Fig. 1. Schematic diagram of Zn diffusion mechanism in GaAs

Fig. 2. Diffusion of Zn in GaAs under the condition of 680 ℃ and 30 min

Fig. 3. Diffusion of Zn in InP under the condition of 680 ℃ and 30 min

Fig. 4. Thermal stress generated during annealing of epitaxial wafers with ZnO dielectric layer

Fig. 5. Thermal stress generated during annealing of epitaxial wafers with ZnO/SiO₂ and ZnO/Si₃N₄ dielectric layers

Fig. 6. Thermal stress values generated during annealing of epitaxial wafers with ZnO，ZnO/SiO₂，and ZnO/Si₃N₄ dielectric layers

Fig. 7. Schematic diagram of semiconductor laser device structure with epitaxial structure information and photoluminescence spectrum of the original epitaxial wafer

Fig. 8. Schematic diagram of Zn diffusion for the fabrication of non-absorbing window

Fig. 9. Blue shift at various temperatures in ZnO-covered and ZnO-uncovered regions

Fig. 10. PL spectrum of sample under annealing conditions of 650 ℃ and 30 min

Fig. 11. PL spectrums of sample after different temperature treatments

Fig. 12. Diagram of dielectric film cracking caused by excessive stress

Fig. 13. Peak wavelengths of sample 3 after different temperature treatments

Fig. 14. PL spectrums of sample 3 after 1~3 cycles of annealing at 620 ℃ in 30 min

Fig. 15. EDS maps of annealed sample 1 and sample 3

Fig. 16. Composition concentration of quantum well after Al diffusion at different distances

Fig. 17. Simulation results of the material gain spectral peaks with the changes of Al composition