TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Method: Alternatively, metallization of solar cells comprises attaching a solar cell on a superstrate; forming contact holes through the superstrate; forming metal contacts of the solar cell while the solar cell is attached to the superstrate; and separating the solar cell from other solar cells that are also attached to the superstrate during formation of the metal contacts of the solar cell. Attaching the solar cells on the sheet of polymer film comprises bonding back sides of the solar cells on the sheet of polymer film so that front sides of the solar cells are facing up relative to the sheet of polymer film during metallization, the front sides being opposite the back sides and face the sun to collect solar radiation during normal operation. The method further comprises after forming the contact holes but prior to forming the metals in the contact holes, forming masks on the sheet of polymer film to protect portions of the sheet of polymer film during the electroplating of the metals. The metals are formed in the contact holes by sputtering. Each of the solar cells comprises a sliver of silicon wafer having a front side surface from along the thickness of the wafer, the front side surface being configured to face the sun to collect solar radiation during normal operation. The metal contacts comprise copper. The metal contacts electrically connect to P-type doped and N-type doped regions of the solar cells on the back sides of the solar cells. The polymer film comprises polyimide. The solar cell is attached to the superstrate using an adhesive. Forming the metal contacts of the solar cell comprises depositing metals in the contact holes; and electroplating the metals to form the metal contacts. The superstrate comprises polymer film. Preferred System: In system for metallization of solar cells, the sheet of polymer film supports the solar cells during electroplating of the solar cells to form the metal contacts; the sheet of polymer film supports the solar cells during etching of the solar cells to form contact holes in the solar cells; the sheet of polymer film supports the solar cells during formation of metals in the contact holes; or the sheet of polymer film supports the solar cells during formation of a mask over the back sides of the solar cells. Preferred Array: In the solar cell array, the string of solar cells comprises sliver cells or back contact solar cells.