Spin castable mixtures useful for making deep-UV contrast enhancement layers

DETAILED DESCRIPTION What is claimed and sought to be protected by Letters Patent of the United States is as follows: 1.
Spin castable mixtures useful for applying contrast enhancement layers on photoresists capable of absorbing in the 200-300 nm region, wherein the contrast enhancement layers, upon being photobleached, are readily removable from the surfaces of the photoresists by stripping with a solvent, the spin castable mixtures comprising, by weight, (A) 100 parts of an inert solvent, (B) 2 to 20 parts of an inert organic binder, and (C) 2 to 20 parts of a nitrone of the formula, ##STR3## wherein R is selected from the group consisting of hydrogen, a C.
sub.
(1-8) alkyl radical, a C.
sub.
(3-5) divlalent alkylene radical, and a C.
sub.
(3-5) divalent alkylene radical substituted with one to three monovalent radicals selected from the group consisting of cyano, halogen, carbalkoxy, nitro, amino, alkylamino, and mixtures thereof, wherein X is hydrogen or a monovalent electron-withdrawing radical selected from the group consisting of carbalkoxy, acyl, and oxirane, and wherein Y is (i) hydrogen, or (ii) a monovalent aliphatic group selected from the group consisting of R.
sup.
1 and ##STR4## wherein R.
sup.
1 is a C.
sub.
(1-8) alkyl radical, wherein R.
sup.
2 and R.
sup.
3 are monovalent radicals selected from the group consisting of hydrogen and C.
sub.
(1-8) alkyl, and wherein Z is selected from the group consisting of hydrogen, C.
sub.
(1-8) alkyl radical, and an electron-withdrawing radical selected from the group consisting of nitrile, carbalkoxy, acyl, or (iii) a C.
sub.
(3-5) divalent alkylene radical, or (iv) a C.
sub.
(3-5) divalent alkylene radical substituted with one to three monovalent radicals selected from the group consisting of cyano, halogen, carbalkoxy, nitro, amino, alkylamino, and mixtures thereof, with the proviso that R and Y are divalent radicals only when both radicals react to form a C.
sub.
(5-7) ring.
2.
A spin castable mixture in accordance with claim 1, where the nitrone is .
alpha