High illumination efficiency solid state light-emitting device and manufacturing method thereof

This invention provides a high illumination efficiency solid state light-emitting device and its manufacturing method. The high illumination efficiency solid state light-emitting device includes a substrate, a diode unit, a plurality of epitaxy layers extending upwardly from the surface of the substrate and capable of emitting light when supplied with external electric energy, and a joining unit connecting the substrate and the diode unit, where the joining unit contains neither gold nor sliver. Since the joining unit has the features of low cost, high heat conduction performance, high strength, and high stability at high temperature, it is capable of reducing the cost and increasing the stability and reliability of the solid state light-emitting diode in the subsequent fabrication process, thus, increasing the yield rate and life of the solid state light-emitting diode. In addition, this invention also provides the fabrication method for the high illumination efficiency solid state light-emitting device.