In　order　to　adapt　to　the　trend　of　ultra-high　resolution　and　extremely　fine　wiring　of　LTPS　TFT　LCD　display,　reduce　the　yield　loss　generated　by　via　etching　process　of　LTPS　TFT　interlayer　dielectric,　and　improve　the　production　quality,　the　process　optimization　of　via　etching　process　of　LTPS　TFT　interlayer　dielectric　was　investigated.　The　experiments　were　based　on　dry　etching　as　the　main　etching　step　assisted　with　wet　etching.　It　not　only　conbined　with　the　excellent　control　of　profile　and　feature　size　of　dry　etching　but　also　got　high　etching　selectivity　of　wet　etching.　The　experiments　also　aimed　at　reducing　the　damage　and　defects　reduced　by　dry　etching　and　avoiding　pollution　of　the　hole　surface　by　etching　by-products.　Experimental　results　indicated　that　dry　etching　assisted　with　wet　etching　basically　solved　the　problems　of　over　etching　and　etching　residual,　reduced　the　yield　loss　of　via　etching　defect　rate　by　73%.　And　contact　resistance　reduced　by　about　90%,　ON-state　drain　current　raised　15%　of　the　dry　etching.　Therefore　dry　etching　assisted　with　wet　etching　is　an　innovative　method　to　optimize　the　via　etching　process　and　promote　product　performance.　©　2016,　Science　Press.　All　rights　reserved.