Passitivation Location Location of areas without passitivation darker

UCSB Old TOB Signal Bond Damage Looked for damage on the signal bonds We found on all signal bonds the area near the very end of the wire was pocked It is at the same location of the discoloration of the passitivation seen on channels Approx. 70-210 mm from the wire bond feet

Old TEC Ring 5 Modules Built at UCSB Good News Bonds Higher ~150 mm Bias, ~350 Signal Less Damage Seen Bad News Discoloration seen of passitivation of DC pads, bias ring, and guard ring on bias and signal bonds DC Pads Guard Ring DC Pads Bias Ring Bias Ring

Old TEC Ring 7 Modules Built at UCSB Good News Bonds Higher ~150 mm Bias, ~350 Signal Less Damage Seen Bad News Discoloration seen of passitivation of DC pads, bias ring, and guard ring on bias and signal bonds Metal line deposited under bias bonds between bias and guard rings DC Pads Guard Ring DC Pads Bias Ring Bias Ring

UCSB Modules with New Bond Heights Bonding clearance over inside n+ metal edge increased for all module types R5- ~350 mm bias bonds and ~520 mm signal bonds R7- ~425 mm bias bonds and ~525 mm signal bonds TOB- ~450 mm bias bonds and ~550 mm signal bonds No visible damage seen under bias and channel bonds Plan on running modules for extended periods under voltage in the Vienna box