Wafer　grinding　is　a　key　process　for　integrated　circuit　chip　packaging.　The　air　spindle,　the　core　component　of　thinning　equipment,　directly　affects　the　TTV　and　roughness　of　wafer　grinding.　In　view　of　the　requirement　of　large　and　stable　wafer　grinding　force,　this　paper　proposes　a　new　type　of　air　spindle　structure　with　large　bearing　capacity　and　high　stiffness.　The　working　principle　of　the　new　type　of　air　spindle　is　introduced,　and　the　analytical　formulas　of　the　bearing　characteristics　of　the　radial　bearing　and　the　thrust　bearing　are　deduced　by　using　the　volume　flow　method.　relationship　between　parameters.　Based　on　the　Reynolds　equation　and　the　NS　equation,　a　numerical　model　of　the　orifice　hydrodynamics　was　established,　and　the　air　pressure　distribution　of　the　air　film　under　the　no-load　condition　of　the　main　shaft　was　obtained　by　the　finite　element　method.　Through　the　comparison　of　the　bearing　capacity,　the　analytical　method　and　the　finite　element　method　are　in　good　agreement,　and　the　bearing　capacity　and　stiffness　of　the　designed　air-floating　spindle　can　meet　the　requirements　of　wafer　grinding.　©　2022　IEEE.