Low Temperature Si/Si Wafer Direct Bonding by Plasma Activated Method

摘要：

　　Manufacturing and integration of MEMS devices by wafer bonding often lead to problems generated by thermal properties of materials.This paper presents a low temperature wafer direct bonding process assisted by O2 plasma.The silicon wafers were treated with wet chemical cleaning and subsequently activated by O2 plasma in the etch element of sputtering system.The activated wafers were brought into contact in the bonder and followed by annealing in N2 atmosphere for several hours.IR imaging system was used to detect the bonding defects and razor blade test was carried out to determine the surface energy.The bonding yield reach 90-95%,and the surface energy is achieved 1.76J/m2 when the bonded wafers is annealed at 350℃ in N2 atmosphere for 2 hours.Void formation was systematically observed and the eliminate methods were proposed.The size and density of voids greatly depend on the annealing temperature.Pulling test reveals that the bonding strength is more than 11MPa.This low temperature wafer direct bonding process provides a high efficiency and reliable method for 3D device integration,system on chip and MEMS packaging.

关键词： low temperature wafer direct bonding O2 plasma activation surface energy void formation

作者: Dongling Li Zhengguo Shang Zhiyu Wen Shengqiang Wang

作者单位: National Key Laboratory of Fundamental Science of Novel Micro/Nano Device and SystemTechnology, Chongqing University, Chongqing 400044, P.R.China;Microsystem Research Center, Chongqing University, Chongqing 400044, P.R.China

会议类型: 国际会议

会议名称: 中国微米纳米技术学会第14届学术年会、第3届国际年会暨第6届微米纳米技术“创新与产业化国际研讨与展览会(CSMNT2012 & ICMAN2012)

会议地点: 杭州

会议语种:英文

页码: 1-7

在线出版日期: 2012-11-04（万方平台首次上网日期，不代表论文的发表时间）