Among the chemistries/polymers reported for the 193nm photoresist applications, methacrylate copolymers consisting of 2-methyl-2-adamantane methacrylate (2-MadMA) and mevalonic lactone methacrylate (MLMA) and cycloolefin polymers derived from derivatives of norbornene have shown promising results. We have studied the lithographic properties of these two different promising chemistries. Both systems offer linear resolutions down to 130 nm dense lines using conventional 193 nm illumination and high sensitivity at standard developer conditions. The etch rates of the methacrylate and cycloolefin based resists for polysilicon were found to be 1.4 and 1.3 times higher than that of novolak resist. Calculation of the normalized image log-slope (MILS) for both resist types shows that they can still resolve aerial images with a NILS of about 1.0, which is also confirmed by their 248 nm performance. The potential of 193 nm lithography is estimated at 110 nm dense line resolution if resists can be improved to match the performance of dense line resolution if resists can be improved to match the performance of the best current 248 nm resists which can resolve NILS values of about 0.7

Several representative tetraalkylphosphonium salts have been decomposed with potassium hydroxide in 70% aqueous dimethyl sulfoxide, a solvent greatly enhancing the nucleophilic activity of the hydroxide ion. The effects of ring size of cyclic phosphonium salts on cleavage products and rates are clearly evident with ring opening paralleling ring strain. Alcohols have been discovered to accompany phosphine oxide formation, but no alkenes resulting from Hofmann elimination were observed to form. The role of pseudorotation of pentacovalent intermediates is discussed in light of experimental findings.(1) (a) For a summary of pertinent references, see K. L. Marsi,

The thermolysis, ethanolysis, and ethanolysis with 2,6-lutidine reactions of 1,2-di-ferZ-butyl-1 -ethyldiazenium perchlorate (3) are reported. Clean first-order kinetics were observed for these reactions. The reactivity of 3 was found to be nearly the same for the various reaction conditions. Thermolysis of 3 yielded acetaldehyde ierz-butylhydrazonium perchlorate (4) and isobutylene (5) as products. Ethanolysis gave 4, 5, ethyl teri-butyl ether (6), acetaldehyde diethyl acetal (7), and mono-Zert-butylhydrazinium perchlorate (8). For ethanolysis with lutidine, the products were 5, 6, 7, trans-\,\-dimethylazoethane (10), and 1,2-di-ZerZ-butylhydrazinium perchlorate (11). The kinetic and product results for both thermolysis and ethanolysis are rationalized by a mechanistic sequence involving as key first steps a prototropic rearrangement of diazenium cation 3 to an ¡minium cation 14, which subsequently ionizes to ierl-butyl cation (13) and acetaldehyde zeri-butylhydrazone (12). For ethanolysis with lutidine, two separate competing mechanistic processes are indicated. One pathway involves direct ionization

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We review approaches that we have developed at 193 and 248 nm for first and second generation Radiation Sensitive Developable Bottom Anti Reflective Coatings (DBARC) and give an account of our most recent results for both types of DBARC's