NOVELTY - The method comprises providing a common growth substrate (210), forming a light-emitting epitaxy structure (220) on the common growth substrate, forming a stripping layer (230) on the light-emitting epitaxy structure, forming a solar cell epitaxy structure (240) on the stripping layer, forming an adhesive layer on the solar cell epitaxy structure, providing a solar cell permanent substrate on the adhesive layer, and removing the stripping layer using a wet etching solution containing hydrofluoric acid or citric acid to form a light-emitting device and a solar cell device separately.    USE - The method is useful for manufacturing optoelectronic devices (claimed) such as light emitting devices and solar cell devices, where the light emitting devices are useful as light sources for illumination and useful for traffic signal, backlight module, street light and medical instruments.    ADVANTAGE - The portable light emitting device has improved lifespan, light weight and less power consumption.    DETAILED DESCRIPTION - The method comprises providing a common growth substrate (210), forming a light-emitting epitaxy structure (220) on the common growth substrate, forming a stripping layer (230) on the light-emitting epitaxy structure, forming a solar cell epitaxy structure (240) on the stripping layer, forming an adhesive layer on the solar cell epitaxy structure, providing a solar cell permanent substrate on the adhesive layer, and removing the stripping layer using a wet etching solution containing hydrofluoric acid or citric acid to form a light-emitting device and a solar cell device separately. The step of forming the light-emitting epitaxy structure, the stripping layer and the solar cell epitaxy structure comprise metal organic chemical vapor deposition process, liquid phase deposition process or molecular beam epitaxy process. A material of the adhesive layer comprises metal, silver glue, conductive polymer, polymer materials mixed with conductive materials, or anisotropic conductive film. The step of forming the light-emitting device comprises forming a transparent conductive layer on the light-emitting epitaxy structure; forming a first electrode on the transparent conductive layer; forming a second electrode under the common growth substrate opposite to the light-emitting epitaxy structure; and dicing the transparent conductive layer, the light-emitting epitaxy structure, the common growth substrate and the second electrode along a cutting line. The step of forming the solar cell device comprises: forming an anti-reflective layer on a portion of the solar cell epitaxy structure; forming a first electrode on the remained portion of the solar cell epitaxy structure; forming a second electrode under the solar cell permanent substrate opposite to the adhesive layer; and dicing the anti-reflective layer, the solar cell epitaxy structure, the adhesive layer, the solar cell permanent substrate and the second electrode along a cutting line. INDEPENDENT CLAIMS are included for:    (1) a backlight module device;    (2) an illumination device; and    (3) a solar cell module.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of a process flow for manufacturing a light emitting device and solar cell device.    Common growth substrate (210)    Light-emitting epitaxy structure (220)    Stripping layer (230)    Solar cell epitaxy structure. (240)