Negative work

The Fuji CopiArt monochrome proofing system is based on the photogeneration of color from leuco dyes or diazo-coupling (35). CopiArt includes both positive and negative working systems (Fig. 6). For the positive working system, a diazo compound (6) reacts with a coupler (7) as shown. 

Fig. 6. CopiArt proofing system (a) stmcture of positive working system, where A = organic base, = coupler, Q = microcapsule, and = diazo compound and (b) stmcture of negative working system, where A = photoinitiator, = leuco dye, Q — microcapsule, and...

Overlay Proofing. Overlay proofing systems can be categorized as wet- or dry-processed systems. The negative working wet-processed systems are generally composed of polymeric diazo resin salts (haUdes or heavy metal), which after photolysis form an insoluble adduct. 

This shows that if is to be negative (work produced) and finite, then must be positive and finite. Thus even for reversible operation, a finite amount of heat must be rejected from the engine to the reservoir at T. ... 

The dyes or dye precursors may be initially diffusible in alkaU, in which case they will be immobilized imagewise, or they may be initially immobile in alkaU and released imagewise to transfer. Positive-working processes produce dye transfer density inversely related to the developed silver density conversely, negative-working processes produce dye transfer density in direct proportion to the developed silver. 

Release by Silver-Assisted Cleavag e. A soluble silver complex formed imagewise in the undeveloped areas of the silver haUde layer may be used to effect a cleavage reaction that releases a dye or a dye precursor. The process yields positive dye transfer images directiy with negative-working emulsions (46). An example is the silver-assisted cleavage of a dye-substituted thiazolidine compound, as shown in equation 7. 

Resists used to define circuit patterns are radiation-sensitive and may be either positive- or negative-working. As a result of the fine lines, there has been movement away from optical Hthography and iato the mid- or deep-uv regioas. Developmeatal work has also beea focused oa electroa beam, x-ray, and ion-beam exposure devices and resists (9,10). 

Since q2>0 and q < 0, and q2 is greater in magnitude than qu the cyclic engine produces a net amount of (negative) work. From our earlier discussion of pressure-volume work, we know that the area enclosed by the cycle in a p-V plot gives the magnitude of this work.p... 

Work done on a system by its surroundings is conventionally taken as negative work done by the system on the surroundings as positive. 

Because the gas was expanding, w is negative (work was being done by the system). 

As mentioned above, the conventional diazonium salts have good optical properties as CEL dyes and negative working sensitizers for the two-layer resist system. However, almost all diazonium salts are stabilized with metal-containing compounds such as zinc chloride, tetrafluoroborate, hexafluoro-antimonate, hexafluoroarsenate, or hexafluorophosphate, which may not be desirable in semiconductor fabrication because of potential device contamination. To alleviate the potential problem, new metal-free materials have been sought for. 

In this paper we report on the use of trifluoro-methanesulfonates (Table 1) of 4-N, N-dimethylamino-benzenediazonium (Dl) and 4-methoxybenzene-diazonium (D2) as CEL dyes, negative working sensitizers, and photoacid generators for chemical amplification resist systems(11). 

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