Abstract: A fan is provided. The fan includes a frame, a rotor and a stator. The rotor is received in the frame and includes a magnetic part, a metal housing, a hub and a plurality of blades. The metal housing is telescoped on the magnetic part. The hub is telescoped on the metal housing. The blades are formed on the hub. The stator is received in the frame. The stator includes a plurality of silicon-steel sheets which form a silicon-steel sheet outside diameter, the silicon-steel sheet outside diameter is greater than 42 mm and wherein the rated speed of the fan is greater than 8000 RPM.

Abstract: A light-emitting device having a light-emitting epitaxy structure. The light-emitting epitaxy structure has a modulus of a critical reverse voltage not less than 50 volts, while the light-emitting epitaxy structure is reverse-biased at a current density of ?10 ?A/mm2, and has a luminous efficiency not less than 50 lumen/Watt, while the light-emitting epitaxy structure is forward-biased at a current density of 150 mA/mm2.

Abstract: The disclosure provides a light-emitting device comprising a light-emitting epitaxy structure. The light-emitting epitaxy structure has a modulus of a critical reverse voltage not less than 50 volts while the light-emitting epitaxy structure is reverse-biased at a current density of ?10 ?A/mm2, and has a luminous efficiency not less than 50 lumen/Watt while the light-emitting epitaxy structure is forward-biased at a current density of 150 mA/mm2. Another aspect of the present disclosure provides a manufacturing method for a light-emitting device.