  We report on the fabrication and characterization of a device which allows
the formation of an antidot lattice (ADL) using only electrostatic gating. The
antidot potential and Fermi energy of the system can be tuned independently.
Well defined commensurability features in magnetoresistance as well as
magnetothermopower are obsereved. We show that the thermopower can be used to
efficiently map out the potential landscape of the ADL.
