超大规模集成电路互连系统的布线构造对散热的影响

应用一个三层互连布线结构研究了诸多因素尤其是布线的几何构造对互连系统散热问题的影响,并对多种不同金属与介质相结合的互连布线的散热情况进行了详细模拟.研究表明互连线上焦耳热的主要散热途径为金属层内的金属线和介质层中热阻相对小的路径.因此互连系统的几何布线对系统散热具有重要影响.在相同条件下,铝布线系统的温升约为铜布线的ρAl/ρCu倍.此外,模拟了0.13μm工艺互连结构中连接功能块区域的信号线上的温升情况,探讨了几种用于改善热问题的散热金属条对互连布线的导热和附加电容的影响.

Influence of Interconnection Configuration on Thermal Dissipation of ULSI Interconnect Systems

The effects of adjacent metal layers and space between metal lines on the temperature rise of multilevel ULSI interconnect lines are investigated by modeling a three-layer interconnect. The heat dissipation of various metallization technologies concerning the metal and low-k dielectric employment is simulated in detail. The Joule heat generated in the interconnect is transferred mainly through the metal lines in each metal layer and through the path with the smallest thermal resistance in each Ield layer. The temperature rises of Al metallization are approximately ρAl/ρCu times higher than those of Cu metallization under the same conditions. In addition, a thermal problem in 0.13μm globe interconnects is studied for the worst case,in which there are no metal lines in the lower interconnect layers. Several types of dummy metal heat sinks are investigated and compared with regard to thermal efficiency, influence on parasitic capacitance, and optimal application by combined thermal and electrical simulation.