Use of pulsed-DC wafer bias for filling vias/trenches with metal in HDP physical vapor deposition

A method for filling one or more features on a substrate having a field area with a conductive material, comprising:

• (a) depositing a barrier layer on the substrate;
• (b) generating a glow discharge in an inert gas atmosphere at a pressure from about 0.1 to about 5 mTorr between a target and the barrier layer by applying a negative bias to the target:
• while
• (c) applying a pulsed DC bias having a DC positive voltage portion and a DC negative voltage portion to the substrate at a maximum negative voltage from about -20 V to about -200 V to preferentially deposit aluminum or copper within the one or more features.

An apparatus for filling one or more features on a substrate having a field area with a conductive material, comprising:

• (a) a processing chamber which generates a glow discharge in an inert gas atmosphere between a target and a patterned substrate to be processed by a negative bias generator capacitively coupled to the target;
• (b) a pulsed DC bias generator capacitively coupled to the substrate;
• and
• (c) a system controller programmed to control application of a pulsed DC bias having a DC positive voltage portion and a DC negative voltage portion to the substrate with the pulsed DC bias generator to preferentially deposit a conductive material into the one or more features on the patterned substrate.

An apparatus for filling one or more features on a substrate having a field area with a conductive material, comprising:

• (a) a processing chamber which generates a glow discharge in an inert gas atmosphere at a pressure from about 0.1 to about 5 mTorr between a target and a patterned substrate to be processed by applying a negative bias to the target;
• (b) a pulsed DC bias generator capacitively coupled to the substrate at a maximum negative voltage from about -20 V to about -200 V;
• and
• (c) a system controller programmed to deposit a barrier layer on a patterned dielectric layer on a substrate, and to apply a pulsed DC bias having a DC positive voltage portion and a DC negative voltage portion to the substrate with the pulsed DC bias generator to preferentially deposit a conductive material into the features on the patterned substrate.