Three-dimensional lithographic

The three-dimensional circuit elements are fabricated by a series of processes collectively known as lithography . The pattern is first generated in a polymeric film on a device wafer and this pattern is then transferred via etching, into the underlying thin film. The purpose of this book is to review the theory, materials, and processes that are used in the lithographic process. This book is intended to be a tutorial and not a comprehensive review. Each chapter contains many references to which the reader can refer for more detail on any specific aspect of microlithography. 

This imposes a limitation on the sensitivity of the resist, i.e., it is necessary to design a resist that will react sufficiently to to produce a lithographically useful, three-dimensional relief image. Now let us consider the four subsystems and their limitations. 

The goal of any lithographic technology is to produce a three-dimensional relief image whose size and fidelity match, as closely as possible, that of the image in the mask or the serial exposure beam. As we discussed in Chapter 2, pattern definition in a resist consists of two distinct steps ... 

Dinca and colleagues (2008) have combined fibril self-assembly, lithographic features, and covalent and noncovalent binding to create three-dimensional patterned fibrillar structures that could be used in electronics or tissue engineering. Images of these structures, which are described as fibril bridges, are shown in Figure 15. 

Lithographic methods are able to generate very uniform nanoparticle arrays and can be used to monitor the preparation process. In combination with additional techniques, even various three-dimensionally shaped structures can be formed (see, e.g., [16]). However, lithographic methods suffer from the limitation that the small interparticle spacings required for huge electromagnetic enhancement are not technically feasible. 

Assembling fiuorophore-metal nanoparticle superstructures as a two- or three-dimensional architecture provides routes to design novel materials with tailored electrical [99], optical [100-102], lithographic [63, 103-107], sensing [18, 108-112],... 

The three-dimensional electrochemical cell is a hypothetical device that illustrates how some of the advances in microscale and nanoscale electrochemistry over the past two decades may be applied to its construction (Figure 6.1). The three-dimensional electrochemical cell is a conventional battery in the sense that it has a cathode and anode, but they are configured in an interpenetrating array with electrodes anywhere from micron dimensions if they are prepared using lithographic techniques down to the nanometer scale. 

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