| Popis: |
Visible laser diodes (LD), based on AlGaInP/GaInP/GaAs material system, are of great interest, because of large scale application in the information reading and aiming. Heterostructures for such a type of LD were grown successfully by MOCVD. As mentioned by most authors the main problem, which has place during the growth technology developments, is low value of temperature threshold coefficient T 0 . This problem is due to low conductive band discontinuity and p-doping efficiency. Holes concentration in p- cladding layer determine T 0 coefficient significantly, preventing leakage currents from active layer. Further it has been found, that hydrogen can passivate zinc atoms, incorporated into AlGaInP quaternary alloys. Comparing with AlGaAs/GaAs material system several new parameters should be controlled during AlGaInP layers growth: extent of ordering and growth rate. So, new degrees of freedom appears during growth and significantly affect growing results, epilayer parameters and, consequently, quality of manufactured laser diodes. This work is directed to show, how such growth parameters like: growth rate, growth temperature, and DMZn gas phase concentration; determine heterostructure quality. |
