Patent ID: 7670435

Claim:
A reactor for growing a multi-layer Group III nitride semiconductor device on a substrate in a single epitaxial growth run using hydride vapor phase epitaxy, the multi-layer Group III nitride semiconductor device having sharp layer-to-layer interfaces, the reactor comprising: a reactor tube; a first source tube positioned in the reactor tube and having a source material, the first source tube facing a first direction; a growth zone in the reactor tube; a first reactive gas source for supplying a first reactive gas that is introduced into the first source tube such that the first reactive gas can react with the source material to form a first reaction product that flows through the first source tube and is released through an outlet of the first source tube to flow into the growth zone; a second reactive gas source for supplying a second reactive gas that is delivered to the growth zone such that the second reactive gas can react with the first reaction product and cause growth of a layer on the substrate located in the growth zone; an inert gas source for supplying an inert gas; and a gas inlet tube connected to the inert gas source and arranged with its outlet end configured towards the upper surface of the substrate in, the growth zone, the gas inlet tube facing a second direction that is substantially opposite to the first direction, the growth zone and the substrate being located between the outlet of the first source tube and an outlet of the gas inlet tube such that inert gas can flow through the gas inlet tube, into the growth zone and over the substrate to controllably alter the flow of the first reaction product and the second reactive gas into the growth zone to controllably alter the growth rate of the layer on the substrate in the growth zone.