In this study, we evaluated the dilute HF (DHF) cleaning to reduce residual defects made by metal CMP process. The purpose of this test is to observe the existence of barrier metal damage during DHF cleaning on condition that it should not affect metal thin film reliability, so we will get rid of slurry residual particles as a main defect of the metal CMP process for the better yield. Slurry residual particles occurred 2 ea at base line and less than 1 ea at other split conditions by HF application. In-line defect data showed us that slurry residual particles are removed by DHF application. The HF rinse significantly reduced metal contamination levels and surface roughness, too. Metal contaminations more decreased in proportion to the increase of DHF quantity. Regardless of split condition, it wasn't presented any barrier metal damage. In addition, it was observed that the metal plug recess difference of each wafer is only a maximum of 14 A in the Center area. The best effect by additional oxide loss was concluded when Dilute HF condition is 10″.
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