Performance of vertical power devices with contact-level copper metallization

Vertical power devices have been used to characterize device performance with contact level copper interconnects. R-dson (device resistance in the ''on'' state) measurements were obtained using three different probe configurations for various aluminum and copper metallizations. These measurements were used to make qualitative comparisons between aluminum and copper in terms of metal-to-silicon contact resistance and bondpad spreading resistance. Results indicate that contact resistance can be achieved with TiW/copper-based interconnects which is comparable to that of the standard Al to-Si contact. Results also suggest a significant decrease in bondpad spreading resistance with 2 mu m copper. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.