Advanced atomic layer deposition and epitaxy processes (Invited paper)

Atomic Layer Deposition (ALD) was used to grow single-crystalline epitaxial layers of high-k dielectric oxides on semiconductors with remarkably few defects or traps at the interfaces. La₂O₃ on GaAs(111) produced record-breaking transistors with both n-and p-channels, and CMOS circuits entirely in GaAs, including inverters, logic circuits and 5-stage ring oscillators. More conventionally oriented GaAs(100) substrates with etched (111) slopes also produced working transistors. ALD also grew single-crystalline epitaxial La₂O₃ films on Ge(111), and (Ca, Mg)O films on GaN(0001) substrates with high-quality epitaxial interfaces. These processes can be run in commercial ALD reactors using precursors produced by the Dow Chemical Company.