A skin surface is treated with bipolar RF energy. A first semiconductive cap disposed on a first distal end of a first electrode and a second semiconductive cap disposed on a second distal end of a second electrode are applied to the skin surface. RF energy is delivered from the first electrode and the second electrode through the first semiconductive cap and the second semiconductive cap, respectively, through the skin surface. A thickness of each semiconductive cap between a blunt skin contacting surface and a curved surface affixed to a respective electrode is thicker at an inner portion and thinner at a center portion to homogenize the electrical field at the skin surface.