摘要 |
An integrated copper deposition process, particularly useful for forming a copper seed layer in a narrow via prior to electrochemical plating of copper, including at least one cycle of sputter deposition of copper followed by sputter etching of the deposited copper, preferably performed in a same sputter chamber. The deposition is performed under conditions promoting high copper ionization fractions and strong wafer biasing to draw the copper ions into the via. The etching may be done with argon ions, preferably inductively excited by an RF coil around the chamber, or by copper ions, which may be formed with high target power and intense magnetron or by use of the RF coil. Two or more cycles of deposition/etch may be performed. A final flash deposition may be performed with high copper ionization and low wafer biasing.
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