Prismatic trenches

Positive tone resins based on a photoacid generator and either a random copolymer of tetrahydropyranyl methacrylate and methyl methacrylate [137] or random copolymers of tetrahydropyranyl methacrylate, methyl methacrylate, and t-butyl methacrylate (180) were used for fabrication of 3D microchannel structures [264], Simple placed channels connected to cubic or prismatic trenches, which are open to the surface as well as optical grating structures, comprise a set of several parallel channels placed about 10 pm below the surface with connecting reservoirs on both ends. They were fabricated by positive TP microlithography (Fig. 3.75) [264]. 

Figure 3.75. Three-dimensional microstractures (a) cubic trenches (top Mly developed bottom not fully developed), (b) prismatic trenches (top fully developed bottom not fully developed), and (c) prismatic cavities of 100 pm width, 20 pm length, and 20 pm depth, which are connected by twelve channels of 50 pm length and 4 pm x 4 pm cross section bearing a periodicity of 8 pm and lying 10 pm below the surface. (From Ref. [264] with permission of Wiley-VCH.)...

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