A　single　layer　of　tightly　arranged　silicon　oxide　nanospheres　was　formed　on　GaAs　substrate　by　gas-liquid　interface　self-assembly　method.　The　silicon　oxide　nanospheres　were　used　as　the　etching　barrier　layer,　and　the　GaAs　nanocolumn　array　was　prepared　by　dry　etching　with　inductively　coupled　plasma　(ICP)　of　SiCl4/Ar　gas.　The　results　show　that　the　morphology　of　GaAs　nanocolumns　can　be　optimized　by　controlling　the　technological　conditions　in　the　preparation　process,　such　as　reaction　gas　flow,　sample　chamber　pressure　and　RF　power.　The　optimal　technological　parameters　are　obtained,　and　the　GaAs　nanocolumn　arrays　with　smooth　and　steep　sidewalls　are　prepared.　©　2023　SPIE.