Fig. 6From: Growth and Selective Etch of Phosphorus-Doped Silicon/Silicon–Germanium Multilayers Structures for Vertical Transistors ApplicationSEM images of P-doped Si/Si0.86Ge0.14/P-doped Si in Fig. 2c with a 11.5-s dry etch, b 20-min wet etch, and P-doped Si0.93Ge0.07/Si0.78Ge0.22/P-doped Si0.93Ge0.07 MLs with c 11.5-s dry etch, d 20-min wet etch. The dry etch was CF4:O2:He = 4:1:5, and the wet etch was HF (6%):H2O2 (30%):CH3COOH (99.8%) = 1:2:4Back to article page