Figures

Figure 1a

Luminescence spectra of a blue LED at J = 0.15 mA( spectra are normalized at the maximum of the blue line); numbers at the curves are the hours of aging at J = 80 mA.

Figure 1b

Luminescence spectra of a green LED at J = 0.15 mA; numbers at the curves are hours of aging at J = 80 mA.

Figure 2

Breakdown luminescence spectra of a blue LED at J = - 4 mA; numbers at the curves are hours of aging at J = 80 mA.

Figure 3

Current-voltage characteristics of a blue (b) and a green (g) LED's before (1) and after (2) aging at J = 80 mA during 800 hours.

Figure 4

Distribution of the effective charged centers concentration on the p-side of the space charge region of blue (b) and green (g) LED's before and after aging at J = 80 mA: 1) t=0; 2) t=250 hours; 3) t=1000 hours.

Figure 5

A model of electron transfer from the n- to the p-side of the heterojunction with a compensated layer: a) - at U<k, b) at U k, c) at U>k; 1 - n-GaN; 2,4 - compensated layers; 3 - InGaN (the active layer), 5 - p-AlGaN.

Figure 6

Changes of the effective concentration of charged centers in the space charge region of heterojunctions of blue (upper, at x = 0.67 lfp, a) ) and green (lower, at x = 3 lfp, b) LED's, lfp 3.10-6 cm. Values of x and points -squares- experimental data (Figure 4); points - circles luminescent intensity at J = 15 mA (right scale); curves - calculations by equations (6-8).

© 1998 The Materials Research Society