Submicron fabrication

As shown in Figure 8, a high resolution pattern is obtained by reducing the resist thickness in 1LR system, but in VLSI fabrication process resist thickness more than 1.0 is needed to planarize the topographic surface, so that 2LR system is more useful for submicron fabrication than 1LR system. 

When Cu was electrochemically deposited onto the GaAs surface part of which was modified by the AFM tip, Cu was deposited selectively on the scratched portion. This result may lead to a novel technique for the submicron fabrication. 

For finer feature sizes, the interconnection delay plays a more important role, due to more complex designs fitting into one chip and the higher system performance required. Redundant operator allocation becomes a feasible solution due to the smaller area of operators. Our predictions show the interconnection delays will become dominant when submicron fabrication process are used. 

Determinants of baghouse performance include the fabric chosen, the cleaning frequency and methods, and the particulate characteristics. Fabrics can be chosen which will intercept a greater fraction of particulate and some fabrics are coated with a membrane with very fine openings for enhanced removal of submicron particulate. Such fabrics tend to be more expensive. 

Fabricate submicron spherical core of material X responsive to one class of vapors... 

Fabrication of composite colloidal spheres involves two steps submicron particles are fabricated from a material preferentially responsive to one class of chemicals followed by a step in which the submicron spheres are coated with a shell that is preferentially responsive to another class of chemicals. A colloidal crystal array is subsequently self-assembled into a 3D ordered film. 

As an example of composite core/shell submicron particles, we made colloidal spheres with a polystyrene core and a silica shell. The polar vapors preferentially affect the silica shell of the composite nanospheres by sorbing into the mesoscale pores of the shell surface. This vapor sorption follows two mechanisms physical adsorption and capillary condensation of condensable vapors17. Similar vapor adsorption mechanisms have been observed in porous silicon20 and colloidal crystal films fabricated from silica submicron particles32, however, with lack of selectivity in vapor response. The nonpolar vapors preferentially affect the properties of the polystyrene core. Sorption of vapors of good solvents for a glassy polymer leads to the increase in polymer free volume and polymer plasticization32. 

Fig. 4.2 TEM images of fabricated nanoparticles, (a) Isolated composite core/shell submicron particles, (b) Hollow silica submicron particles prepared by removing the polystyrene core to demonstrate the high quality of the formed sol gel shell of the composite nanospheres employed to prepare sensing colloidal crystal films...

As a simple and practical alternative to coated microspheres, submicron particles of pendant amine-functionalized PPE 39 could be fabricated by phase... 

Electron beam resists to be used in direct wafer writing for submicron devices need significant improvement in sensitivity, resolution and dry etching durability. Multilayer resist (MLR) systems are now regarded as the most important technology to perform practical submicron lithography for VLSI fabrication (1-3). Many advantages in MLR compared with one layer resists (1LR) are listed here ... 

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