Design and process development of a novel multi-wafer OMVPE reactor for growing very uniform GaAs and AlGaAs epitaxial layers

A unique multi-wafer OMVPE reactor with capability to produce atomic-layer abrupt-ness is demonstrated. Uniform GaAs and AlGaAs epitaxial layers were grown on four two-inch wafers or one three- or four-inch wafer. Thickness variation across a three-inch wafer was less than ±2%, while the variation of Al solid composition was less than ±1%. Multiple AlGaAs/GaAs quantum wells ranging in size from 10Å to 140Å were grown with heterointerface roughness less than one monolayer. The electrical properties of HEMT device were studied. Variations of sheet carrier concentration and electron mobility were ±6% and ±5% respectively across a three-inch wafer. The carrier con-centration profile, mobility spectrum and device characteristics of DH-HEMT are also presented. These results indicate that this OMVPE reactor can grow good device struc-tures for microwave and millimeter-wave power device applications.