Method and structure for identifying lead-free solder
AssigneeIntel Corporation
InventorsTom E. Pearson, George Arrigotti, Christopher D. Combs, Raiyomand F. Aspandiar
Life of this patent
Estimating the term…
Abstract
A method and apparatus are provided for determining whether solder used during assembly of a printed circuit board is lead-free or not. This may include providing a pad on the printed circuit board and placing solder on the pad in a predetermined pattern. The solder may be heated so as to create reflow. The solder may later be examined to determine if the solder is lead-free.
Claims29
A method comprising:
- placing a predetermined solder pattern in a shape of a symbol onto a pad provided on a substrate;
- heating said predetermined solder pattern and turning the solder pattern to a liquid state;
- and
- cooling the predetermined solder pattern, turning the heated and cooled predetermined solder pattern to a solid state;
- wherein a visual appearance of said heated and cooled predetermined solder pattern is indicative of whether a solder paste used to form the predetermined solder pattern is lead-free by maintaining a substantially same pattern as the symbol of said predetermined solder pattern after heating and cooling the predetermined solder pattern when the solder paste used to form the predetermined solder pattern is lead-free.
A method comprising:
- providing a pad on a substrate;
- placing solder on said pad;
- and
- heating said solder so as to create reflow;
- and
- cooling said solder after the reflow is completed;
- wherein a visual appearance of said heated and cooled solder is indicative of whether said solder is lead-free based on the amount of reflow of said solder on said pad.
A method of identifying whether a printed circuit board is lead-free, said method comprising:
- receiving said printed circuit board having a heated solder pattern formed thereon;
- and
- identifying whether solder on said printed circuit board is lead-free based on whether said heated and cooled solder pattern is substantially similar to a predetermined solder pattern.
A method of identifying whether a printed circuit board is lead-free, said method comprising:
- receiving said printed circuit board having a heated and then cooled solder pattern formed on a pad thereon;
- and
- identifying whether solder on said printed circuit board is lead-free based on a distance that said solder pattern reflows by comparing the distance that said solder pattern reflows with at least one visual indicator provided at a certain location along the pad on said printed circuit board.
A method comprising:
- placing a solder paste in a predetermined solder pattern onto a pad on a substrate having a first visual indicator along side the pad including the words “LEAD-FREE BOARD” and a second visual indicator along side the pad including the words “LEAD BOARD” and a third visual indicator along side the pad and between the first visual indicator and the second visual indicator;
- heating and cooling said predetermined solder pattern;
- and
- determining that said solder is lead-free if said predetermined solder pattern after heating and cooling reflows a distance along the pad that does not extend to an area adjacent to the second visual indicator.
Dependencies are inferred from the claim text.