Method of wave soldering thin laminate circuit boards

A method of preserving solder connections of components mounted on a circuit board during wave soldering, the method comprising the steps of:

• providing a printed circuit board having a thickness of not more than 0.08 mm, a first flip chip attached with solder bump connections to a first surface of the circuit board, a reflow-soldered component attached to the circuit board, and a leaded component disposed on the first surface and having leads extending through through-holes in the circuit board to an oppositely-disposed second surface of the circuit board;
• placing the circuit board on a pallet such that the second surface of the circuit board contacts the pallet, the pallet supporting the circuit board at a perimeter thereof and having a raised pedestal that contacts the second surface of the circuit board at a location opposite the flip chip and inwardly from the perimeter, the pallet having an access directly opposite the leaded component so that the leads of the leaded component are exposed, the pallet having a cavity in which the reflow-soldered component is received;
• applying a force to the circuit board at a location on the first surface opposite the pedestal so as to ensure contact between the pedestal and the second surface of the circuit board opposite the flip chip and to limit edge-to-edge deflection within the circuit board to not more than 0.25 mm;
• and
• placing the pallet on a wave soldering apparatus and then, after preheating the second surface of the circuit board to a temperature of up to 200° F. and without preheating the first surface of the circuit board, and while maintaining the force applied to the circuit board, wave soldering the second surface of the circuit board through the access in the pallet so that the leads of the leaded component are soldered to the circuit board and the solder connections of the flip chip do not fracture or separate.