Note: For ease of determination, for positive- and negative-tone resists respectively, contrasts are usually calculated as \[\gamma =\frac{1}{2\log_{10} (D_{\rm{n}}^{0.5}/D_{\rm{n}}^{0})} \quad {\rm{and}} \quad \gamma =\frac{1}{2\log_{10} (D_{\rm{p}}^1 /D_{\rm{p}}^{0.5})}\] in which \(D_{\rm{n}}^{0}\), \(D_{\rm{n,p}}^{0.5}\), and \(D_{\rm{p}}^{1}\) are the incident exposure doses to light or radiation required for incipient gel formation in a negative-tone system, the dose at \(\pu{50\%}\) of the original resist thickness remaining after development for either system, and the clearance dose for a positive-tone system, respectively.