Figures

Figure 1

Scheme of light-emitting diode.

Figure 2

Photoluminescence spectra of AlGaN/GaN/AlGaN DH grown on a 2.5 µm-thick undoped GaN layer.

Figure 3

SIMS profile of Al in a thick AlGaN layer grown directly on a sapphire substrate.

Figure 4

Photoluminescence spectra excited and detected both from the surface and from the sapphire substrate side for 2.5 µm - thick AlGaN layer. A typical PL spectrum for undoped GaN layer is also shown.

Figure 5

Electroluminescense spectra of sample a328 (a 0.1 µm Al0.04Ga0.96N / 0.2 µm GaN / 0.1 µm Al0.08Ga0.92N DH grown on 2.5 µm - thick GaN layer).

Figure 6

Electroluminescence spectra of LEDs with different bottom layers.

Figure 7

Electroluminescense spectra of structure a469 under different forward currents.

Figure 8

I-V characteristic of structure of a UV LED (a469).

© 1998 The Materials Research Society