Wafer Bumping Paste
Solder bumps on wafers may be produced by a variety of processes. For bumps with a pitch greater than 100microns, solder paste is often used to form the bump. Solder bumping of the top surface of BGA and PGA substrates for solder-on-pad (SOP) usually uses a very fine solder paste rather than plating. Formation of the much larger (0.3-0.6mm pitch) solder bumps on waferlevel CSPs is by a ball-drop process.
Solder Paste Blog Posts
For this week’s World of Solder Preforms series installment, Brandon Judd explains the importance of reflow profiling: Solder preforms are a very common method of reducing voiding in a soldered device with larger X/Y dimensions. Compared to solder paste (which is approximately 50% flux by…
It sounds bad for me to say this, but I have a lot of SMT magazines cross my desk and, honestly, the solder paste articles rarely draw my interest. I work in a world of solder preforms and that’s really where my mind is at, currently. A recent exception is a paper written by Eric Bastow (Assistant…
Folks, Richard asks: Dear Dr. Ron, Recently we had a solderability problem with tin-finished component leads and SAC305 solder paste. One of our engineers claimed that the problem was that the tin finish melts at too high a temperature (Tm= 232°C) for the SAC305 solder paste (Tm = 219°C)…
Andy C. Mackie, PhD, MSc
Senior Product Manager, Semiconductor Assembly Materials
From One Engineer to Another®
All of Indium Corporation’s products and solutions are designed to be commercially available
unless specifically stated otherwise.