A　high-pulse-energy　femtosecond　pulsed　Ti:sapphire　laser　was　employed　to　perform　laser　drilling　of　2.4-mm-thick　thermal　barrier　coated　In718.　The　influences　of　polarization　on　hole　profile　and　morphology　of　periodic　structures　on　the　sidewall　of　drilled　holes　were　explored.　Based　on　Fresnel　formula,　combined　with　the　effects　of　multiple　reflections　and　energy-trapping,　a　comprehensive　analysis　of　the　effect　of　polarization　on　polarization　removal　was　proposed.　The　microstructures　on　the　sidewall　of　drilled　holes　for　different　layers　under　different　polarizations　were　compared.　The　fabricated　structures　on　the　thermal　barrier　coating　(TBC)　layer　showed　a　strong　dependence　on　the　polarization　state　of　the　laser　beam.　The　structures　with　ball-like　profile　were　generated　under　circular　polarization　while　pine　needle-like　periodic　structures　were　produced　under　linear　polarization.　However,　for　both　the　bond　coat　and　substrate　layers,　the　microstructures　of　the　sidewall　were　independent　of　the　polarization　state　of　the　laser　beam.　For　TBC　layer　the　interaction　between　the　resonance　of　charge　carriers　and　the　second　harmonic　of　the　surface　contributed　to　a　corrugated　structure　in　harmony　with　the　polarization　state.　Thereinto,　the　charge　carriers　may　remember　the　polarization　state　of　the　light　beam　and　maintain　this　information　because　of　the　low　mobility.　©　2020　Elsevier　B.V.