公开(公告)号：WO0035627A2

公开(公告)日：2000-06-22

申请号：PCT/US9930112

申请日：1999-12-16

Applicant: SPEEDFAM IPEC CORP

Inventor： HOLLAND KAREY ,  ZUTSHI AJOY ,  DAI FEN ,  GOTKIS YEHIEL ,  YANG C JERRY ,  SCHEY DENNIS ,  MITCHEL FRED ,  YANG LIN

IPC: B24B37/04 ,  H01L21/304 ,  H01L21/321 ,  H01L21/768 ,  B24B

CPC classification number: B24B37/04 ,  H01L21/3212 ,  H01L21/7684

Abstract: A multi-step CMP system is used to polish a wafer to form metal interconnects in a dielectric layer upon which barrier and metal layers have been formed. A first polish removes an upper portion of the metal layer using a first slurry and a first set of polishing parameters, leaving residual metal within the dielectric layer to serve as the metal interconnects. A second polish of the wafer on the same platen and polishing pad removes portions of the barrier layer using a second slurry under a second set of polishing parameters. The second polish clears the barrier layer from the upper surface of the dielectric layer, thereby forming the metal interconnect. To reduce dishing and dielectric erosion, the second slurry is selected so that the barrier layer is removed at a faster rate than the residual metal within the dielectric layer. A cleaning step may be optionally performed between the first and second polishes. Further, the first polish may include a soft landing step to further reduce dishing and dielectric erosion. Alternatively, the first polish may be used to remove portions of the metal and barrier layers, leaving residual metal in the dielectric layer to serve as the metal interconnect. A second polish using a dielectric slurry is then performed to reduce microscratches.

Abstract translation: 使用多步CMP系统来抛光晶片以在形成有阻挡层和金属层的电介质层中形成金属互连。 第一抛光剂使用第一浆料和第一组抛光参数去除金属层的上部，留下介电层内的残余金属用作金属互连。 在同一压板和抛光垫上的晶片的第二次抛光在第二组抛光参数下使用第二浆料去除部分阻挡层。 第二抛光从电介质层的上表面清除阻挡层，从而形成金属互连。 为了减少凹陷和电介质侵蚀，选择第二浆料，使得以比介电层内的残余金属更快的速率去除阻挡层。 可以可选地在第一和第二抛光剂之间执行清洁步骤。 此外，第一抛光剂可以包括软着陆步骤以进一步减少凹陷和电介质侵蚀。 或者，可以使用第一抛光剂去除金属和阻挡层的部分，在电介质层中留下残余金属用作金属互连。 然后使用电介质浆料进行第二次抛光，以减少微细纹。