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A H2pre-bake at temperatures over 1050°C is typically used prior to Si epitaxial growth. In this study surface microroughness probed with tapping mode Atomic Force Microscopy (AFM) is correlated with multiple internal reflection infrared spectroscopy measurements for the different steps involved before epitaxy. A novel sample preparation technique was used for the multiple internal reflection set-up. A strong correlation was found between the presence of surface terraces and the IR double monohydride peaks for H2annealed Si surfaces. We therefore put forward that the terraces are due to the H2pre-bake step. These terraces remain after epitaxial deposition.

Cluster tool furnace technology was used to control the growth of extremely uniform ultra-thin 1.5 nm to 3 nm SiO2layers on Si. The transition from Fowler-Nordheim tunneling to direct tunneling electron injection for sub-3-nm oxide poly-Si gate metal-oxide-silicon capacitor structures is described and the influence on the oxide reliability is discussed. It is shown that oxide breakdown can still occur at low voltages in the direct tunneling regime under the condition of electron injection from the poly-Si gate. Soft breakdown of these ultra-thin oxide layers, accompanied by the occurrence of complex fluctuations in the direct tunneling current, is demonstrated. Using this as the definition of sub-3-nm oxide breakdown, it is shown for the first time that the time to dielectric breakdown of the sub-3-nm gate oxide in the direct tunneling regime is determined by the electrical field strength in the oxide similarly to the case of the sub-3-nm dielectric breakdown in Fowler-Nordheim tunnel stressing.