A parametric investigation of GaAs epitaxial growth uniformity in a high speed, rotating-disk MOCVD reactor

Uniform GaAs epitaxial growth (<±2.5%) across > 95% of 2 inch and 3 inch wafers has been routinely achieved by parameter optimization in high-speed, rotating-disk reactors. Multi-layer AlGaAs/GaAs structures (doped and undoped) exhibit the same degree of uniformity. Uniformity, as characterized by thickness, sheet resistivity, impurity profile measurements, Hall effect measurement, photoluminescence, and X-rays, is unaffected by layer thickness over the range from tens of ångströms to several microns. Growth systems with single or multiple alkyl/hydride injectors were studied. These MOCVD reactors are generally operated at low mixed convection numbers and large spin Reynolds number (Re > 500). Parameters investigated are injector geometries, injector flows, rotation and carrier flows.