Atomic layer deposition of copper seed layers

Deposition of thin and conformal copper films has been examined using atomic layer deposition as possible seed layers for subsequent electrodeposition. For this investigation, the copper films were deposited on glass plates as well as on Ta, TiN, and TaN films on silicon wafers. Typical resistivities of these films ranged from 4.25 mu Ohm cm for 20 nm thick copper films to 1.78 mu Ohm cm for 120 nm thick films. The adhesion of the copper films deposited on TiN and TaN at 300 degrees C was excellent. These films were highly conformal over high aspect ratio trenches. (C) 2000 The Electrochemical Society. S1099-0062(00)06-118-6. All rights reserved.