Conductive AFM Probes

Originally, the first scanning probe technique developed was dealing with conductive probes: Scanning Tunneling Microscopy (STM), a technique where a sharped Tungsten wire tip was scanned across a surface, whilst controlling the tunneling current between STM tip and surface. Honored with the Physics Nobel Prize in 1986, the major drawback was, that Scanning Tunneling Microscopy was limited to conductive surfaces only.

To expand the main STM sample information – topography – from conductive to arbitrary surfaces, Scanning- or Atomic Force Microscopy (AFM) was developed. A bunch of characterization methods were developed for AFM and also the electrical properties of surfaces came into focus.

The standard probes for AFM are either made out of single crystalline Silicon or by depositing a thin Silicon-Nitride film. These materials are either insulating or quickly form an insulating oxide. To obtain electrical information of a sample, AFM probes are usually coated with a conductive material. Various materials are used here, but depending on the application, either Platinum (usually an alloy of 95% Pt and 5% Ir for hardness reasons is used here), Platinum Silicide, Cobalt alloy or Diamond are used.

AFM applications using a conductive AFM probe mainly split up into two fields: Firstly, methods where the AFM probe is in contact with the surface and an electrical current occurs. And secondly, the electrostatic or lift mode techniques.

Conductive AFM (c-AFM) is performed in contact mode. Basically, the conductively coated AFM probe is in contact with the sample surface and a bias voltage is applied between AFM tip and sample. The measured current gives information about the electrical properties of the scanned area. Depending on the method, well defined forces are applied to the AFM tip. Therefore, the conductive coating used for those applications has to show a good resistance against wear

Scanning Capacitance Microscopy (SCM) is used to map the carrier concentrations in semiconductor samples. The principle is, that a Metal-Oxide-Semiconductor (MOS) capacitor structure is formed, where the conductive AFM tip acts as the “metal” part of the capacitor. By applying an overlaying DC and AC voltage, type and quantity of dopant atoms could be analyzed. Normally, an AFM cantilever with a medium stiffness is used here, stiff enough to ensure a stable contact which guarantees a consistent capacitor area. Wear resistant coatings like Diamond or Platinum Silicide are used for SCM applications on any type of AFM cantilever. We recommend CDT-CONTR or PtSi-CONTCDT-FMR or PtSi-FMCDT-NCHR or PtSi-NCH as well as All-In-One-DD AFM probes for Scanning Capacitance Microscopy.

Conductive AFM (c-AFM), Tunneling AFM (TUNA), I-V-Spectroscopy: Simply by applying a bias voltage to an AFM tip or sample the local conductivity or its variations could be observed. The principle of c-AFM and TUNA is identical, c-AFM is the more general description whereas TUNA normally is related to the characterization of insulating layers. In c-AFM usually only a few orders of magnitudes in current are observed, whereas the range of TUNA currents can vary from extremely low tunneling- up to high breakdown currents of insulating layers. Additionally, the characterization of insulating layers could be performed in different ways. Either by applying a constant bias voltage or by ramping the voltage at a fixed place of the scan. This technique is called I-V-Spectroscopy. Again, wear resistant coatings like doped Diamond or Platinum Silicide on various AFM cantilever types, depending on the application, are the choice for c-AFM and TUNA applications.

Scanning Spreading Resistance (SSRM): the second method to obtain information on semiconductor dopants and the position of p-n-junctions is SSRM. In its macroscopic version, 2 needles with defined radii and spacing are pressed through the native oxide into the semiconductor. A defined voltage is applied and the current is being measured. Usually, the surface is beveled in a very shallow angle and therefore, one obtains a high spatial resolution. In SSRM, due to the small radius of an AFM tip no sample preparation (beveling) is needed. Scanning Spreading Resistance is performed on cross-section of samples. To penetrate the native oxide an AFM cantilever with a very high force constant is needed. Only Diamond as a conductive coating is able to withstand the high forces of SSRM. Usually CDT-NCHRDDESP or All-In-One-DD are used for SSRM.

Contrary to c-AFM applications performed in contact with the sample, the so-called Lift Mode techniques are applications where in a first line scan the topography is recorded, and during the retrace in a well-defined height above the sample, the interaction of the electrically charged AFM probe with the charges on the sample are recorded. For these applications medium hard AFM cantilevers are used: stiff enough to ensure a proper AC or Tapping Mode topography imaging and soft enough to detect the changes in the electrical field between AFM tip and sample. As the wear in these modii is low, thin coatings with highly conductive materials as Platinum or Platinum Silicides are used here.

In Electrostatical Force Microscopy (EFM). After imaging the topography in AC or Tapping Mode AFM during one direction of the scan, the AFM tip is lifted up and traced back with a defined height above the surface. Charges on the biased conductively coated AFM probe are interacting via electrostatic forces with charges on the sample. If the charge distribution changes the electric force gradient changes and the AFM cantilever is bent which is detected by the laser deflection.

Kelvin Probe Force Microscopy (KPFM). KPFM works analog to EFM. Additionally, in the lifted scan trace an AC voltage is applied to the AFM tip, generating a capacitive force. Compensating this capacitive force by adding and mapping another DC voltage gives information about the work function of the investigated materials.

For all Lift Mode techniques, Electrostatical Force Microscopy as well as Kelvin Probe Force Microscopy, AFM probes coated with a low resistivity material like Platinum or Platinum Silicide on a medium hard soft tapping or force modulation AFM cantilever are recommended (PtSi-FM, PPP-EFM, EFM, ElectriMulti 75).

81 results matching your criteria
NW-CDT-NCHR

NW-CDT-NCHR

Diamond Coated, Conductive Tapping Mode AFM Probe

Coating: Diamond,Conductive Diamond
Tip Shape: Standard
AFM Cantilever:
F 400 kHz
C 80 N/m
L 125 µm
NW-CDT-NCLR

NW-CDT-NCLR

Diamond Coated, Conductive Tapping Mode AFM Probe with Long Cantilever

Coating: Diamond,Conductive Diamond
Tip Shape: Standard
AFM Cantilever:
F 210 kHz
C 72 N/m
L 225 µm
PPP-NCHPt

PPP-NCHPt

Electrical, Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Standard
AFM Cantilever:
F 330 kHz
C 42 N/m
L 125 µm
ATEC-NCPt

ATEC-NCPt

Electrical, Tapping Mode AFM Probe with REAL Tip Visibility
Coating: Electrically Conductive
Tip Shape: Visible
AFM Cantilever:
F 335 kHz
C 45 N/m
L 160 µm
PPP-NCSTPt

PPP-NCSTPt

Electrical, Soft Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Standard
AFM Cantilever:
F 160 kHz
C 7.4 N/m
L 150 µm
PPP-NCLPt

PPP-NCLPt

Electrical, Tapping Mode AFM Probe with a Long AFM Cantilever
Coating: Electrically Conductive
Tip Shape: Standard
AFM Cantilever:
F 190 kHz
C 48 N/m
L 225 µm
NCHPt

NCHPt

Electrical, Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Standard
AFM Cantilever:
F 320 kHz
C 42 N/m
L 125 µm
ARROW-NCPt

ARROW-NCPt

Electrical, Tapping Mode AFM Probe with Tip at the Very End of the Cantilever
Coating: Electrically Conductive
Tip Shape: Arrow
AFM Cantilever:
F 285 kHz
C 42 N/m
L 160 µm
top value
HQ:DMD-XSC11

HQ:DMD-XSC11

AFM Probe with 4 Different Diamond Coated, Conductive Cantilevers for Various Applications
Coating: Conductive Diamond
Tip Shape: Rotated
AFM Cantilevers: 4
F 18 kHz
C 0.5 N/m
L 500 µm
F 110 kHz
C 6.5 N/m
L 210 µm
F 210 kHz
C 18 N/m
L 150 µm
F 450 kHz
C 95 N/m
L 100 µm
HQ:NSC36/Pt

HQ:NSC36/Pt

AFM Probe with 3 Different Electrical, Force Modulation Mode AFM Cantilevers
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilevers: 3
F 90 kHz
C 1 N/m
L 110 µm
F 130 kHz
C 2 N/m
L 90 µm
F 65 kHz
C 0.6 N/m
L 130 µm
HQ:DPER-XSC11

HQ:DPER-XSC11

AFM Probe with 4 Different Electrical AFM Cantilevers
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilevers: 4
F 15 kHz
C 0.2 N/m
L 500 µm
F 80 kHz
C 2.7 N/m
L 210 µm
F 155 kHz
C 7 N/m
L 150 µm
F 350 kHz
C 42 N/m
L 100 µm
HQ:DPE-XSC11

HQ:DPE-XSC11

AFM Probe with 4 Different Electrical Cantilevers
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilevers: 4
F 15 kHz
C 0.2 N/m
L 500 µm
F 80 kHz
C 2.7 N/m
L 210 µm
F 155 kHz
C 7 N/m
L 150 µm
F 350 kHz
C 42 N/m
L 100 µm
Mix and Match Box

Mix and Match Box

Mixed box: up to 400 MikroMasch AFM probes
Coating: various
Tip Shape: various
HQ:NSC15/Pt

HQ:NSC15/Pt

Electrical, Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilever:
F 325 kHz
C 40 N/m
L 125 µm
ElectriAll-In-One

ElectriAll-In-One

Electrical AFM Probe with 4 Different AFM Cantilevers
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilevers: 4
F 15 kHz
C 0.2 N/m
L 500 µm
F 80 kHz
C 2.7 N/m
L 210 µm
F 150 kHz
C 7.4 N/m
L 150 µm
F 350 kHz
C 40 N/m
L 100 µm
HQ:NSC14/Pt

HQ:NSC14/Pt

Electrical, Soft Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilever:
F 160 kHz
C 5 N/m
L 125 µm
HQ:XSC11/Pt

HQ:XSC11/Pt

AFM Probe with 4 Different Electrical Cantilevers
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilevers: 4
F 15 kHz
C 0.2 N/m
L 500 µm
F 80 kHz
C 2.7 N/m
L 210 µm
F 155 kHz
C 7 N/m
L 150 µm
F 350 kHz
C 42 N/m
L 100 µm
ElectriTap300-G

ElectriTap300-G

Electrical, Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilever:
F 300 kHz
C 40 N/m
L 125 µm
ElectriTap190-G

ElectriTap190-G

Electrical, Tapping Mode AFM Probe with Long AFM Cantilever
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilever:
F 190 kHz
C 48 N/m
L 225 µm
ElectriTap150-G

ElectriTap150-G

Electrical, Soft Tapping Mode AFM Probe
Coating: Electrically Conductive
Tip Shape: Rotated
AFM Cantilever:
F 150 kHz
C 5 N/m
L 125 µm
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