Wafer fixing surface paste method, SMT printing steel mesh and wafer fixing device

The invention discloses a wafer fixing surface paste method to fix and attach a wafer on a substrate. The method comprises the steps that solder paste is printed in a primary solder paste printing area on the substrate to form a primary solder paste layer; the substrate is heated and cooled to volatilize a flux in the primary solder paste layer; solder paste is printed in a secondary solder paste printing area on the cooled primary solder paste layer to form a secondary solder paste layer, wherein the area of the secondary solder paste layer is smaller than the area of the primary solder paste layer; the wafer is attached on the substrate through the secondary solder paste layer; and reflow soldering is carried out on the substrate on which the wafer is attached to fix and attach the wafer on the substrate. Compared with the prior art, the method provided by the invention has the advantages that a part of the solder paste which is not attached is heated to volatilize the flux, which effectively reduces the si