Carbon　nanotips　were　grown　from　carbon　film　deposited　on　silicon　substrate　by　plasma-enhanced　hot　filament　chemical　vapor　deposition.　The　carbon　film　and　carbon　nanotips　were　investigated　by　scanning　electron　microscopy　and　micro-Raman　spectrometry,　respectively.　The　results　indicate　that　the　carbon　film　is　composed　of　amorphous　carbon　and　the　carbon　nanotips　are　characteristic　of　nanographite,　and　their　formation　and　shapes　depend　on　ion　bombardment　strongly.　Simultaneously,　the　number　of　forming　the　carbon　nanotips　is　increased　by　the　ion　bombardment.　Because　there　are　ion　deposition　and　sputtering-etching　in　the　process　of　growing　of　the　carbon　nanotips,　the　theory　related　to　ion　deposition　and　sputtering　was　used　to　obtain　their　formation　condition　and　analyze　effects　of　the　ion　bombardment　on　their　shapes　and　the　number　of　forming　them.　(C)　2007　Elsevier　B.V.　All　rights　reserved.