In　this　study,　the　indium　tin　oxide　(ITO)　was　etched　by　an　inductively　coupled　plasma　(ICP)　etcher　using　Cl2/C2H4/Ar　as　the　etching　gases.　The　etch　rates　were　studied　as　a　function　of　RF　power,　inductively　coupled　plasma　(ICP)　source　power,　working　pressure　and　gas　mixing　ratio.　We　found　that　the　RF　Power　plays　a　dominant　role　in　the　elevation　of　the　etch　rates,　which　indicates　that　the　ITO　etching　in　this　study　is　a　physical　mechanism　dominated　etching.　The　state　of　the　photoresist　(PR)　was　observed　after　each　experiment.　As　expected,　the　high　power,　which　generally　leads　to　a　high　etch　rate,　would　distort　the　PR　mask,　resulting　in　a　bad　etched　profile　of　the　sample.　Through　research,　we　got　a　relatively　high　etch　rate　(∼　200nm/min)　with　the　shape　of　PR　mask　remain　undistorted.　The　profile,　which　includes　the　morphology　of　the　film　sidewall　and　surface　after　the　etching　process,　was　sensitive　to　the　gas　mixing　ratio.　We　adjusted　the　gas　mixing　ratio,　and　observed　the　profile　using　a　scanning　electron　microscope　(SEM),　then　optimal　morphology　was　get　as　the　Cl2/C2H4/Ar　at　the　value　of　30sccm/7sccm/50sccm.　©　2009　SPIE-OSA-IEEE.