Characterisation

 

We have recently installed a new Physical Property Measurement System (PPMS) from Quantum design (Evercool II). Funded by our ERC consolidator grant.

This system includes a 9T magnet with DC Magnetism, AC Susceptibility, Resistivity, Vibrating Sample Magnetometer etc. We have extended its electronics for Hall effect and device measurements at low temperatures.

This extends our shared departmental dilution refrigerator (BlueFors 7mK) capabilities for low temperature characterisation of our superconducting diamond. As well as these standard options we have multiple custom measurement options built in house.

Quantum design Evercool II PPMS (2K-350K)

BlueFors Dilution refrigerator for 7mK operation

Woolham M2000 Spectroscopic Ellipsometer with variable angle and wafer mapping option

For film film metrology, we currently use Spectroscopic Ellipsometry, Spectral Reflectance and Grazing Incidence Interferometry. For very thin films we use a Woolham M2000 Spectroscopic Ellipsometer which has nm resolution. This system is equipped with a fully automated variable angle wafer mapping stage. This system has a laser focus option for automated focusing in the Z direction which can also be used to characterise wafer bow.

For fast measurements we often use a Filmetrics F20 Spectral Reflectance system which has resolution down to 20 nm.

For general wafer bow observations we use a Logitech GI20 grazing incidence interferometer. The image below shows an example of a flatness measurement of a 2” wafer. The fringes on the screen on the bottom right represent 2µm, thus it is trivial to calculate the wafer bow. This system is predominantly used to monitor wafers whilst compensating for bow with a CMP chuck.

Filmetrics F20 Spectral Reflectence