disclosed is a multi - quantum - well light emitting diode , which makes enormous adjustments and improvements over the conventional light emitting diode , and further utilizes a transparent contact layer of better transmittance efficiency , so as to significantly raise the illuminance of this light emitting diode and its light emission efficiency . the multi - quantum - well light emitting diode has a structure including : substrate , buffer layer , n - type gallium - nitride layer , active light - emitting - layer , p - type cladding layer , p - type contact layer , barrier buffer layer , transparent contact layer , and the n - type electrode layer .