We report on the formation of high-quality ohmic contacts to p-GaN (N-a = 4 x 10(17)/cm(3)) for UV flip-chip light-emitting diodes (LEDs) using a tin-zinc oxide (TZO) interlayer. It is shown that the TZO (2.5 nm)/Ag (250 nm) contacts produce contact resistivity of 1.58 x 10(-4) Omega cm(2) and reflectance of 76% at 405 nm when annealed at 530 degrees C. Near-UV LEDs made with the annealed TZO/Ag p-contacts give forward-bias voltage of 3.26 V at 20 mA, and higher output power than those with single Ag contacts. Based on transmission electron microscopy and electrical results, possible ohmic formation mechanisms are discussed. (c) 2005 The Electrochemical Society.