A semiconductor device is disclosed. The semiconductor device comprises a light-emitting diode chip disposed in a cavity of a semiconductor substrate. At least two isolated outer wiring layers are disposed on the bottom surface of the semiconductor substrate and are electrically connected to the light-emitting diode chip, serving as input terminals. A lens module is adhered to the top surface of the semiconductor substrate to cap the cavity, in which the lens module comprises a molded lens and a molded fluorescent layer thereunder and the molded fluorescent layer faces the light-emitting diode chip. A method for fabricating the semiconductor devices is also disclosed.