How can I measure hall mobility of 2D materials?

Hall mobility, or electron mobility, of a 2D material is best measured by utilizing the Hall effect. There are several different Keithley solutions for making Hall effect measurements. A Keithley 4200A-SCS Parameter Analyzer with 4 Source Measure Units (SMUs) can be a suitable solution for low doped semiconductor materials. The 4200A-SCS allows for the van der Pauw resistivity measurement method to be utilized, as the device under test can be connected to SMUs at its four corners. Of course, 4 individual SMUs like the 2450 SMU can be used instead of the 4200A-SCS if you're willing to do the math required to extract mobility yourself. 

Another potential method for measuring the hall mobility of your 2D material is using the 3765 Hall Effect Card which was specifically designed for this purpose. This module achieves similar functionality to the previously described setup by buffering the 4 desired measurement points on the device under test. A DAQ6510 equipped with a 7709 6x8 Matrix Card and a 6220 Current Source also allows for a similar measurement process.