A holder is disclosed, wherein the holder is situated on a circuit board and is used for connecting with an electronic component. The holder comprises an upper surface, a lower surface, and an opening. The upper surface comprises a recess used for laying a flat component, wherein the recess comprises at least one rough area; the lower surface comprises a protruding edge, wherein the protruding edge is connected with the circuit board with glue, and the protruding side and the circuit board delimit a space; and the opening penetrates the upper surface and the lower surface, whereby the gas generated from heating the glue will accumulate in the enclosed space, and the gas will then escape through the opening and out through at least one of the rough areas.