An apparatus and method for use in performing ablation of organs and other tissue includes an electrode carrying member which is substantially absorbent and/or permeable to moisture. The electrode carrying member is mounted to the distal end of an elongate shaft, and an array of electrodes is mounted to the surface of the electrode carrying member. Following placement of the ablation device into contact with the tissue to be ablated, an RF generator is used to deliver RF energy to the electrodes and to thereby induce current flow from the electrodes to tissue to be ablated. As the current heats the tissue, moisture (such as water vapor or liquid) leaves the tissue causing the tissue to dehydrate. The moisture permeability and/or absorbency of the electrode carrying member allows the moisture to leave the ablation site so as to prevent the moisture from providing a path of conductivity for the current.