Direct bonding of lithium tantalate to silicon at room temperature by using a self-sputtered bonding method
Direct bonding of lithium tantalate to silicon at room temperature by using a self-sputtered bonding method
复制标题
采用自溅射键合方法在室温下直接键合钽酸锂与硅
DOI：
10.7567/1347-4065/ab0ffd
复制
发表时间：
2019
影响因子：
1.5
通讯作者：
J. Utsumi
中科院分区：
文献类型：
--
作者：
J. Utsumi
将压电基片与低热膨胀系数的支撑基片直接键合是制造温度补偿表面声波器件所采用的一种方法。我们提出了一种在室温下将钽酸锂（LiTaO₃）晶片与硅（Si）晶片键合的新技术。硅晶片的表面通过氩等离子体进行蚀刻和活化，同时在高真空下在钽酸锂晶片表面沉积一层硅薄膜。然后立即将这两个晶片接触。一种裂纹张开方法和拉伸测试证实，晶片之间的键合比表面活化键合方法所产生的键合更强。通过透射电子显微镜在键合界面观察到一个约8纳米厚的非晶中间层。我们提出的技术对于热膨胀系数差异较大的不同材料在室温下的直接键合是有用的。
The direct bonding of a piezoelectric substrate to a support substrate with a low coefficient of thermal expansion is a method used in fabricating temperature-compensating surface-acoustic-wave devices. We propose a novel technique for bonding a lithium tantalate (LiTaO3) wafer to a silicon (Si) wafer at room temperature. The surface of the Si wafer is etched and activated by Ar plasma, while a thin film of Si is deposited on the surface of the LiTaO3 wafer under a high vacuum. The two wafers are then immediately brought into contact. A crack-opening method and tensile testing confirmed that the bond between the wafers was stronger than that produced by a surface-activated bonding method. An amorphous intermediate layer, approximately 8 nm thick, was observed at the bonding interface by transmission electron microscopy. Our proposed technique is useful for room temperature direct bonding of dissimilar materials with a large mismatch in their thermal expansivities.