In　this　study,　we　present　an　approach　to　manufacture　individual　and　array-type　carbon　nanotubes　in　a　transmission　electron　microscope.　Semiconductor　nanowires　are　used　as　templates　to　form　a　coreeshell　structure　by　depositing　uniform　amorphous　carbon　layers　around　the　nanowires　using　electron-beam　induced　deposition.　Joule　heating　produced　by　an　applied　external　voltage　melts　the　nanowires　and　crystallizes　the　amorphous　carbon　layer　into　nanotubes　within　a　commercial　in-situ　scanning　tunnelling　microscope-transmission　electron　microscope　probing　system.　Using　this　approach,　carbon　nanotubes　with　well　controlled　wall　thicknesses,　diameters　and　lengths　have　been　fabricated.　In-situ　measurements　of　electrical　properties　reveal　that　the　resultant　carbon　nanotubes　have　a　semiconducting　resistivity.　By　the　demonstration　of　producing　a　nanotube　array,　this　proof-of-concept　approach　opens　a　new　pathway　to　fabricate　high-performance　carbon　nanotube　arrays　with　controllable　morphology　for　practical　applications.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.