Tunable EOT Scaling Down to 0. 55 nm for HfO2-Based Gate-Stacks on Ge Substrate by In Situ H2 Plasma Treatment

We propose a continuous fabrication method for HfO2-based gate stacks on a Ge bulk p-type metal–oxide–semiconductor capacitor (pMOSCAP) with HfGeOx interfacial layer by H2 plasma treatment through in situ plasma-enhanced atomic layer deposition. The electrical characteristics showed that the proper hydrogen plasma treatment could obtain an aggressively scaled equivalent oxide thickness of approximately 0.55 nm and a relatively low gate leakage current of 8 × 10-4 A/cm2 under PMA 500C.