Research and development of semiconductor materials and devices requires extensive electrical measurements. One major challenge in this field is the characterisation of electrical properties in varying environments. A number of industry experts reached out to The National Physical Laboratory (NPL) to enquire about the electrical transport properties of their materials, specifically seeking information on electrical resistivity/conductivity, doping type, carrier density and mobility. Being able to understand these parameters in different environmental conditions and temperatures helps companies develop a better understanding of their materials and devices.
We developed electrical testbeds for devices and materials, including characterisation of the electrical transport properties (electrical resistivity, carrier type/mobility/density), in the following conditions:
Ambient
Vacuum (down to 10-5 mbar)
Controlled humidity (0 to 80%)
Temperaturerange of 2 K to 400 K
Large magnetic field (±9 T)
DC or AC excitation (up to 100 kHz)
Our capabilities can be adapted for custom electrical measurements including transistor measurements (output and transfer characteristics, capacitance – voltage measurements), noise-spectral density measurements, using arbitrary waveform (pulses) for excitation, etc.
While some of the measurement requirements we received could make use of established capabilities such as the Hall effect measurements, most of them required different degrees of modifications to existing capabilities. These ranged from simply adding a new way of mounting the sample (for the stretchable films for instance) to designing, implementing, and automating completely new sets of measurements.
NPL helped industry overcome several challenges by providing measurement services through Measurement for Quantum (M4Q) and our Graphene Flagship Validation Service. A number of projects involving measurements of electrical/semiconductor materials helped the companies improve their material preparation and device fabrication processes. Other impacts include demonstration of materials’ and devices’ resilience against varying environmental conditions. Companies used our robust measurement results to make crucial business decisions, helping them to gain further investment into their materials. We enabled companies to confidently compare their products to others and evaluate the potential of their existing products for new applications (lateral markets).
Really useful learning that adds to our corporate knowledge
- Paul Ladislaus, Research and development manager at First Graphene
Absolutely excellent. Very good quality of work
Marco Caffio, CSO, Integrated Graphene