space 140 to allow air to escape from planar space 140 flip chip assemblies 100 must be positioned in cleaning solution 220 such that only a portion of the perimeter of planar space 140 is submerged this positioning is accomplished in one embodiment by controlling the descent of flip chip assemblies 100 into cleaning solution 220 in the case that tank 210 is already filled with cleaning solution 220 alternately in the case that cleaning fixture 500 600 or 700 already resides within tank 210 the filling of tank 210 with cleaning solution 220 is controlled so that the surface of the bath of cleaning solution 220 rises slowly enough to allow planar space 140 to be completely filled with cleaning solution 220 prior to the entire perimeter of planar space 140 becoming submerged thus allowing all air in planar space 140 to escape prior to submergence in the embodiment of fig6 second cleaning fixture 600 employs an incline of 45 degrees from vertical in several embodiments this angle is thought to be a fair compromise between the needs of a higher angle for purposes of reducing the time to fill solvent tank 210 or increasing the speed with which the cleaning fixture may be lowered into cleaning solution.