The　authors　propose　the　use　of　SU-8　to　passivate　the　isolation　trenches　of　GaN-based　high-voltage　light-emitting　diodes　(HV-LEDs).　Compared　with　the　HV-LED　chips　prepared　with　pure　SU-8　passivation,　it　was　found　that　we　could　increase　the　production　yield　from　＜=　35%　to　＞=　88%　using　properly　diluted　SU-8　passivation　layer.　It　was　also　found　that　we　could　reduce　the　passivation　layer　thickness　by　diluting　SU-8　with　a　ratio　of　5:2.　Furthermore,　it　was　found　that　the　properly　diluted　SU-8　could　provide　smooth　surface,　minimized　crack　formation,　and　thus　larger　production　yield.