Diazonaphthoquinone compounds

Lithographic Evaluation. To prepare the photosensitive polyimide solution, a polyimide precursor and a diazonaphthoquinone compound were dissolved in the... 

HPR-206 Positive Photoresist (Olin-Hunt) Mixed Isomer Novolac + Diazonaphthoquinone Photoactive Compounds 120-140... 

The photoactive compounds, or sensitizers, that are used in the formulation of positive photoresists, are substituted diazonaphthoquinones shown in Figure 17. The substituent, shown as R in Figure 17, is generally an aryl sulfonate. The nature of the substituent influences the solubility characteristics of the sensitizer molecule and also influences the absorption characteristics of the chromophor (79). The diazonaphthoquinone sulfonates are soluble in common organic solvents but are insoluble in aqueous base. Upon exposure to light, these substances undergo a series of reactions that culminate in the formation of an indene carboxylic acid as depicted in Figure 17. The photoproduct, unlike its precursor, is extremely soluble in aqueous base by virtue of the carboxylic acid functionality. 

The most popular photoactive compound, 1, is a substituted diazonaphthoquinone shown below together with a cresol-formaldehyde Novolak resin, 2 (5). There are many varieties of photoactive compounds that generate... 

Figure 2.9. The N-alkyldiazopiperidinedione structure is typical of the 1,3-diacyl-2-diazo compounds studied at IBM. Photolysis produces a carboxylic acid analogous to the chemistry of diazonaphthoquinones. These materials absorb strongly in the DUV region, but bleach completely as indicated in the spectra of a methanolic solution bottom). Resists formulated from these materials in novolac show residual unbleachable absorbance due to the resin as shown in the spectra of thin films (top).

Conventional positive photoresists consist of a matrix resin and a photoactive compound. The matrix resin is a cresol-formaldehyde novolac resin (structure 3.1) that is soluble in aqueous base solution, and the photoactive compound is a substituted diazonaphthoquinone (structure 3.2) that functions as a dissolution inhibitor for the matrix resin. As outlined in Scheme 3.1 (20), the photoactive compound undergoes a structural transformation upon UV radiation, known as WolflFrearrangement, foUowed by reaction with water... 

Willson et al. (30) and Miller et al. (31) described a new mid-UV resist based on diazonaphthoquinone and a novolac resin speciScally designed for use in the mid-UV region. The novolac resin was chosen to be transparent above 300 nm. The structure of the naphthoquinone was designed with the aid of semiempirical molecular orbital calculations to provide increased optical absorbance at the 313-nm emission line. They found that 5-alkylsulfo-nates of diazonaphthoquinone exhibit a greatly improved extinction at both 313 and 334 nm over their aryl counterparts. Furthermore, these compounds photolyze to give substituted indenecarboxylic acids that are transparent above 300 nm, whereas the photoproducts of all of the corresponding aryl derivatives studied retain residual absorbance at 313 nm. They chose a mixed 4,5-disulfonate of an aliphatic diol (structure 3.4) as a spectrally matched sensitizer for the mid-UV resist. 

Material. The resist material photoactive compound (PAC), a diazonaphthoquinone derivative in a novolak resin matrix, was used as a control and also reformulated to obtain PAC/pyrene. Pyrene was obtained from Aldrich and was added to the PAC in this study in the quantity of 2.5% of the total solids content of the resist. The resists were mixed on a roller overnight and then filtered through a 0.8pm silver membrane filter. 

The resist system which supported the i-line technology for many years in an exclusive manner was so-called diazonaphthoquinone (DNQ)/novolac resists (Fig. 5). This type of resists originally invented for printing by Suss [2] is a two-component system consisting of a novolac resin and a photoactive compound (PAC), diazonaphthoquinone. The novolac resin is soluble in aqueous base in virtue of the acidic phenolic OH functionality. However, the lipophilic diazonaphthoquinone dispersed in the phenolic matrix inhibits the dissolution of the resin film in an aqueous base developer. UV irradiation of the photoactive compound results in formation of a highly reactive carbene, accompanied... 

The resist sensitivity is a very important parameter to be considered as it is directly related to wafer throughput and therefore device manufacturing cost. Thus, sensitivity enhancement was a primary research activity in the field of microlithography in the 1970s and early 1980s. However, the enhancement of sensitivity achieved at that time was too incremental and marginal. Quantum yields, expressed as the number of molecules transformed per photon absorbed, characterize the efficiency of photochemical events. Typical diazonaphthoquinone has a quantum yield of 0.2-0.3, which means that three to five photons are needed to convert a single molecule of the photoactive compound. An in-... 

In addition to the oligomeric and polymeric dissolution inhibitors discussed earlier, small molecules bearing acid labile groups have been employed in 157 nm resist formulations [295, 312]. Representative examples are shown in Fig. 98. Some are better than others in dissolution inhibition of a copolymer of NBHFA and NBTBE (92 8). What is interesting is that a diazonaphthoquinone PAC developed for mid UV application (Fig. 99) [313] is surprisingly transparent and can inhibit the dissolution of PNBHFA even better than the small acid-labile dissolution inhibitors in Fig. 98 [312]. In contrast, the dissolution of PSTHFA cannot be efficiently inhibited either with diazonaphthoquinone, the small acid-labile lipophilic compounds in Fig. 98, or the carbon monoxide copolymer (Fig. 94) [312]. 

For resists designed for applications in the near-UV region, good absorption at 365 nm (i-line) and at 405 nm and 436 nra (g-line) is required, and aromatic substituents present the best option. The most commonly used ballast compound is polyhydroxybenzophenone, where one to three (or even four) hydroxyl groups can be esterified with diazoquinone sulfonyl-chloride, as discussed above. A popularly used dissolution inhibitor is a substituted 2,3,4-trihydroxy benzophenone of stmcture (in), " where DQ stands here for diazonaphthoquinone. One other popular diazoquinone derivative found in commercial resists is the sulfonyl ester of cumylphenol. Similar materials such as shown in structure (IV) have also been employed in resist applications. ... 

H. Meier and K. Zeller, The Wolff rearrangement of diazo carbonyl compounds, Angew. Chem. Int. Ed. (English) 14, 32 (1975) M. Kaplan, D. Meyerhofer, Response of diazoquinone resists to optical and electron beam exposure, RCA Rev. 40, 169 (1979) Sensitivity of diazoquinone resists to optical and electron beam exposure, Polym. Eng. Sci. 20, 1073 (1980), D. Ilten, R. Sutton, Spectrophotometric determination of photoresist photosensitivity, J. Electrochem. Soc. 119, 539 (1972) B. Broyde, Exposure of photoresists, J. Electrochem. Soc. 117, 1555 (1970). R. Dammel, Diazonaphthoquinone based Resists, p. 15, SPIE Press, Bellingham, WA (1993). " ibid., p. 17. 

This study explores the feasibility of developing positive tone resists that can be cast and developed from water alone. Its purpose is to determine which approaches might be suitable for the design of a positive tone water-soluble resist. Each of the components of an eventual resist are explored separately with the help of model reactions to develop guidelines for the design of an eventual positive-tone water-soluble resist system. Since neither the matrix resin (Novolac) nor the photoactive compound (diazonaphthoquinone) components of classical i-line resists (7) are water soluble, resists incorporating chemical amplification (2,3) were targeted. 

We report on the positive alkali-developable photosensitive polyimides based on an alkali-soluble polyimide precursor as a base polymer and diazonaphthoquinone (DNQ) sensitizer to improve process stability and sensitivity. Polyamic acid ester with pendant carboxylic acid (PAE-COOH) showed good dissolution behavior in aqueous alkali developer. The dissolution rate of PAE-COOH was controlled by the content of pendant carboxylic acid. It was found that a photosensitive system composed of butyl ester of PAE-COOH and a DNQ compound can avoid the residue at the edge of hole patterns (footing) after development, while that of methyl ester of PAE-COOH showed the residue. A DNQ compound containing sulfonamide derived from diaminodiphenylether renders improved sensitivity compared with DNQ compounds derived from phenol derivatives. 

Diazonaphthoquinone (DNQ) Compounds Preparation. 2.3,4,4 -tetrahydroxy-benzophenone-l,2-diazonaphthoquinone-5-sulfonate (average esterification ratio is 75%) (TBP-DNQ) was purchased from Tokyo Gosei Kogyo Co. Ltd. 4,4 -bis(l,2-diazonaphthoquinone-5-sulfonamino)diphenyl ether (DDE-Q) To a solution of 4,4-... 

In our study of diazonaphthoquinone dissolution, the quartz crystal microbalance was determined to be the most suitable measurement tedinique because of its high predsion. We are interested in isolating the role of photoactive compound (PAC) in inhibiting dissolution of the matrix resin. There have been numerous theories proposed whidi address the issue of the role of PAC during development (12-16). Our goal is to understand the physical range of influence exerted on the polymer matrix by individual PAC moieties as well as the effect of PAC spatial distribution on overall development behavior. 

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