Space, checkedClearance measured, not assumedCold plateopening for the fibreLidcavity for the wire loopDiebonded face downInterposerbump field on topFAU ÷ lid apertureBond loop ÷ cavityBump field ÷ dieMeasured volumes against keep-outs — two engines cross-checked, and a negative control that must fail if the check cannot fail.Cold platefibre openingLidwire-loop cavityDiebonded face downInterposerbump field on topFAU ÷ lid apertureBond loop ÷ cavityBump field ÷ dieMeasured volumes vs keep-outs — two engines cross-checked.A negative control must be able to fail.Fibre array vs lid and cold plate, wire loop vs cavity, bump field vs die — each a measured volume, with a control that must fail. SwipeSwipe the figure to read it — tap for the full viewEvery check ships with a negative control, so it is proven capable of failing.Lumicule