User's Manual

Table Of Contents
eUniStone
PBA 31309
Assembly Guidelines
User’s Manual Intel Public 43
Hardware Description Revision 1.0, 1-Feb-2013
9.6.2.2 Alternative 2: Printing Solder
To print solder on the module a fixture must be used. The purpose of the fixture is to
get a flat surface and fix the stencil and module for printing. An example of how this
fixture can be designed is shown in Figure 19.
Figure 19. Solder Printing
1. Assemble the fixture to the bottom
2. Place the module in the cavity with the LGA pads upwards
3. Place the solder paste stencil on the fixture and make sure it fits to the tooling pins
and the module
4. Apply vacuum to fix the solder paste stencil
5. Apply solder paste on the stencil and print by using a blade
6. Turn everything (bottom, fixture and stencil) upside down.
7. Separate carefully the bottom from the fixture
8. Pick the module by a nozzle and place in the right position on the board
9. Reflow the solder.
9.7 Inspection
Automatic inspection of the solder paste printing before assembly is highly
recommended to ensure high yield and good long term reliability.
Solder_Printing.vsd
Vacuum hol es
Solder paste stencil
Cavity of the module
Tooling pins
Bottom
Fixture