Model and Experimental Study of Surfactant Solutions and Pure Liquids Contact Angles on Complex Surfaces - Drops and Bubbles in Contact with Solid Surfaces - page 190

Ta b l e 1 .
AFM and XPS measurements. AFM measurements show roughness for smooth, coated silicon wafer, as well as plasma etched PTFE, etched aluminum and
AKD superhydrophobic surfaces. XPS results are for fluorinated or saturated hydrocarbon surface chemistries for each surface where applicable. Value in
parenthesis denotes standard deviation

Silicon PTFE Aluminum AKD

Teflon AF OTS

coated coated

Ra (nm) 48 (26) 8 (0.02) 1328 (410) 400 (190) 1248 (170)

Rq (nm) 57 (29) 14 (1) 1650 (780) 500 (210) 1530 (150)

Rmax (nm) 276 (73) 437 (92) 8741 (350) 3800 (370) 7820 (180)

Wenzel parameter r - 2.78 (0.15) 1.77 (0.15) 2.85 (0.27)

XPS Data Teflon AF OTS Naturally Fluorinated Teflon AF OTS Teflon AF Un-Coated

Coated Coated Coated Coated Coated

[F]:[C] [C-C] and [F]:[C] [C-C] and [F]:[C] [C-C] and [F]:[C] [C-C] and

[C-H] [C-H] [C-H] [C-H]

∼ 1.45 61.9% ∼ 1.2 N/A ∼ 1 58.8% ∼ 0.3 > 80%