Silicon-base compound substrate and manufacturing method thereof

Abstract

The invention provides a silicon-base compound substrate for preparing a nitride semiconductor epitaxial material, and a manufacturing method of the silicon-base compound substrate. The silicon-base compound substrate comprises a silicon monocrystal substrate, a compound stress covariant layer which is formed on the silicon monocrystal substrate and formed by frequently stacking aluminum nitride and a titanium nitride monocrystal thin film material, and a gallium nitride template layer which is formed on the compound stress covariant layer and consists of a gallium nitride monocrystal thin film material. By the silicon-base compound substrate, the crystal lattice and big heat mismatch problems of the silicon-base gallium nitride material are solved; therefore, the preparation cost of a gallium nitride light emitting diode (LED) epitaxial sheet can be reduced greatly; and the silicon-base compound substrate is suitable for application and market popularization.

Description

technical field [0001] The invention relates to a semiconductor substrate and a manufacturing method thereof, in particular to a silicon-based composite substrate for preparing nitride semiconductor epitaxial materials and a manufacturing method thereof. Background technique [0002] Nitride semiconductors, especially gallium nitride (GaN) are the core basic materials for preparing light-emitting diode devices used in the fields of semiconductor lighting and display backlighting. Due to the lack of homogeneous single-crystal materials, device applications of GaN materials are usually carried out on heterogeneous substrates, most commonly sapphire (Al 2 o 3 ) substrate, because the sapphire substrate is non-conductive, hard and expensive, it has been difficult to reduce the difficulty and cost of GaN-based LED devices on it. Compared with sapphire and GaN, silicon carbide (SiC) substrate has a better lattice matching relationship, but it is expensive, and the GaN-based LED ...

AI Technical Summary

Problems solved by technology

The deterioration of crystal quality caused by lattice mismatch stress will greatly affect the optoelectronic properties of GaN materials;

[0004] (2) thermal mismatch problem

If such a large thermal tensile stress cannot be transferred and released in a coordinated manner, it will cause cracks or bending of the GaN film layer, making subsequent LED device structure preparation impossible;

[0005] (3) Interface chemistry issues

The patterned substrate method requires masks and photolithographic patterns (nano- or micron-scale patterns) on the silicon substrate or GaN epitaxial layer. Because the dislocation density at the window is difficult to reduce, multiple masks and photolithographic patterns are required, and the process is complicated. , which not only greatly increases the cost of material preparation, but also makes it difficult to obtain large-size GaN epitaxial layer materials with no cracks and bends and uniform crystal quality, such as GaN epitaxial layer materials with a diameter of more than 2 inches

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