Table 3.
Angle-resolved XPS determined elemental compositions of NH2-SAMs on Au.
| Atomic % (StdDev)* | |||||
|---|---|---|---|---|---|
| TOA | Au | C | O | N | S |
| 0 | 41.1 (2.5) | 49.9 (2.5) | 3.1 (0.3) | 4.2 (0.5) | 1.7 (0.1) |
| 55 | 28.5 (2.4) | 61.7 (2.7) | 3.4 (0.6) | 4.7 (0.4) | 1.8 (0.1) |
| 75 | 17.3 (1.3) | 70.2 (1.4) | 4.7 (0.6) | 5.9 (0.6) | 1.8 (0.1) |
| Atomic % Ratios (StdDev)* | |||||
|---|---|---|---|---|---|
| TOA | C/Au | N/Au | S/Au | O/Au | O/N |
| 0 | 1.21 (0.10) | 0.10 (0.01) | 0.04 (0.00) | 0.08 (0.01) | 0.75 (0.11) |
| 55 | 2.16 (0.21) | 0.16 (0.02) | 0.06 (0.01) | 0.12 (0.02) | 0.71 (0.13) |
| 75 | 4.05 (0.31) | 0.34 (0.04) | 0.10 (0.01) | 0.27 (0.04) | 0.79 (0.12) |
*
Average experimental composition from three distinct samples (one spot per sample). All data were taken at 0°, 55°, and 75° takeoff angles in the electrostatic mode. Note: the takeoff angle is defined as the angle between the surface normal and the analyzer.