A metallization scheme for gold on AlN is investigated that incorporates three layers sputter-deposited in succession on the AlN substrate, without breaking vacuum: 20 nm of Ti to promote adhesion, a 100 nm thick Ti-Si-N barrier layer, and 230 nm Au. The stability of the scheme was studied after annealing in vacuum up to 800°C for 30 min and at 400°C in Ar ambient for 300 h, using 2 MeV He 4 e + + backscattering spectrometry, sheet resistance measurements, and adhesion tests. It is shown that the incorporation of the diffusion barrier prevents the interaction of the Ti from the adhesion layer with the gold layer and thereby preserves the integrity of the metallization scheme. This metallization scheme may be applicable to other substrate materials.