical response signal curve (PMT) can be recorded and processed in realtime. This allows to separate the nearfield from farfield component of optical response and to map it with spatial resolution limited by the tip radius.

Tip Enhanced Raman Scattering (TERS, nanoRaman) is the technique for enhancement of weak Raman signals and for superresolution Raman imaging with spatial resolution less than 10 nm. As a result of comprehensive research performed together with NTMDT SI customers and partners, we are now able to offer to AFMRaman customers mass produced reproducible TERS probes. TERS imaging requires prolonged tipsample contact at each scanning point but Contact AFM is destructive for both the tip and the sample. Thereby, HD mode is a superior technique for cantilevertype TERS since it noticably increases the tip lifetime and makes possible TERS imaging of soft, loose and fragile samples. Vacuum measurements in amplitude modulation (AM) mode requires unacceptably low scanning speeds because of extremely high Qfactor of AFM probes. Being a nonresonant mode, HD mode allows at least 10 times faster imaging speed.

HD Scanning Thermal Microscopy (HD SThM) allows studying local thermal properties simultaneously with QNM measurements. From the hardware point of view it was implemented using AppNano VertiSense™ thermocouple probes. The thermal conductivity and temperature mapping modes (CMM, TMM) can be realized by positioning the AFM laser at the end or the central part of the probe, respectively. HD mode working principle allows exceptional spatial resolution of SThM measurements in comparison to conventional Amplitude Modulation (AM) mode. That was demonstrated in TMM of a microheater sample. SThM and HybriD mode is the winning combination for distinguishing between the constituents of polymer blends as demonstrated in the example of a blend of polystyrene (PS) with low density polyethylene (LDPE) (see below). The difference in thermal conductivity of the polymers (PS – 0.12 W/mK; LDPE – 0.33 W/mK) allows the assignment of the colder matrix to LDPE and the hotter islands to PS.

Stateoftheart HybriD 2.0 Control Electronics incorporates highspeed digital lockin amplifiers (LIA) and phase locked loop detector (PLL) for advanced oscillatory resonance modes Amplitude Modulation with Frequency Imaging (AMFI) and Frequency Modulation (FM) modes. They provide exceptional level of spatial resolution of challenging flat and soft samples (selfassembled molecular structures etc.) thanks to ultraprecise control of the tipsample interaction force. Additionally they allow mapping of its mechanical properties. The two images below show topography and probe resonant frequency distribution over lamellar arrangement of short alkane C36H74 on graphite with a spacing of 4.5 nm. One can also see a couple of adsorbates formed on the lamellar surface by disordered alkane chains which are rarely observed by the traditional AM mode.

The new digital controller PX Ultra turns your routine SPM device into easytouse instrument for scientific breakthroughs and advanced research The controller has 5 lockins amplifiers for uponelevel multitechnique leading edge measurements. The up to 5 MHz bandwidth for use of HF cantilevers and high harmonic oscillations’ action for the advanced investigation of electrical and mechanical properties at nanoscale. Lownoise piezoscanner control affords carrying out research by the same scanning element in the range from nanometers to tens and hundreds of micrometers.Ease of upgrade and functional extension of controller due to convenient slot organization. Regularly updated software. LabView compatibility for users’ custom applications. HybriD Mode™compatible.Fully automated adjustment for defined measuring mode. Digital and analogue peripheral ports. Ask online support service.

Operating a scanning probe microscope, where the tipsample force interactions are measured with high precision and at small scales, requires an environment that is free of the external perturbations caused by vibrational and acoustic noise. Just as important is the temperature stability of the microscope in order to ensure a low thermal drift of a sample during experiments. A unique feature of Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM) is a relatively slow feedback mechanism in most of their modes. Therefore, a large number of experiments such as imaging at the atomicscale, profiling of corrugated surfaces, collecting of local force curves in the force volume operation, among others will benefit from lowthermal drift conditions. A stable position of the sample will also help to examine the same surface region with different AFM modes, making the surface analysis more comprehensive.