NOVELTY - The device has a hollow component formed among semiconductor rods, a surface (1011) of a substrate (101), and a surface of a buffer layer e.g. undoped layer. Width of the hollow component is defined as largest size of the hollow component perpendicular to a normal direction (N) of the substrate, and height of the hollow component is defined as the largest size of the hollow component parallel with the normal direction of the substrate. A ratio of the height and the width of the hollow component is 1/5 to 3.    USE - Optoelectronic device e.g. vertical and horizontal type optoelectronic devices, for transferring electrical energy to light energy or vice-versa. Uses include but are not limited to an LED utilized in a traffic signal, backlight module, street light and in a medical instrument, laser diode, photoresistor, infrared emitter, organic LED, LCD, solar cell and a photo diode.    ADVANTAGE - The width of the hollow component is defined as the largest size of the hollow component perpendicular to the normal direction of the substrate, and height of the hollow component is defined as the largest size of the hollow component parallel with the normal direction of the substrate, where the ratio of the height and the width of the hollow component is 1/5 to 3, thus improving porosity of the hollow component, and hence improving light emitting efficiency.    DETAILED DESCRIPTION - The buffer layer is designed as an unintentional doped layer or n-type doped layer, where the device comprises protection layers made of silicon dioxide, hydrogen silesquioxane, methylsequioxane and polymer of silsequioxane. The protection layers are formed by a method of spin on glass coating. The substrate is designed as a conductive substrate, non-conductive substrate, and a transparent or non-transparent substrate. An INDEPENDENT CLAIM is also included for a method for manufacturing an optoelectronic device.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation illustrating a method for manufacturing an optoelectronic device.    Normal direction of substrate (N)    Substrate (101)    Semiconductor layer (102)    Surface of substrate (1011)