Stability issues of quaternary CdZnSSe and ternary CdZnSe quantum wells in blue—green laser diodes

• Published in: Journal of crystal growth Vol. 184; pp. 580 - 584
• Main Authors: Behringer, M., Ohkawa, K., Großmann, V., Heinke, H., Leonardi, K., Fehrer, M., Hommel, D., Kuttler, M., Strassburg, M., Bimberg, D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1998
• Subjects: Cd diffusion; CdZnSSe; Degradation; II–VI laser diodes; Thermal stability; Degradation; 66.30. −h; 78.66.HF; II–VI laser diodes; 81.05.Dz; 61.10. −i; CdZnSSe; Thermal stability; Cd diffusion
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(98)80121-8

Thermally induced Cd diffusion in CdZn(S)Se/Zn(S)Se multi-quantum well-structures has been investigated in order to study point defects and their generation in II–VI/III–V heterostructures and to find a thermally stable quantum well design. Samples were annealed in Zn atmosphere and diffusion coefficients were determined with secondary ion mass spectroscopy. Cd diffusion coefficients as low as 1.2 × 10 −18 cm 2/s at T = 575°C were found in a CdZnSSe/ZnSSe structure. Samples annealed in Zn atmosphere indicate a higher stability of CdZnSSe than of CdZnSe, but samples annealed in N 2 seem to show the opposite tendency. Laser diodes show low threshold current densities of 400 A/cm 2 for both kinds of wells.