Figures

Figure 1a

A SEM image of the surface of the HVPE-GaN film.

Figure 1b

An AFM image of the surface of the HVPE-GaN film.

Figure 2

A photoluminescence spectrum taken at 2K.

Figure 3a

Monochromatic cathodoluminescence image taken at the peak of the edge emission - 360 nm.

Figure 3b

Monochromatic cathodoluminescence image taken at the peak of the red emission - 620 nm (b).

Figure 4

A SIMS image showing nonuniformities of oxygen distribution on the film surface.

Figure 5a

The evolution of the red emission spectra as a function of current.

Figure 5b

The integrated intensity of the red emission as a function of current.

Figure 6

The evolution of the red emission band as a function of accelerating voltage.

Figure 7a

The CL signal as a function of time at 620 nm at high current inside of a hexagonal defect.

Figure 7b

The CL signal as a function of time at 620 nm at high current outside of the same defect.

Figure 8

The PL decay characteristics at 650 nm.

© 2001 The Materials Research Society