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Resistive random access memory has attracted enormous attention as next generation high density nonvolatile memory for flash memory, due to its low voltage operation, high programming speed, and simple fabrication. And Chemical mechanical planarization technology of the novel memory materials is also the necessary work for its application in RRAM devices, especially for TiO 2 、 NiO and VOx films which are the focused RRAM materials recently. In this paper, CMP of VOx films was investigated firstly, and the effect of slurry pH on MRR and surface roughness was discussed. MRR results show that high polishing rates can be observed with low pH (acidic slurry) and high pH (alkaline slurry), which are more than 250 nm/min. However, lower surface roughness can be achieved only when alkaline slurry was used (0.12 nm vs 2.6 nm). In conclusion, the alkaline slurry with silica abrasives is the optimum candidate for CMP of VOx films.

Titanium dioxide (TiO 2 ) has shown a great potential to be used in resistive random access memory, capacitor, solar cell and sensor. However, the surface topography as-deposited TiO 2 film cannot meet the requirement of IC. Therefore, TiO 2 film must be flattened before being applied into semiconductor devices. In this paper, chemical mechanical polishing (CMP) was used for polishing TiO 2 film. We studied the effect of slurry PH of polishing from the viewpoint of chemical we found the removal rate with acidic slurry is lower than the removal rate obtained by alkali slurry. The effect of the process parameter such as down force, platen rotation rate were also studied in detail and found the removal rate still exist when there is no pressure and velocity, hence Preston equation was slightly modified. Finally, the surface roughness was reduced from 36Å to 1.2Å, and the removal rate was up to 38.2nm/min.

Because of its good properties, diamond can be used as protective film of optical components, optical window materials and radiator materials of high power optoelectronic components. But its rough surface has been an obstacle for widespread application. In this paper, etching of diamond films by ICP (Inductively Coupled Plasma) oxygen plasma which was used to improve the surface of the diamond films. After evaluating etch rates under different O 2 /Ar conditions, the etch mechanism is investigated. The results show that the surface roughness is reduced after etching. Etching rate increases with higher O 2 /Ar ratio. At the same time, when etching with a high O 2 /Ar ratio, the surface roughness is low. In conclusion, O 2 and Ar plasmas, especially O 2 plasmas, have a significant effect on etching of diamond films.