Flip-Chip Bonding Using Superconducting Solder Bump
Flip-Chip Bonding Using Superconducting Solder Bump
复制标题
使用超导焊料凸块进行倒装芯片接合
DOI：
10.1143/jjap.34.4043
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发表时间：
1995
影响因子：
1.5
通讯作者：
S. Takada
中科院分区：
文献类型：
--
作者：
T. Ogashiwa;H. Nakagawa;H. Akimoto;H. Shigyo;S. Takada
利用超导焊点的倒装芯片键合包括两种技术：无酸热超声压缩球键合和在373 K下热超声压缩在衬底上的芯片面朝下键合。将具有68个凸点的超导测试芯片粘接在陶瓷衬底上。Nb/Pd薄膜的最大抗剪切强度为26.5 MPa，是Nb/Au薄膜衬垫的3倍左右。在4.2 K和273 K之间的20次热循环中，倒装芯片模块在原型设计或材料组合中均未发生灾难性故障。热循环前后在4.2 K下的电气检查试验表明，该超导焊点可用于超导IC芯片的连接。
Flip-chip bonding using superconducting solder bumps consists of two technologies: acid-free thermosonic compression ball bonding and face-down bonding of the chip on the substrate by means of thermosonic compression at 373 K. A superconducting test chip with 68 bumps formed on Nb/Pd film pads was bonded on a ceramic substrate. The maximum shear strength of a single solder bump for the Nb/Pd films was found to be 26.5 MPa, which was about 3 times higher than that obtained for Nb/Au film pads. The flip-chip module did not undergo catastrophic failures in either prototype design or material combination during 20 thermal cyclings between 4.2 K and 273 K. Electrical check tests at 4.2 K before and after the thermal cyclings suggest that the present superconducting solder bump can be put into practical use for superconducting IC chip connection.