When we say SMT stencils, it refers to the mold that used for PCB assembly or SMT. There are SMT stencils or glue-in stencils which are laser-cut solder paste stencils permanently mounted in a stencil frame using a mesh border to tightly stretch the stencil foil taut in the frame.

Classification of stencils

1.Non electro-polished Laser cut stencils.

This stencil is the most common used in PCB assembly industry. This kind of stencil can be in high precision and cost will be not expensive. If there’s non BGA or QFP package, this one can be used for most PCB boards.

2.Electro-polished laser cut stencils.

Electro-polished stencil, also know as electrochemical deburring stencil is used for fine pitch.

If there is BGA or QFP package, it is better to use this one instead of laser cut stencils. Using electropolishing elicits a significant improvement in printing, particularly for very small pad apertures, as solder paste is distributed better thanks to the smoothed walls.

3.Step SMT stencils

Step-up and step-down stencils have been used in PCB industry for more than a decade. This is really helpful for integrating mixed components with different paste requirements onto a single PCB. Linked Electronics can make a step-up and step-down stencils with many different thickness onto one stencil, that is 0.08mm 0.1mm 0.12mm 0.15mm 0.2mm 0.25mm 0.3mm.

4.Nano coating stencil

Electronics devices is getting much smaller and more dedicated and many new package are now appear, BGA COB, which has the pin space less than 0.4mm. This is really a big challenge for the PCB assembly.And the traditional technique cannot meet the requirement. Thanks to the nano coating stencils made by Linked Electronics

It increases paste transfer efficiency. NanoSlic Gold is applied using a proprietary application process, thermally cured and bonded to the stencil surface and aperture walls. For nano coating stencils, less clean job required and greatly reduce the quality issue for the PCB assembly work.