A light-emitting device, includes a substrate with a top surface; a first light-emitting structure unit and a second light-emitting structure unit separately formed on the top surface and adjacent to each other, and wherein the first light-emitting structure unit includes a first sidewall and a second sidewall; a trench between the first and the second light-emitting structure units; and an electrical connection arranged on the first sidewall and the second light-emitting structure unit, and electrically connecting the first light-emitting structure unit and the second light-emitting structure unit; wherein the first sidewall connects to the top surface; wherein the first sidewall faces the second light-emitting structure units, and the second sidewall is not between the first light-emitting structure unit and the second light-emitting structure unit; and wherein the second sidewall is steeper than the first sidewall.