2007 年 32 巻 2 号 p. 329-332
The purposes of this work are to prepare a low density carbon nanofiber (CNF) emitter by a spray spreading method and to investigate the performance of field emission. A sprayed paste was prepared with organic solution of tetrahydrofuran and also with binders of Au paste and Polycarbonate. The used CNF were massively synthesized by a thermal chemical vapor deposition and were burned to eliminate amorphous carbon and catalyst The diameter of the CNF was about 0.1 micro m phi. Two types of CNF were studied with the length of ca. 10-20 micro m (normal-CNF) and ca. 1.5 micro m (cut-CNF). In the normal-CNF emitter the current density at 10 V/micro m. was about 1.4mA/cm2 with an electric field enhancement factor beta of about 1000, while 0.08mA/cm2 with beta of 4500 in the cut-CNF emitter. It was confirmed that the isolated CNF do play an important role as effective emitter sites.
