FABRICATION OF BIOLOGICALLY BASED MICROSTRUCTURE COMPOSITES FOR VACUUM FIELD-EMISSION

A multidisciplinary approach to the fabrication of biologically based microstructure composites for vacuum field emission is described. Diacetylenic lipid 1,2-bis(10, 12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC, PC) was self-assembled to form hollow cylindrical tubules approximately 0.5 mum in average diameter and 50-80 mum long. Following the deposition of nickel on the inner and outer tubule sur-faces by an electroless plating method, the nickel-plated tubules were magnetically aligned in an epoxy matrix to form a composite material. Subsequent selective removal of the matrix provided a composite base template of oriented exposed tubules. The tubule template was coated with a thin sputtered gold film to provide the surface electrical contact. The resultant microstructures demonstrated vacuum field emission of current I > 10 muA at relatively low applied macroscopic electric fields (about 60-150 kV cm-1).