The Production Process Of Solar Panels

Description of the specific manufacturing process of solar cells

(1) Slicing: Using multi-line cutting, the silicon rod is cut into square silicon wafers.

(2) Cleaning: Use conventional silicon wafer cleaning methods to clean, and then use acid (or alkali) solution to remove 30-50um of damage layer on the surface of the silicon wafer.

(3) Preparation of suede: anisotropic etching is performed on the silicon wafer with an alkaline solution to prepare a suede on the surface of the silicon wafer.

(4) Phosphorus diffusion: use a coating source (or a liquid source, or a solid phosphorus nitride flake source) for diffusion to make a PN+ junction, and the junction depth is generally 0.3-0.5um.

(5) Peripheral etching: The diffusion layer formed on the peripheral surface of the silicon wafer during diffusion will short-circuit the upper and lower electrodes of the battery, and the peripheral diffusion layer is removed by masking wet etching or plasma dry etching.

(6) Remove the backside PN+ junction. The backside PN+ junction is usually removed by wet etching or grinding.

(7) Making the upper and lower electrodes: using vacuum evaporation, electroless nickel plating or aluminum paste printing and sintering. The lower electrode is fabricated first, followed by the upper electrode. Aluminum paste printing is a process method that is widely used.

(8) Production of anti-reflection film: In order to reduce the reflection loss, a layer of anti-reflection film should be covered on the surface of the silicon wafer. The materials for making the anti-reflection film are MgF2, SiO2, Al2O3, SiO, Si3N4, TiO2, Ta2O5, etc. The process method can be vacuum coating method, ion coating method, sputtering method, printing method, PECVD method or spraying method.

(9) Sintering: Sinter the battery chip on the base plate of nickel or copper.

(10) Test classification: according to the specified parameter specifications, test classification.