Surface recession definition

But this is usually not the case. The reason is that in imprint lithography, mold durability is maintained by choosing the proper polymer resist layer thickness such that the mold protrusion will not contact the hard substrate directly. In other words, a thin viscous polymer fluid exists between the mold protrusions and the substrate surface and acts as a soft cushion, which effectively protects the nanofeatures on the mold. The trade-off of this is the existence of a residual resist layer that is present in the recessed regions, which has to be removed by a separate plasma etching step before pattern definition can be completed. 

Techniques such as SIMS and XPS have sufficient surface sensitivity and small area analysis capability to tackle cratering problems. It is often necessary to determine if the crater is truly a de-wetted area or simply a recess in the coating brought about by local contamination. The spectrum per point analysis mode enables such questions to be resolved quickly and definitively. A combination of... 

Most surfaces have heterogeneous composition and are not perfectly smooth. Wetting of such a surface may reach equilibrium or remain in a metastable state. In the case of an ideal surface, the addition or removal of a small volume of liquid from the drop will result in the advancement or recession of the drop. The contact angle will return to its equilibrium value. In the case of a surface that may contain roughness and heterogeneity, there is a delay in the movement of the liquid drop in response to the addition or removal of liquid. This phenomenon, called hysteresis, requires a revision of the definition of contact angle. 

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