ABSTRACT
The causes of compositional uniformity for InGaAsP grown on InP substrates by OMVPE include, in addition to the well documented temperature sensitivity, a leading edge effect that has not been widely recognized. This is due to In being carried from the wafer carrier surface and changing the composition of the gas stream near the wafer edge, and affects both single wafer and multiple wafer reactors. To overcome this effect we designed a susceptor/wafer carrier combination that reduces the temperature differential between the wafer and its carrier. Differences in PL wavelength between the leading and trailing wafers were reduced from several nm to less than 2 nm for a six 2” wafer high speed rotating disk reactor, while wafer uniformities also improved.
