EpiWorks and partners complete GaAsSb project
The GaAsSb material was grown by a process developed by EpiWorks, using source materials supplied by Epichem and InP substrates supplied by InPact.
State-of-the-art material quality was demonstrated in a multiwafer production reactor. The project goal to obtain a carbon-doped GaAsSb majority carrier mobility greater than 40 cm2/V.s for a doping level greater than 7x1019 cm-3 was achieved. Carbon doping levels above 8x1019 cm-3 were also demonstrated.
"With our partners, EpiWorks has developed an industry leading c-doped GaAsSb process," said Quesnell Hartmann, president of EpiWorks. "We are very excited about the results and have already begun applying the material in an HBT."
Hartmann says that GaAsSb HBTs are an important potential technology for high-speed digital and military applications and could be a breakthrough technology in high-speed wireless applications. "By developing the process on full 3-inch wafers, we have shown that the uniformity of GaAsSb is comparable to C-doped InGaAs, which is critical for HBTs," he said.
The process was developed in a production style MOCVD system, capable of producing eight 3-inch wafers or eight 4-inch wafers in a single production run. The single layer non-uniformity was less than 2% across the wafer as measured by the contactless resistivity measurement method.