Self-organized InAs quantum dots (QDs) are grown in the Stranski–Krastanov regime, by molecular beam epitaxy, on (1 0 0) GaAs substrates. In order to grow high-quality QDs emitting at 1.3 μm, an unusual two-step growth procedure is first developed, with a growth interruption during the InAs deposition, just above the critical thickness. Then two important growth parameters are considered. First, the GaAs cap layer deposition rate is optimized, the InAs growth being kept constant. Second, the InAs growth rate is optimized, at optimized GaAs cap layer deposition rate. The optimizations leads to large QDs with a unimodal size distribution and the room temperature photoluminescence (PL) spectrum peaks at 1.3 μm with a 19 meV full-width at half-maximum (FWHM). These optical properties are at the international state of art. Then, three QD layers are stacked with different spacer thickness in order to increase the QD density necessary for laser applications. The best optical properties are obtained for the wider GaAs spacer (45 nm): PL emission around 1.3 μm, narrow FWHM (31 meV), and PL intensity enhanced by a factor of 3. The results are promising for further incorporation of the QD stacks in the active region of a laser.