Figure 7
C 1s X-ray photoelectron spectroscopy (XPS) data. (a) The PDMS surface after 10 min etching by 0.2 torr XeF2 gas and 200 mA ring current. The SR beam was attenuated to about 13% by the slit. The etching chamber was evacuated for about 3 h before etching. The XPS was measured using an Au thin film covering the non-etched area of the PDMS surface. (b) The surface of PDMS without etching. (c) Au thin film used to cover the non-etched area of the PDMS surface. Peaks P1 (284.7 eV), P2 (285.7 eV) and P3 (287.7 eV) are assigned to carbon contained in the bulk PDMS, the hydrogen-containing carbon material (CxHy) deposited by the etching, and the carbon contamination on the Au thin-film surface, respectively. |