Epitaxial growth method for improving crystal quality of aluminum nitride material, and aluminum nitride material

Abstract

The invention discloses an epitaxial growth method for improving the crystal quality of an aluminum nitride material, and the aluminum nitride material. The epitaxial growth method for improving the crystal quality of the aluminum nitride material comprises the following steps: growing and forming an aluminum nitride bottom layer on a substrate, growing an aluminum nitride hole forming layer on the aluminum nitride bottom layer, and simultaneously forming a plurality of holes in the aluminum nitride hole forming layer; and growing an aluminum nitride merging layer on the aluminum nitride hole forming layer, merging materials for forming the aluminum nitride merging layer at the top of each hole to form a cavity in situ, and wrapping the cavity in the aluminum nitride merging layer to make the epitaxial layer formed on the cavity have a flat and crack-free surface. The epitaxial growth method for improving the quality of the AlN material has the advantages of remarkable dislocation density reduction effect, capability of simultaneously inhibiting cracks, simple process, wide adaptability and the like, so that the thicker crack-free and high-quality AlN material grows, and the epitaxial growth method is completely suitable for commercial production.

Description

technical field [0001] The invention relates to the technical field of semiconductor material growth, in particular to an epitaxial growth method for improving the crystal quality of aluminum nitride (AlN) material and the obtained high-quality aluminum nitride material. Background technique [0002] AlN single crystal materials have a large band gap (6.2eV) and a direct bandgap energy band structure, so they are very suitable for deep ultraviolet optoelectronic devices, such as light-emitting diodes, lasers, detectors, etc. At the same time, AlN single crystal material also has excellent characteristics such as high breakdown voltage and small dielectric constant, which makes it have important application value in the field of power electronic devices. In addition, high-quality AlN single crystal materials are also the key to fabricate high-performance filters. [0003] Due to the difficulty in preparing AlN bulk single crystals and the small available size and high market...

AI Technical Summary

Problems solved by technology

Although such methods can effectively improve the quality of AlN thin film epitaxial crystals, the process is complicated and the process is numerous.

As a result, AlN thin film products not only increase the cost significantly, but also have low yield and poor uniformity, so this method is difficult to be practically applied to large-scale industrial production

Therefore, although other methods such as lateral epitaxy and pulsed atomic layer epitaxy can improve the quality of AlN thin film crystals to a certain extent, they are often time-consuming and complicated, resulting in high costs in actual production.

[0006] In summary, it can be found that the above-mentioned existing high-quality AlN epitaxial film growth methods mainly focus on improving the surface mobility of Al atoms, and hope to reduce the dislocation density by effecting GaN two-step growth, but the effect is either not ideal or obvious, The quality of the grown AlN is still poor, or the process is complex, requiring patterned substrates, secondary epitaxy and other processes, resulting in a series of problems such as cost and uniformity, and it is impossible to achieve a good balance between practicability and effect

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