GOALI: ELECTROMIGRATION STUDIES OF ELECTROLESS CU ON SUB-QUARTER-MICRON TEST STRUCTURES

微电子工业目前正在经历一场技术和材料的革命，用于连接集成电路中的单个设备（互连）。基于铜的金属化很可能取代铝金属化，铝金属化在硅微电子工业中占主导地位已有几十年了。在高电流密度（电迁移）的影响下，铜具有较低的电阻率和较高的扩散输运阻力。在这一点上，许多与铜金属化相关的问题已经得到解决。然而，随着电路越来越小的趋势，微电子工业可能会发现自己面临着目前困扰铝基金属化使用的相同限制因素：电迁移。本研究的目的是确定在集成电路中防止铜基金属化电迁移的重要参数。该目标将通过生成由多级铜互连组成的测试样品矩阵来实现，使用电化学过程沉积铜。铜的沉积参数对铜的微观结构特征有很大的影响，因此在实验中铜的沉积参数是一个变量。样品将被封装在陶瓷双管直列封装中，以模拟实际集成电路的工作环境。电迁移测试将在高温下进行，直到样品失效。聚焦离子束显微镜、扫描电镜、二次离子质谱和掠射x射线衍射等技术将用于表征和确定电迁移故障的来源。* * *

9709447 Vanasupa The microelectronics industry is currently undergoing a revolution in the technology and material employed to connect individual devices in an integrated circuit (interconnects). It appears that metallizations based on copper will likely replace the aluminum metallizations whose use has dominated the silicon microelectronics industry for decades. Copper offers a lower resistivity as well as a higher resistance to diffusional transport under the influence of high current densities (electromigration). At this point, many of the issues associated with converting to copper metallization have been addressed. With the trend for eversmaller circuits, however, the microelectronics industry is likely to find themselves faced with the same limiting factor currently plaguing the use of aluminum-based metallization: electromigration. The objective of this research is to identify the parameters that are important to preventing electromigration of copper-based metallization in integrated circuits. The objectives will be accomplished by generating a matrix of test samples composed of multiple levels of copper interconnects using an electrochemical process to deposit the copper. The copper deposition parameters will serve as a variable in the experiments since they strongly influence microstructural features of the copper. Samples will be packaged in ceramic daul in-line packages to simulate the operating environment of actual integrated circuits. Electromigration tests will be performed at elevated temperatures until the samples fail. Technics such as focused ion beam microscopy, scanning electron microscopy, secondary ion mass spectrometry and grazing incidence x-ray diffraction will be used to characterize and identify the source of the electromigration failures. ***