Group III nitride semiconductor crystal, production method thereof and group III nitride semiconductor epitaxial wafer
A technology for nitride semiconductors and epitaxial wafers, which is applied in semiconductor/solid-state device manufacturing, semiconductor devices, semiconductor lasers, etc., and can solve the problems of not being able to obtain III-nitride semiconductor crystals
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
example 1
[0060] The method of the present invention for producing a gallium nitride-based compound semiconductor crystal will be described below.
[0061] In Example 1, the first step is to pass a gas containing a gas obtained by mixing trimethylaluminum (TMAl) vapor with a trimethylgallium (TMGa) vapor in a molar ratio of 1:2 and a gas containing ammonia on the sapphire substrate. (NH 3 ) gas treatment, and the second step is the treatment of growing gallium nitride while feeding TMGa and ammonia gas. Two processes are performed to produce a GaN layer composed of gallium nitride crystals on a sapphire substrate. In the conditions used in the first step, the V / III ratio was about 85.
[0062] A sample including this GaN layer was produced by the MOCVD method according to the following procedure.
[0063] Before introducing the sapphire substrate, the material formed and grown inside the reaction chamber where the previous growth was performed in the same apparatus was nitrided by heat...
example 2
[0078] In Example 2, a test was performed through almost the same steps as in Example 1 except that the growth time of the Group III nitride semiconductor in the first step was 2 minutes. Also, in this case, the taken out wafer had a mirror surface and was colorless and transparent.
[0079] The cross-section of the sample was observed by a transmission electron microscope (TEM), and as a result, it was confirmed that island-like AlN grains existed at the interface between the sapphire substrate and the gallium nitride layer. According to elemental analysis, the grains contain about 15% Ga.
[0080] The same growth as that of this experiment was performed except that the process was stopped before growing the gallium nitride layer and the sample was taken out from the growth chamber, whereby samples were manufactured. The topography of the surface was observed by an atomic force microscope (AFM), and as a result, there were scattered aluminum nitride crystal grains having a r...
example 3
[0082] In Example 3, a sapphire substrate was introduced into the reaction chamber without baking prior to the growth following the previous experiment, and a first step of passing a gas containing trimethylaluminum (TMAl) vapor and passing TMGa and Ammonia to grow the second step of gallium nitride to produce a GaN layer comprising gallium nitride crystals on a sapphire substrate. The desired V / III ratio is 0 in this example, but a small amount of N atoms is provided on the substrate due to the decomposition of the material adhered to the wall or ceiling of the reaction chamber.
[0083] A sample including this GaN layer was produced using the MOCVD method according to the following procedure.
[0084] The sapphire substrate was introduced into a reaction chamber made of quartz placed inside the RF coil of the induction heater. The sapphire substrate was placed on a pedestal made of carbon for heating in a glove box purged with nitrogen, and after introducing the sample, nit...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More