Semiconducting　microbelts　are　key　components　of　the　thermoelectric　micro-devices,　and　their　electrical　transport　properties　play　significant　roles　in　determining　the　thermoelectric　performance.　Here,　we　report　heavily　Cu-doped　single-crystal　SnSe　microbelts　as　potential　candidates　used　in　thermoelectric　microdevices,　fabricated　by　a　facile　solvothermal　route.　The　considerable　Cu-doping　concentration　of　similar　to　11.8%　up　to　the　solubility　contributes　to　a　high　electrical　conductivity　of　similar　to　416.6　S　m(-1)　at　room　temperature,　improved　by　one　order　of　magnitude　compared　with　pure　SnSe　(38.0　S　m(-1)).　Meanwhile,　after　loading　similar　to　1%　compressive　strain　and　laser　radiation,　the　electrical　conductivity　can　be　further　improved　to　similar　to　601.9　S　m(-1)　and　similar　to　589.2　S　m(-1),　respectively,　indicating　great　potentials　for　applying　to　thermoelectric　microdevices.　Comprehensive　structural　and　compositional　characterizations　indicate　that　the　Cu+　doping　state　provides　more　hole　carriers　into　the　system,　contributing　to　the　outstanding　electrical　conductivity.　Calculations　based　on　first-principle　density　functional　theory　reveal　that　the　heavily　doped　Cu　lowers　the　Fermi　level　down　into　the　valence　bands,　generating　holes,　and　the　1%　strain　can　further　reduce　the　bandgap,　strengthening　the　ability　to　release　holes,　and,　in　turn,　leading　to　such　an　excellent　electrical　transport　performance.　This　study　fills　the　gaps　of　finding　novel　materials　as　potential　candidates　used　in　the　thermoelectric　microdevices　and　provides　new　ideas　for　micro/nanoscale　thermoelectric　material　design.　(C)　2020　Elsevier　Ltd.　All　rights　reserved.