High-throughput and fully automated system for molecular-beam epitaxy

摘要: A new high‐throughput and fully automated system for molecular‐beam epitaxy was developed by employing multiple substrate mount pallets automatic pallet transfer mechanisms. The geometrical configuration between effusion cells optimized to achieve the uniformity of thickness carrier concentration epitaxial layer better than ±2% within a pallet. throughput more 70 2‐in. wafers per day growth AlGaAs/GaAs two‐dimensional electron gas structure. In typical structure with 6‐nm spacer layer, variation sheet mobility closed in 7.5 10×104 cm2 /V s at 77 K over run run. By improving heater Ga cell, Ga‐related oval defect density found be reduced <1 cm −2. total surface <50 cm−2 preventing particulate contamination on surface. Moreover, unintentionally doped GaAs dominated donor, whose concentration...