| Adhesive |
Materials used to hold components in place during wave or reflow soldering which may become a permanent part of the assembly, or
be subsequently removed. |
| Aperture |
An opening in the stencil that corresponds to a land area on the circuit to be printed. |
| Aspect Ratio |
A ratio of the thickness of the board to its preplated diameter. A via hole with aspect ratio greater than 3 may be susceptible to cracking. |
| Azeotrope |
A blend of two or more polar and nonpolar solvents that behaves as a single solvent to remove polar and nonpolar contaminants. It has one boiling point
like any other single component solvent, but it boils at a lower temperature than either of its constituents. The constituents of the azeotrope cannot be
separated by distillation. |
| Blade Attack Angle |
The angle formed between the stencil and the squeegee blade during squeegee travel. |
| Blowhole |
A void in a solder connection created by outgassing during the soldering process. |
| Bond Liftoff |
The failure condition reflected by the separation of a lead from its bonding pad. |
| Butt Joint |
A surface mount device lead that is sheared, so that the end of the lead contacts the board land pattern.(Also called I lead). Butt joint is made by
converting the leads of conventional DIP packages to suit surface mounting. |
