Photobleachable resist system

Application to the two-layer resist system. Photobleachable resist systems that have a strong absorption before exposure and that bleach completely upon UV exposure alleviate the light reflection from the substrate. A photobleachable resist system formed by means of the doping process liras reported in our previous paper (9). This resist system consists of two layers in which a diazonium salt is distributed in both the top and bottom layers. When exposed to i-line, the diazonium salt in... 

Diazonium salts are also useful as a photosensitive material in a photobleachable two-layer resist system based on a doping process (10). High-resolution resist patterns were obtained using this two-layer resist scheme and an i-line reduction projection aligner. 

One way to increase resolution is by use of a photobleachable chemical system (applied as a thin polymer film on top of a conventional resist) whose response to light is strongly nonlinear (4-8). 

Notably, the patterning of thick layers, commonly consisting of multiple coats of spun-cast polymer, necessitates a high transparency of the resist system. Therefore, care has to be taken that the maximum exposure depth exceeds the thickness of the layer. In special cases, the initiator/sensitizer is photobleached, thus causing the penetration depth of the incident fight to increase during exposure. 

The remarkable resistance of GFPs to photobleaching, i.e., to a complete destruction of their chromophore conjugated system upon illumination, gives room to a wide... 

In a later collaboration with the Fleming lab, the rate constants of the energy transfer events were measured using time-resolved spectroscopic methods. In a subsequent report, Francis and coworkersalso showed that the TMV-based systems can achieve energy transfer in multiple dimensions. This feature of the self-assembled system provides many redundant energy transfer pathways that ultimately impart an improved resistance to photobleaching damage than can be achieved in low-dimensional systems. 

A second major development in photolithographic chemistry has been that of image enhancement by photobleaching. A number of different variations on this theme exist the primary ones are contrast enhancement (C L) (5), photochemical image enhancement (PIE) (6-9), and built-on mask (BOM) (10). CEL was the first of these to appear in this process a polymer containing a bleachable dye is spun on top of the resist, and both are exposed together. We originated the PIE system shortly thereafter it likewise uses a top layer of... 

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