A type of open, known by a number of names (including crocodiling, surfboarding, Manhattan effect, drawbridging, Stonehenge effect, billboarding, etc.). This is a soldering defect in which a chip has been pulled into a vertical or near-vertical position with only one side soldered to the PCB. It is typically caused by force imbalances during the reflow soldering process.
Process and design-related causes of Tombstoning in PCB Soldering:
Reflow-related causes of Tombstoning in PCB Soldering: