Nitride LED

Abstract

The invention discloses a nitride LED which comprises an n-type nitride layer, a light-emitting layer and a p-type nitride layer in sequence. The light-emitting layer is of a multiple-quantum-well structure composed of barrier layers and well layers. An AlGaN electronic tunneling layer is inserted into at least one well layer close to the n-type nitride layer, the barrier height of the AlGaN electronic tunneling layer is larger than that of the corresponding barrier layer. The barrier of the AlGaN electronic tunneling layer and the barrier of the well layers are high enough, so that it is difficult for electrons to jump in the thermionic emission direction, the electrons mainly jump in the InGaN well layers in a tunneling mode, in this way, the migration rate of the electrons is limited, the distribution of the electrons is adjusted, and the probability that the electrons overflow to the p-type nitride layer is lowered.

Description

technical field [0001] The invention relates to the technical field of semiconductor materials, in particular to a nitride light-emitting diode. Background technique [0002] GaN-based light-emitting diodes are widely used in daily life. Compared with traditional light sources, LEDs have the excellent characteristics of long life, high luminous efficiency, low energy consumption, and small size, which is an important trend in the development of modern lighting. [0003] The light-emitting layer of traditional GaN-based LEDs generally uses InGaN / GaN Multiple Quantum Wells (MQW for short) structure. On the one hand, because the mobility of electrons is faster than that of holes, and the concentration of free electrons is higher than that of free holes, It is easy to cause uneven distribution of electrons and holes in the MQW. The electrons are concentrated in the MQW layer closer to the n-type layer, while the holes are concentrated in the MQW layer closer to the p-type layer....

AI Technical Summary

Problems solved by technology

[0003] The light-emitting layer of traditional GaN-based LEDs generally uses InGaN / GaN Multiple Quantum Wells (MQW for short) structure. On the one hand, because the mobility of electrons is faster than that of holes, and the concentration of free electrons is higher than that of free holes, It is easy to cause uneven distribution of electrons and holes in the MQW. The electrons are concentrated in the MQW layer closer to the n-type layer, while the holes are concentrated in the MQW layer closer to the p-type layer. The gradual decay in the n-type direction is not conducive to electrons and holes. On the other hand, due to the high electron concentration and fast migration, the electrons are easy to overflow into the p-type layer and recombine with the ionized holes in the p-type layer, which reduces the ionization efficiency of the holes and produces non- Radiative recombination, reducing hole injection efficiency and causing efficiency droop effect (Efficiency Droop)

[0004] Please see attached figure 1 At present, the high Al composition AlGaN (Al composition is generally 0.2~0.5) electron blocking layer is generally used to block the overflow of electrons. The high Al composition can limit part of the electron overflow to the P-type layer. , the ionization energy of Mg will increase rapidly and the crystal quality will decrease significantly, resulting in a sharp decrease in hole ionization efficiency and concentration, which in turn will cause a decrease in brightness and efficiency; in addition, under the condition of high current injection, high Al composition The AlGaN EBL structure still has a large number of electrons that will overflow to the P-type layer, causing problems such as Efficiency droop effect, aging and light decay

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