Gallium nitride-based light emitting diode and preparation method thereof

Abstract

The invention provides a gallium nitride-based light emitting diode with high luminous efficiency and a preparation method thereof, and belongs to the field of photoelectric device preparation. The LED can maintain higher photoelectric conversion efficiency and a lower Droop effect under bulk current injection. The LED comprises a bottom layer and a light emitting layer which are grown through an MOCVD technology and a P-type layer which is grown through a molecular beam epitaxy technology, namely, a gallium polar buffer layer, a non-doped nitride layer, an N-type nitride layer and a multiple-quantum-well light emitting layer are grown through the MOCVD technology, and then, a sample is transferred to the reaction chamber of molecular beam epitaxy equipment, and a nitrogen polar electron blocking layer, a P-type nitride layer and a P-type nitride contact layer are grown. Through the method, band bending caused by polarization between the electron blocking layer and the multiple-quantum-well light emitting layer is reduced, the barrier height of electron overshoot to the P-type layer is increased, and the barrier height of hole injection to the multiple-quantum-well region is reduced.

Description

technical field [0001] The invention relates to the field of semiconductor optoelectronic device preparation, in particular to a preparation technology of gallium nitride-based LED with high light efficiency. Background technique [0002] The rapid development of wide bandgap III-V semiconductor materials has enabled the commercialization of high-brightness light-emitting diodes from green to near-ultraviolet. However, most of the current commercial LEDs are prepared by growing 001-plane nitrides on sapphire, silicon carbide or silicon substrates by MOCVD technology, and the surfaces are gallium polar planes. [0003] figure 1 A structure diagram of a conventional commercial gallium polar gallium nitride-based LED is shown, in which there is a strong polarization field between the multi-quantum well light-emitting layer 104 and the electron blocking layer 105 due to the difference in lattice constant. figure 2 It shows the energy band structure diagram of conventional com...

AI Technical Summary

Problems solved by technology

figure 2 It shows the energy band structure diagram of conventional commercial gallium polar gallium nitride-based LEDs. The electron blocking layer 104 generates positive charges at the interface due to tensile strain, causing the energy band to bend downward, so that the effective potential of the electron blocking layer in the conduction band is The barrier height is reduced, and the effective potential barrier in the valence band is increased, which not only reduces the electron blocking ability of the electron blocking layer, but also increases the potential barrier for holes injected into the multi-quantum well light-emitting layer on the p-type side.

Images