A LED chip including a first semiconductor layer; an active layer; a second semiconductor layer; a plurality of indentations, wherein each indentation extends downward to reach and expose the first semiconductor layer, wherein each indentation includes a bottom part and two side surfaces in a cross sectional view; an exposing area exposing the first semiconductor layer at a side of the LED chip; a first metal layer disposed on the second semiconductor layer and electrically connecting to the first semiconductor layer; and a first insulating layer formed between the first metal layer and the second semiconductor layer to isolate the first metal layer from the second semiconductor layer; wherein the first metal layer continuously extends to the plurality of indentations, covers the bottom part, the two side surfaces of each indentation and a top surface of the second semiconductor layer around the two side surfaces and contacts the exposing area; and wherein the first metal layer includes a plurality of recesses corresponding to the plurality of indentations.