Method for planarization of wafers with high selectivities
AssigneeUnited Microelectronics Corp.
InventorsShao-Chung Hu, Hsueh-Chung Chen, Shih-Hsun Hsu, Chia-Lin Hsu
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Abstract
A method for planarization of a semiconductor wafer with a high selectivity is describe. The semiconductor wafer has a hard mask, a stop layer disposed on the hard mask, and a barrier layer disposed on the stop layer. The method includes performing a chemical mechanical polishing (CMP) process on the barrier layer so as to expose the stop layer, and removing the stop layer. The polishing selectivity of the barrier layer relative to the stop layer is greater than 50. Since the material of stop layer is different from the material of barrier layer, the high selectivity is easily achieved. Thus, the surface of semiconductor wafer can be highly planarized.
Claims24
A method for planarlzation of a semiconductor wafer, the semiconductor wafer having a hard mask, a stop layer disposed on the hard mask, and a barrier layer disposed on the stop layer, the stop layer being composed of organic polymer material, the method comprising:
- performing a first chemical mechanical polishing (CMP) process on the barrier layer to expose the stop layer;
- and
- removing the stop layer;
- wherein a polishing selectivity for a removal rate the barrier layer is greater than 50 with respect to the stop layer during the first CMP process.
A method for planarization of a semiconductor wafer with a high selectivity, the method comprising:
- providing the semiconductor wafer having a first dielectric layer and a cap layer formed thereon;
- forming a second dielectric layer on the cap layer;
- forming a hard mask on the second dielectric layer;
- forming a stop layer on the hard mask;
- forming a barrier layer on the stop layer;
- forming a conductive layer on the barrier layer;
- performing a first chemical mechanical polishing (CMP) process on the conductive layer to expose the barrier layer;
- performing a second chemical mechanical polishing (CMP) process on the barrier layer to expose the stop layer;
- and
- removing the stop layer;
- wherein a polishing selectivity for a removal rate of the barrier layer is greater than 50 with respect to the stop layer during the second CMP process.
Dependencies are inferred from the claim text.