The memory device fabrication system has already applied a lot of CMP processes for various purposes. As memory device integration increased, more CMP processes are needed. Typically CMP process can be divided into Oxide CMP, W CMP, Cu CMP, etc. These CMP technologies are important solution that can be used as memory mass production technologies develop.

3D NAND devices are being highlighted and developed as a way increase the integration method, due to the nature of its structures, 3D NAND device needs various CMP processes. In particular, the number of W CMP processes has several times multiplied over than 2D devices. In addition, more W CMP processes will be required as the device's generation evolves. However, a period of change pad, in W CMP process, is shorter than other CMP processes. Hence, it will lead to lower productivity and higher costs in fabrication system. Productivity and cost in mass production system are very important competitiveness. Thus, it is necessary to make improvements to the same level as others. There are several reasons why the W CMP process has a shorter pad replacement cycle in the 3D NAND device. One of the causes is that slurry directly or indirectly affects the wear of diamonds on conditioner. As a result, ability of polishing is decrease, pad and conditioner have no choice but to replace.

In this study, we figured out which components of W slurry are being applied by W CMP in the 3D device and how they affect the wear of diamonds. And we have carried out experimental study to improve it and we will discuss the results.