Depth profiling cross-linked poly(methyl methacrylate) films: a time-of-flight secondary ion mass spectrometry approach.

We demonstrated that the ion intensity ratio of C6 H- to C4 H- detected in TOF-SIMS provides a unique and simple means to assess the degree of cross-linking of the surface of PMMA films cross-linked by the surface sensitive hyperthermal hydrogen projectile bombardment technique. With a C60+ sputter beam, we were able to depth profile the PMMA films and determine cross-linking depths of the cross-linked polymer films at nanometer resolutions. Copyright © 2017 John Wiley & Sons, Ltd.