【摘要】 用基于铅铟合金线的引线键合(WB)工艺对单磁通量子(SFQ)多芯片的超导互连方法进行了研究,将铅含量75%,铟含量25%的铅铟合金线制备成WB线材,用超声楔形焊工艺成功实现SFQ芯片I/O接口焊盘的超导互连.拉力测试表明室温下铅铟合金线键合强度与同线径金线相当,优于同线径铝线;用开尔文四端法测量了铅铟合金线互连的多级超导转变温度以及线材与超导芯片之间的接触电阻,结果表明该铅铟合金线的超导转变温度为6.63 K,当温度降低至6.63 K或更低时,铅铟合金线的线阻以及线材与SFQ芯片I/O接口焊盘的接触电阻为0,实现了超导互连;并通过热冲击实验验证该WB结构具有优异的热稳定性.更多还原

【Abstract】 The wire bonding(WB) process based on lead-indium alloy wire was used to study the Single-Flux-Quantum(SFQ) multi-chip superconducting interconnection method. The lead-indium alloy wire with 75% lead and 25% indium was prepared into WB wire, the superconducting interconnection of the SFQ chip I/O interface pads was successfully realized by the ultrasonic wedge wire bonding process. The tensile test shows that the bonding strength of the lead-indium alloy wire at room temperature is equivalent to that of the gold wire of the same diameter, and is better than that of the same diameter aluminum wire; the multi-level superconducting transition temperature of the lead-indium alloy wire interconnection and the wire are measured by the Kelvin four-terminal method. The contact resistance between the lead-indium alloy wire and the superconducting chip shows that the superconducting transition temperature of the lead-indium alloy wire is 6.63 K. When the temperature drops to 6.63 K or lower, the wire resistance of the lead-indium alloy wire and the contact resistance of the wire and the SFQ chip I/O interface pad is 0, realizing superconducting interconnection. And the thermal shock experiment verified that the WB structure has excellent thermal stability.更多还原