High-through-put, high-yield, and highly-reproducible (AlGa)As double-heterostructure laser wafers grown by molecular beam epitaxy

It is shown that high-through-put, high-yield molecular beam epitaxy, and highly reproducible (AlGa)As double-heterostructure (DH) laser wafers can be grown by molecular beam epitaxy (MBE) with properly designed multichamber MBE systems. This is demonstrated by growing two series of (AlGa)As DH laser wafers and measuring their broad-area threshold current density Jth distributions across the wafers (3.5 cm diameter). The first series consists of four different wafers grown consecutively at growth rates of 2.9, 4.2, 7.4, and 9.5 mm/h. The results show that the Jth’s are not affected by accelerated growth rates. In the second series, four DH laser wafers having the same layer structures were grown under the same conditions without interruption at 11.5 mm/h. The results show that even at such high growth rates the qualities of the DH laser wafers are still highly reproducible. The low-averaged Jth’s (∼700 A/cm2) of the present DH wafers in both series also show that the material and heterojunction qualities of these wafers are as good as those previously grown at lower growth rates (∼1.5 mm/h). The half-peak full-width of the Jth distributions across an area of 3-cm width of the wafers (3.5 cm diameter) are about 50–60 A/cm2. Such narrow range of distributions ensures high device yield.