A light-emitting device includes a substrate with light-emitting units. The light-emitting units include a first light-emitting unit, a second light-emitting unit, and one or more of third light-emitting units. Each of the light-emitting units includes a first semiconductor layer, an active layer and a second semiconductor layer. An insulating layer includes a first insulating layer opening and a second insulating layer opening formed on each of the light-emitting units. A first extension electrode covers the first light-emitting unit and the first extension electrode covers the first insulating layer opening on the first light-emitting unit. A second extension electrode covers the second light-emitting unit and the second extension electrode covers the second insulating layer opening on the second light-emitting unit. First and second electrode pads cover different parts of the light-emitting units.