Coplanarity improvement of high-rate CU pillar processes using high agitation to enable use of high acid, low CU chemistries

A method of electroplating by an electroplating system, the system comprising a spray jet array, and a copper (Cu) bath, wherein the Cu bath is characterized by a predetermined threshold of Cu concentration, and a predetermined threshold of acid concentration, the method comprising:

• spraying a fluid onto a substrate with the jet array, wherein the fluid has a same composition as the Cu bath and wherein spraying the substrate increases a deposition rate of a deposited Cu onto the substrate, wherein the jet array comprises a plurality of apertures disposed on a plate, wherein the plate is a first plate and the plurality of apertures is a first plurality of apertures, and wherein the jet array further comprises a second plate coupled with the first plate on a bottom side of the first plate, and a second plurality of apertures, wherein an outlet end of each of the first plurality of apertures and each of the second plurality of apertures extends through a top surface of the first plate, an inlet end of each of the first plurality of apertures extends through a bottom surface of the first plate, and an inlet end of each of the second plurality of apertures extends through a bottom surface of the second plate;
• depositing Cu onto the substrate while the jet array is spraying the Cu bath, wherein the predetermined threshold of acid concentration increases a bath conductivity of the Cu bath, and wherein the increased bath conductivity improves a coplanarity of copper structures being deposited on the substrate;
• spraying the substrate with jets formed through only the first plurality of apertures;
• ceasing to spray the substrate with jets formed through the first plurality of apertures;
• and
• spraying the substrate with jets formed through only the second plurality of apertures.