The full InGaN structure is used to achieve red light emitting diodes (LEDs). This LED structure is composed of a partly relaxed InGaN pseudo-substrate fabricated by Soitec, namely InGaNOS, a ndoped buffer layer formed by a set of In x Ga 1-x N/GaN superlattices, thin In y Ga 1-y N/In x Ga 1-x N multiple quantum wells, and a p doped In x Ga 1-x N area. p-doped InGaN layers are first studied to determine the optimal Mg concentration. In the case of an In content of 2%, an acceptor concentration of 1x10 19 /cm 3 was measured for a Mg concentration of 2x10 19 /cm 3 . Red electroluminescence was then demonstrated for two generations of LEDs, including chip sizes of 300x300 and 50x50 µm². The differences between these two LED generations are detailed. For both devices, red emission with a peak wavelength at 620 nm was observed for a pumping current density of 12 A/cm². Red light-emission is maintained over the entire tested current range. From the first to the second LED generation, the maximum external quantum efficiency, obtained in the range of 17 to 40 A/cm², was increased by almost one order of magnitude (factor 9) thanks to the different optimizations.