Stress-induced voiding under vias connected to wide Cu metal leads
Stress-induced voiding under vias connected to wide Cu metal leads
复制标题
连接到宽铜金属引线的通孔下应力引起的空洞
DOI：
10.1109/relphy.2002.996654
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
William R. McKee
中科院分区：
文献类型：
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作者：
E. Ogawa;Joe W. McPherson;J. A. Rosal;K. J. Dickerson;Tz;L. Y. Tsung;M. K. Jain;Tom Bonifield;J. C. Ondrusek;William R. McKee
在铜基、深亚微米、双衬底技术中，当通孔连接到其下方的宽金属引线时，在通孔下形成了应力诱导的空洞。当Cu在完全约束之前没有适当退火时，由于晶粒生长而产生的空位过饱和导致了空化。空化的驱动力是应力迁移，空化速率在/spl sim/190/spl℃时达到最大值。提出了一个扩散模型，表明空化机制主要是与宽铜引线连接的过孔的问题。热机械应力指数为3.2，扩散活化能为0.74 eV。
Stress-induced voiding is observed in Cu-based, deep-submicron, dual-damascene technologies where voids are formed under the via when the via connects to a wide metal lead below it. The voiding results from the supersaturation of vacancies that develops due to grain growth when the Cu is not properly annealed prior to being fully constrained. The driving force for voiding is shown to be stress migration with a maximum in voiding rate observed at /spl sim/190/spl deg/C. A diffusional model is presented which shows that the voiding mechanism is an issue primarily for vias connected to wide Cu leads. A thermomechanical stress exponent of 3.2 and a diffusional activation energy of 0.74 eV were determined for this stress-induced voiding mechanism.