Packaged modules can be manufactured by providing or forming a substrate panel having first and second sides, and an array of units, and mounting one or more devices on the first side of the substrate panel for each unit. A first mold layer can be formed over the first side of the substrate panel to provide an assembly, with the first mold layer having an initial thickness that is greater than a final thickness, such that the initial thickness is sufficiently large to prevent warpage of the assembly where a similar assembly having a first mold layer with the final thickness would warp. One or more process operations can be performed on the second side of the substrate panel of the assembly, and a thinning operation can reduce the thickness of the first mold layer from the initial thickness to the final thickness.