Resist dry processed

In general, the photoresists exhibit greater dry-process resistance than the vinyl polymers of Table II. The greater dry-etch resistances of photoresists is attributed to the aromatic nature of the crosslinking agents, photoactive components, and novolac resins (positive photoresists only). In addition, the... 

And finally, is there then a PE rate ratio guideline for predicting resistance to more harsh and anisotropic RIE and ionmilling etches The answer to this question is empirically found to be yes. When the PE rate ratio is 0.3-0.5, the dry-process compatibility is usually very good. For resists with ratios ranging from 0.5 to 1, marginal to unsatisfactory behavior is usually observed, while polymers with ratios greater than one usually exhibit poor to totally unacceptable performance. For example, PS, PCMS and many positive photoresists exhibit etch rate ratios <0.5, and are proven dry-process resists. 

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