Figure 1From: Characterization of epitaxial GaAs MOS capacitors using atomic layer-deposited TiO2/Al2O3 gate stack: study of Ge auto-doping and p-type Zn dopingAFM images (10 × 10 μm2) for epitaxial GaAs on Ge structures. (a) Undoped epi-GaAs and Zn-doped epi-GaAs with doping densities of (b) 1 × 1017 cm-3, (c) 1 × 1018 cm-3, and (d) 1 × 1019 cm-3. The rms surface roughness of the structures determined from AFM is (a) 4.0 nm, (b) 4.7 nm, (c) 4.4 nm, and (d) 4.6 nm.Back to article page