Steel screen mesh is SMT template, which is a special mould for SMT; its main function: help the solder paste deposition. The goal of this study is the accurate number of solder paste transferred to the exact location of PCB air.
The development of SMT Technology: SMT steel screen mesh (SMT template) was also applied to the adhesive agent process.
Evolution of steel screen mesh：
Initially, the steel screen mesh is made by screen, so that it is called the screen.At the start, we use nylon polyester mesh. In the later, due to the durability of the relationship, it is the emergence of barbed wire, copper wire and stainless steel wire mesh.But no matter what the material of the wire mesh,they all have the disadvantages of good forming and low precision.
With the development of SMT, the higher requirements of the steel screen mesh, the steel net is produced. Material costs and the production of the difficult process, the initial steel mesh is made of iron / copper, but also because of easy corrosion, stainless steel mesh to replace them, which is now the steel screen mesh.
Classification of steel screen mesh:According to the SMT stencil making process, it can be divided into: laser template, template electropolishing, electroforming stencil, ladder template, template, template electroless nickel plated etched template.
LaserStencil:Directly using the data file production, reduce the production error link;SMT template: full open position precision error is less than 4 m;The SMT template opening geometry, it is beneficial to the forming of solder paste printing.Laser steel mesh production requires the following information:1, PCB 2, data files.
PCB: the right, no deformation, damage and fracture;
Data file: Flextronics in Xinyu Iron and steel net (SMT) template processing group can accept a variety of CAD data format: Gerber, HPGL, *.JOB, *.PCB, *.GWK, *.CWK, *.PWK, *.DXF, *.PDF and the following software design of data: PAD2000, powerpcb, GCCAM4. 14, PROTEL, AUTOCADR14 (2000), CLIENT98, CAW350W, V2001.If the data is too large, we should compress the transmission, we can use *.ZIP, *.ARJ, *.LZH and other compression formats;It must also contain character layer data, in order to check the positive and negative data, component categories, etc..