Method of epitaxially growing submicron group III nitride layers utilizing HVPE

A method of epitaxially growing a thin Group III nitride layer utilizing HVPE techniques, the method comprising the steps of:

• locating a gallium (Ga) source in a quartz channel within a first source zone of an HVPE reactor, said Ga source having a exposed surface area of less than 4 square millimeters;
• locating a substrate within a growth zone of said HVPE reactor, wherein said growth zone is maintained at a first temperature;
• heating said Ga source to a second temperature;
• introducing a halide reaction gas into said first source zone to form a gallium chloride compound;
• transporting said gallium chloride compound to said growth zone;
• transporting a reaction gas to said growth zone, said reaction gas containing nitrogen (N);
• reacting said gallium chloride compound with said reaction gas to achieve an epitaxial growth rate of less than 0.1 microns per hour;
• growing the thin Group III nitride layer to a thickness of less than 0.02 microns;
• transferring said substrate to a growth interruption zone maintained at a third temperature, wherein said third temperature is within 50° C. of said first temperature;
• directing an inert gas in a flow direction that substantially prevents said gallium chloride compound and said reaction gas from entering said growth interruption zone;
• and
• discontinuing said steps of transporting said gallium chloride compound and said reaction gas to said growth zone.