Temperature Determination Methods on Copper Material for Highly Accelerated Electromigration Tests (e.g., SWEAT)

Published

February 1, 2003

Author(s)

Jochen von Hagen, Harry A. Schafft

Abstract

Highly accelerated electromigration tests conducted at wafer level require meaningful measurements of the stress temperature of the test line. Estimates of the test temperature can be made with the use of the temperature coefficient of resistance, TCR , before significant electromigration damage occurs and with the use of the thermal resistance of the test line as electromigration damage progresses to line failure. Each approach depends on an assumption of linearity: for the use of TCR it is the linear dependence of resistance on temperature, and for the use of thermal resistance it is the linear dependence of stress temperature on power dissipation. For testing aluminum test structures these assumptions are adequately well obeyed to approximately 300 degrees C. This is not the case for testing copper, the new metallization material. Stress temperatures as high as 600 degrees C are encountered in highly accelerated electromigration tests. At such high temperatures, the assumptions of linearity are no longer valid and large over-estimates of the stress temperature will result. We show how to correct TCR estimates of the stress temperature by the use of recommended values for the resisitivity of pure, bulk copper with temperature. We obtain a suitable value for the thermal resistance of the test structure from the slope of the temperature versus power dissipation curve at temperatures near the desired stress temperature. Uses of the approaches are demonstrated.

Proceedings Title

2002 IEEE International Integrated Reliability Workshop Final Report

Conference Dates

October 21-24, 2002

Conference Location

Lake Tahoe, CA, USA

Conference Title

2002 Integrated Reliability Workshop

Pub Type

Conferences

Keywords

copper, reliability, temperature coefficient of resistance, test structures, testing, thermal resistance, electromigration

Citation

von Hagen, J. and Schafft, H. (2003), Temperature Determination Methods on Copper Material for Highly Accelerated Electromigration Tests (e.g., SWEAT), 2002 IEEE International Integrated Reliability Workshop Final Report, Lake Tahoe, CA, USA (Accessed July 27, 2024)