An electrosurgical device includes a plurality of electrodes arranged to form a tissue treatment surface and a power supply. The power supply is configured to deliver a first drive signal with a first phase to at least a first one of the plurality of electrodes and a second drive signal with a second phase to at least a second one of the plurality of electrodes such that an electric field extends from the tissue treatment surface, where the first phase and the second phase are different. The power supply is further configured to receive an input from an operator of the electrosurgical device, and adjust the first phase or the second phase such that an aspect of the electric field extending from the tissue treatment surface changes in response to the input from the operator.