Single crystal gan substrate, method of growing same and method of producing same

Abstract

The GaN facet growth method produces defect accumulating regions H on masks by forming a dotmask or a stripemask on an undersubstrate, growing GaN in a reaction furnace in vapor phase, inducing GaN crystals on exposed parts without covering the masks, inviting facets starting from verges of the masks and producing defect accumulating regions H on the mask. The defect accumulating regions H have four versions, that is, non (O), polycrystal (P), c-axis inclining single crystal (A) and orientation inversion (J). The best is the orientation inversion region (J). A sign of occurrence of the orientation inversion regions (J) is beaks of inversion orientation appearing on facets. GaN is grown on a masked undersubstrate by supplying a carbon material at a hydrocarbon partial pressure of 10 Pa to 5 kPa for 0.5 hour to 2 hour by an HVPE facet growth method without burying facets.

Description

technical field [0001] The present invention relates to single crystal gallium nitride (GaN) that can be used as a substrate of blue light emitting elements such as blue light emitting diodes (LEDs) and blue semiconductor lasers (LDs) composed of group III-V nitride semiconductors A substrate, a single crystal gallium nitride substrate (GaN) growth method, and a single crystal gallium nitride substrate (GaN) manufacturing method. Background technique [0002] Light-emitting elements using nitride-based semiconductors (InGaN, GaN) are already in practical use as blue LEDs. However, since GaN substrates with large areas cannot be obtained, insulating sapphire (α-Al 2 o 3 ) as the substrate. The LED structure was fabricated by growing GAN and INGAN films heterogeneously on the three-dimensional plane of symmetry of sapphire. Also, GAN-based LEDs using SIC substrates have been proposed and partially put into practical use. GAINN-like blue LEDs fabricated on sapphire substra...

AI Technical Summary

Problems solved by technology

This will increase the cost

[0006] The above are the shortcomings when used as LED substrates. In the case of semiconductor lasers (LDs), due to the lack of cleavage, there is the problem that the end faces of laser resonators cannot be made by cleavage.

The end face of the resonator must be formed by grinding and etching, which is time-consuming

There is another disadvantage: after all, the defect density is high

But there is such a problem: it is not just completely concentrated on one point, but somewhat scattered

Here, the messy displacement caused by blooming is the first problem

[0041] The second problem is: when the displacement is concentrated at the bottom of the pit 4 formed by the concave-convex surface 6, the planar defect 10 formed at the center of the pit is at an angle of 60° to each other.

However, there are problems when trying to make thick substrate crystals instead of thin films

Since the method uses a large amount of gas, the raw material gas yield is low

For thin films, this is not a problem, but for forming substrates, the low yield is a disadvantage

There is another problem: since the raw material contains organic matter and carbon, carbon will be mixed in when GaN is formed.

But the surface does not have 3-degree symmetry

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