High-contrast developers characteristics

This system has been reported to show good photosensitivity (—100 mJ/cm2 in the 230-300 nm range) with extremely high contrast. Values of 7 > 5 were observed, compared to 2 for conventional systems. Chandross et al. believe the high contrast stems from the unusual dissolution characteristics of the resist in that the basic "developer" appears only to "prime" the irradiated regions for subsequent development in the aqueous rinse. The resist formulation is essentially aliphatic in nature and would be expected to be less stable to dry etching environments than the aromatic-based novolac resin materials. 

Currently, to develop more highly functionalized LC devices, intensive studies are being carried out on electrically controllable polymer/LC composite films with such advantageous features as high electric field response, high contrast, and wide viewing angle, as well as reverse-mode and haze-free characteristics. 96-100 ... 

Figure 8.11 Voltage versus deflection characteristics. (Used with pertnission from S.A. Cornelissen, P.A. Bierden, andT.G. Bifano, Development of a 4096 element MEMS continuous membrane deformable mirror for high contrast astronomical imaging, Proc. SPIE 6306, p. 630606-1 [2006].) [21]. See color...

By introducing these methods, a high contrast VA-type LCD with maximum viewing angle characteristics has been developed that is now used in standard large TVs. 

Thus, it is still uncommon to test QSAR models (characterized by a reasonably high q ) for their ability to predict accurately biological activities of compounds not included in the training set. In contrast to such expectations, it has been shown that if a test set with known values of biological activities is available for prediction, there exists no correlation between the LOO cross-validated and the correlation coefficient between the predicted and observed activities for the test set (Figure 16.1). In our experience [17, 28], this phenomenon is characteristic of many datasets and is independent of the descriptor types and optimization techniques used to develop training set models. In a recent review, we emphasized the importance of external validation in developing reliable models [18]. 

Figure 1 shows the exposure characteristics of atactic and isotactic poly(a,a-dimethylbenzyl methacrylate) resists with CH3ONa development together with those of the poly (methyl methacrylate) resist with MIBK/IPA development. Poly(a,a-dimethylbenzyl methacrylate) s showed high sensitivity and very good contrast between exposed and unexposed areas. The atactic polymer with alkaline development was improved in the sensitivity and 7-value by a factor of more than three over poly(methyl methacrylate) with MIBK/IPA development. 

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