Study on the removal rate and electrochemical corrosion of titanium in chemical mechanical polishing

Titanium (Ti), known for its high mechanical strength and excellent corrosion resistance, is commonly used in high-precision devices such as MEMS and integrated circuits. Consequently, the chemical mechanical polishing (CMP) of the titanium barrier layer plays a crucial role in the fabrication procedure. Nevertheless, owing to the distinctive physical and chemical characteristics of titanium, attaining a high removal rate for this material poses a significant challenge. The effect of Diethylenetriamine penta methylene phosphonic acid (DTPMP) as a complexing agent on the chemical mechanical polishing of titanium barrier layer was studied in this paper. The removal mechanisms of titanium were examined through polishing experiments and the corrosion current of titanium increases in the electrochemical experiments. When the concentration of DTPMP is 15mM, the removal rate of Ti is 960Å/min.