We report the growth over 2 in. sapphire substrates of crack-free fully epitaxial nitride-based microcavities using two highly reflective lattice-matched AlInN/GaN distributed Bragg reflectors (DBRs). The optical cavity is formed by an empty 3lambda/2 GaN cavity surrounded by AlInN/GaN DBRs with reflectivities close to 99%. Reflectivity and transmission measurements were carried out on these structures, which exhibit a stopband of 28 nm. The cavity mode is clearly resolved with a linewidth of 2.3 nm. These results demonstrate that the AlInN/GaN system is very promising for the achievement of strong light-matter interaction and the fabrication of nitride-based vertical cavity surface emitting lasers. (C) 2005 American Institute of Physics. [DOI: 10.1063/1.1849851]