A targeted-annealing system can automatically cure a conductive paste that may bind cascaded strips of a string. The targeted-annealing system can include a first heat-treating bar that may be heated to a first curing temperature, and can include a second heat-treating bar that may be heated to a second curing temperature. During operation, a controller of the targeted-annealing system can activate one or more actuators to conform the first heat-treating bar to a top surface of two cascaded strips, and conform the second heat-treating bar to a bottom surface of two cascaded strips. The first and second heat-treating bars may be aligned along an overlap portion between the two cascaded strips, and can heat the overlap portion to 160 degrees Celsius.