Diffusion of zinc into Ga1−xAlxAs

Abstract

A study of the diffusion of zinc into Ga1−xAlxAs with a ‘‘leaky tube’’ diffusion furnace has been carried out. The Ga1−xAlxAs epitaxial layers were grown with liquid phase epitaxy, and the aluminum concentration was varied from 0 to 44% in 4% increments; diffusions were performed in the temperature range 550–650 °C. It was found that the junction depth versus aluminum concentration was not a simple, monotonically increasing curve; rather, dramatic decreases in the apparent diffusion coefficient at xAl≊0.05 and xAl≊0.20 suggest that point defects, possibly including the DX center, are playing a significant role.

Stable single-mode operation of an 850-nm VCSEL with a higher order mode absorber formed by shallow Zn diffusion

“…3. We assume the hole concen-tration is 5 10 cm [11] and use the equation for the free carrier absorption [12] where wavelength in free space; electron charge; concentration of acceptor; light speed; refractive index of the semiconductor; free space permittivity; effective mass of holes; hole mobility, to find the optical loss which is dominated by the free carrier absorption in the Zn diffused region. It can be seen that the threshold gain increases rapidly from 850 cm at zero diffusion depth to 2000 cm at the diffusion depth of 0.1 m, then increases gradually and nearly monotonically with the diffusion depth.…”

Picosecond Raman Studies of the Electron-Phonon Interactions inAlxGa1−xAs: Nonmonotonic Dependenc

“…In addition, ordering can also occur near the points x 0.25, 0.75, in which case the luzonite and famatinite structures are favored. And, it is worth noting that an anomaly in the diffusion of zinc into Al x Ga 12x As near x 0.2 has been observed [12]. All of these effects suggest that the dielectric properties of Al x Ga 12x As are quite complicated, and a proper account of off-diagonal disorder, ignored also by Bonneville, must be incorporated into any proper nonlinear dielectric theory.…”