Carbon　nanofilm　and　nanodots　were　grown　by　plasma-enhanced　hot　filament　chemical　vapor　deposition　using　methane,　hydrogen　and　nitrogen　as　the　reactive　gases.　The　results　of　field　emission　scanning　electron　microscopy,　micro-Raman　spectroscopy　and　X-ray　photoelectron　spectroscopy　indicate　that　the　amorphous　carbon　nanofilm　and　nanodots　are　formed　without　and　with　nitrogen,　respectively.　The　formation　of　carbon　nanofilm　and　nanodots　is　the　consequence　of　different　sputtering-etching　effects.　The　photoluminescence　(PL)　of　carbon　nanofilm　and　nanodots　was　studied　in　a　SPEX　1403　Ramalog　system　using　a　325　nm　He-Cd　laser　as　an　excitation　source　and　the　PL　spectra　show　the　PL　bands　centered　at　about　411　and　513　nm　for　the　carbon　nanofilm　and　405　and　504　nm　for　the　carbon　nanodots.　Simultaneously,　the　PL　results　also　indicate　that　the　intensity　of　PL　bands　of　carbon　nanofilm　is　lower　than　that　of　carbon　nanodots.　The　generation　of　different　PL　bands　was　interpreted　by　the　transition　mechanism.　The　difference　in　the　intensity　of　PL　bands　is　related　to　the　size　of　carbon　nanodots.　The　electron　field　emission　(EFE)　characteristics　of　carbon　nanofilm　and　nanodots　were　investigated　in　a　high-vacuum　system.　The　results　show　that　Fowler-Nordhelm　curves　are　composed　of　two　or　three　straight　lines　and　the　carbon　nanofilm　can　emit　a　high　current　density,　which　originate　from　the　diversification　of　carbon　nanodots.　The　difference　in　the　EFE　results　of　carbon　nanofilm　and　nanodots　is　associated　to　the　size　and　number　of　carbon　nanodots.　These　results　can　enrich　our　knowledge　about　carbon-based　nanomaterials　and　are　important　to　fabricate　the　carbon-based　solid　nanodevices　in　the　field　of　optoelectronics.　(C)　2014　Elsevier　Ltd.　All　rights　reserved.