Ultra-high current density carbon nanotube field emitter structure on three-dimensional micro-channeled copper

摘要

High-current field emitter with extended stability has been focus of many researchers, which can be fulfilled by application of engineered nanomaterials and beneficial design. In the present research, such a field emitter is designed and fabricated, involving growth of interface controlled carbon nanotubes along micro-channels of 3-dimensional copper template. The emitter offers very high emission current density (270 mA/cm~2, peak), low turn-on field (1.1V/μm), moderate threshold field (1.69 V/μn), emission stability for extended operation, and excellent resistance to structural damage. Higher conductivity of Cu, lower interfacial resistance, strong interfacial bonding, and unique 3-dimensional design leads to such 23-27 times higher current density, providing a potential approach to field emission devices.