Development of a novel air-back wafer carrier with an integrated endpoint detector for copper CMP application

This study presents the development of a novel air-back polishing carrier with an integrated Linear Variable Differential Transformer Endpoint Detector (LVDT EPD). In the course of this study, uniformity evaluation was performed on blanket PETEOS oxide and blanket copper wafers and dishing/erosion multi-step polish on patterned wafers. Employment of an air-back polishing carrier resulted in non-uniformity <3% 1σ. The LVDT EPD showed an excellent S/N ratio. The combination of LVDT EPD and air-back polishing carrier significantly enhanced the process performance in Cu CMP