The Tensormeter is designed for automated precision measurements of resistances and related quantities. It uniquely combines DC & AC measurements with an integrated switching matrix.
The RTM2 offers the low noise of lock-in amplifiers,
the 8+ digits of dynamic range of high-end multimeters, and unparalleled stability to study ppb-level effects. Nano-Ohm investigations become easier than ever.
The innovative connector design allows conventional BNC operation with passive shielding or with active guard shielding. This extends the upper impedance limits to the Tera-Ohm range at DC and increases AC bandwidth by about two orders of magnitude for testing Mega-Ohm devices.
The Tensormeter RTM2 enables the automated recording of the complete Resistance Tensor (Rx, Ry, RH) with one single device, even on unpattern thin films.
The RTM2 can be used for materials research, thin film characterization as well as sensor, wafer and device testing. The unique ability for AC tests in quickly-multiplexed settings enables tighter component binning during live production.
Benefits of the switching matrix
Conventional precision devices such as multimeters or lock-in amplifiers rely on the 4-wire resistance measurement method with a static connection to a device under test (DUT). This method unavoidably contaminates the measurement with various parasitic contributions both from the DUT and from the measurement device itself.
Measurement arrangements such as the Wheatstone bridge or lithographic Hall-bar patterning can be used to reduce the impact of some of the parasitics, but they all rely on exact and stable symmetries of real resistors or etch patterns, which is unachievable in practice.
In contrast, a matrix switch allows to segregate the parasitic contributions in the time domain. One example is the van-der-Pauw method that allows the exact discrimination of longitudinal and transverse resistance, even on irregularly shaped samples without a lithographic patterning.
Another example is the “auto-zeroing” employed by some DC meters, in order to compensate offset drift. But it doesn’t stop there. The full matrix switch of the Tensormeter and its full compatibility with tightly-multiplexed AC measurements open astonishing possibilities.
It is possible to compensate both offset and gain drift for unlimited stability. “Unlimited” is literal here: Achievable precision is not 7, 8 or 10 digits; it is however many digits you are willing to wait for. Enter the world of metrology in your own lab.
It is also possible to compensate compound non-linearity of the entire instrumentation. This allows testing for sub-ppm-level I-V-nonlinearity making higher-order transport physics visible at lower and gentler current densities.
Reconfigurable device architecture based on an integrated switching matrix
8 user-defined ports (BNC connectors) with freely determinable function (input, output and/or reference)
BNC shields configurable as passive ground or active guard
Conventional AC and DC 4-wire measurements with fixed connections (Kelvin or Hall geometry)
AC and DC measurements with alternating connections (Tensor measurements, van-der-Pauw or ratiometric measurements)
Simultaneous measurement of exactly separated absolute values for longitudinal and transverse resistances of thin films without lithographic patterning
Software presets for common measurement modes, specification of any user-specific switching sequences
TCP-based communication and easy integration in any environment (e.g. Labview, C, Python)
Replaces all standard devices for electrical characterization measurements
(e.g. Lock-in Amplifier, SMU, DMM)
Overcomes the limitations of stationary 4-point measurements by an integrated Matrix Switch
Offers presets for van-der-Pauw and Resistance Tensor measurements and allows for full user configurability
Makes complex sample preparation unnecessary (e.g. lithographic structuring).
Allows for easy connectivity to many different measurement setups (e.g. probe stations, cryostats, vacuum systems)
Saves measuring time and enhances sample throughput
Applications & Examples
Materials research and characterization
Industrial R&D and wafer/device testing
solid state physics
new functional electronic materials and devices
Typical measurement examples
Ultra-low noise and high stability AC & DC 4-wire measurements in standard geometries (Kelvin and Hall layouts)
Van-der-Pauw switched connection 4-wire measurements on irregular, unstructured thin-film samples
Sub-ppm relative change and non-linearity measurements in fundamental physics and metrology
Zero-Offset Hall 4-wire measurements (exact separation of longitudinal and transverse resistance even with unstructured samples)
Ratiometric resistance measurements to eliminate sample and device drifts
High drive harmonic distortion measurements,
pulse & measure routines
Low resistive samples
Zero-offset Hall: eliminate drift and parasitics
Differential Input Noise Spectrum of a resistive sensor. Ultra-low wideband & 1/f noise AC measurements allow accurate sensor characterization and operation.
Differential Input Noise Spectrum of a Hall measurement on a thin film sample. The Zero-Offset Hall preset of the Tensormeter eliminates thermal drift and allows long integration and orders of magnitude improved sensitivity compared to regular 4-wire Hall measurements.
Loss of magnetization during warmup of an anti-ferromagnetic sample monitored in Hall Resistance. The Zero-Offset Hall preset of the RTM1 (top) clearly shows the loss of signal. On the contrary, parasitic signal contributions overshadow the useful magnetization signal in a regular 4-wire Hall measurement of the same sample (bottom).
Hardware / Installation
Thermodynamics and Exchange Stiffness of Asymmetrically Sandwiched Ultrathin Ferromagnetic Films ...
Yastremsky et al., Phys. Rev. Applied 12, 064038 (2019)