New Hall System Offers Flexibility for Non-Destructive Testing of Wafer-Scale Materials

Measure Hall mobility on wafer-scale materials as a function of temperature and field with the new Model 8425 system from Lake Shore Cryotronics. Featuring an integrated cryogenic probe station, the system allows researchers to perform Hall measurements on wafers up to 51 mm (2 in) in diameter, eliminating dicing of fabricated wafers as typically required in a conventional Hall system. And because the sample is under vacuum, the platform is suited for testing materials that are reactive to air or require initial warming to drive out moisture. Repositionable probes eliminate the need for large fixed-wire contacts, and they enable multiple structures to be sampled on a wafer, including structures progressively built on wafer substrates. The system offers DC fields to 2 T, resistances from 10 µΩ to 100 GΩ, and measurements over a range of temperatures (from 10 K to 400 K). In addition, it supports van der Pauw, Hall bar and gated Hall bar measurements and includes the latest in Lake Shore Hall measurement software capabilities for easy control of magnetic field, sample excitation, sample temperature and automated temperature loops. DC field measurement capabilities are the same as those for Lake Shore’s other 8400 Series systems, including Hall voltage, IV curves, resistance and resistivity; and derived values include Hall coefficient, Hall mobility, carrier type, carrier density and magnetoresistance. For details, visit www.lakeshore.com.