Inductively Coupled Plasma Etching of Pt/Ti Electrodes in Cl-Based Plasma

Abstract:

Dry etching of Pt/Ti film was carried out using Cl₂/Ar plasmas in an inductively coupled plasma (ICP) reactor. The influence of the various process parameters, such as RIE power, ICP power and Cl₂/Ar gas mixing ratio, on the etch rate and selectivity of photoresist to Pt/Ti film were investigated systematically and optimized. It was revealed that the etch rate and the selectivity strongly depended on the key process parameters. The etch rate was found to increase dramatically with increasing of RIE power and ICP power. But by changing the ratio of Cl₂ to the total gas, the maximum etch rate could be obtained at the proper ratio of 20%. The results also indicated too low or too high RIE power and the Cl₂ ratio was detrimental to the selectivity. The optimized parameters of Pt/Ti dry etching for high etch rate and low selectivity of photoresist to Pt/Ti were obtained to be pressure: 10mT, RF power: 250W, ICP power: 0W, Cl₂: 8sccm (standard cubic centimeters per minute), Ar: 32sccm.

• Periodical: Advanced Materials Research (Volume 721)
• Pages: 346-349
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.721.346
• Online since: July 2013
• Authors: Zhi Qin Zhong, Cheng Tao Yang, Guo Jun Zhang, Shu Ya Wang, Li Ping Dai
• Keywords: Dry Etching, Etch Rate, Inductively Coupled Plasma, Pt/Ti Film, Selectivity

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