Scandia　doped　tungsten　matrix　dispenser　cathodes　were　manufactured　using　scandia　doped　tungsten　powder　prepared　by　mechanical　mixing,　liquid-solid　doping　and　a　spray　drying　method.　It　is　found　the　macrostructure　of　the　cathode　depended　on　the　powder　preparation　method.　The　cathode　prepared　using　the　powder　prepared　by　spray　drying　method　had　a　homogenous　and　porous　matrix　characterized　with　grains　with　a　diameter　of　less　than　1　pm　and　with　many　nanoparticles　distributing　uniformly　around　these　grains.　The　cathode　with　submicron　structure　and　uniform　distribution　of　scandia　exhibited　good　emission　uniformity.　The　emission　uniformity　Delta　J/J　of　the　cathode　prepared　by　spray　drying　method　was　0.17,　about　6　times　lower　than　that　of　the　cathode　prepared　by　mechanical　mixing　method.　The　calculation　results　showed　that　the　nanoparticles　led　to　electric　field　enhancement.　A　Ba-Sc-O　multilayer　on　the　cathode　surface　and　nanoparticles　distributing　mainly　on　W　grains　contributed　to　the　emission　property　of　the　cathode.　(C)　2013　Elsevier　Ltd.　All　rights　reserved.