Deposition of Low Stress and Low Resistivity Copper Conductive Layers by Electroplating Employing Copper-hexafluoro-silicate Electrolytic Solution

摘要

Copper conductive layer for VLSI interconnection is deposited by electroplating employing newly developed copper-hexafluoro-silicate electrolytic solution. Lower resistivity and stress copper layer with better adhesion can be deposited comparing with the layer by conventional copper-sulfate solution. Therefore, highly (111) oriented and low resistivity layer is obtained from this low stress layer. A resistivity of 1.8 μΩ-cm is obtained in this layer after annealing at 300°C. This resistivity is lower than of 2.0 ～ 2.2 μΩ-cm by copper-sulfate solution conventionally used.