Process of planarizing a wafer with a large step height and/or surface area features

A process of planarizing a wafer, comprising:

• providing the wafer comprising a first layer and a second layer vertically on the first layer and defined into a first region and a second region laterally abutting the first region;
• performing an etching process to remove the second layer in the first region;
• forming a third layer conformally covering the first layer and the second layer;
• forming a blanket stop layer conformally on the third layer;
• performing a first chemical mechanical polishing process to remove the blanket stop layer atop the third layer in the second region;
• performing a second chemical mechanical polishing process to planarize the wafer using the second layer or the blanket stop layer as a stop layer;
• and
• stripping the remaining blanket stop layer.

A process of planarizing a wafer, comprising:

• providing the wafer comprising a first layer and a second layer vertically on the first layer and defined into a first region and a second region laterally abutting the first region;
• etching the wafer to remove the second layer in the first region;
• forming a third layer conformally covering the first layer and the second layer;
• forming a blanket stop layer conformally on the third layer;
• performing a first chemical mechanical polishing process to remove the blanket stop layer atop the third layer in the second region;
• performing a selective dry etch process to remove the third layer in the second region selective to the blanket stop layer and the second layer in the second region;
• and
• performing a second chemical mechanical polishing process to planarize a surface topography of the wafer using a non-selective slurry.