Figure 2.

The percentage difference of the surface conductivity is taken between the post-exposure measurement and the previously-measured point. Error bars represent one standard deviation from the linear fit of surface conductivity (see Figure 1(c)). (a) This graph shows the various measurements of the surface conductivity after different types of exposures, where each exposure is represented by a data point with a different color. The shaded region indicates the region in which the vertical axis is zoomed for the 50 nm and 100 nm samples. (b) With the exception of the initial deposition of a-BN, a 50 nm encapsulation prevents percentage differences from exceeding 10 %. The color, transparency, and style of data point of the curve is only meant to be a guide to the eye for the three different samples with this encapsulation thickness. (c) Keeping the vertical axis for the lowest numerical range identical in size and scale as the 50 nm case, the four 100 nm-thick a-BN samples also retain stable surface conductivity, to within 10 % of the previously-measured value. Curve transparency and data point style are guides to the eye.