It can perform fluxless reflow by formic acid reduction or hydrogen reduction.
Also, because of the vacuum process, voidless processing is possible.
Furthermore, reduction bonding equipment can perform low-temperature bonding of metals such as Cu and Ag by weighting after reduction.
Solder Bump SEM
By processing under vacuum condition, it is possible to press down the occurrence of voids, and to produce highly reliable equipment. Reflow of Pb-free solder bumps and narrow pitch bumps, which is difficult to remove oxide layer, is also possible. 
Formic acid reduction
Reoxidation time after formic acid reduction
After reduction of the solder ball with formic acid, confirm the wet condition of solder at each passing time of exposure to the atmosphere, and…,
Good wet condition even after 96 hours!!
Similar results were obtained for Sn3Ag0.5Cu.
Hydrogen reduction
Hydrogen gas can also reduce strong oxide layer!!
It is an equipment that bonds by applying temperature and we…
