Mi Equipment Korea said on Friday that it will be supplying its latest z-force laser assisted bonder (ZLAB) __ the Ai Series __ to a global chip assembly and testing company.
A die cut out from the wafer is placed on a board with the copper pillar bump facing it. Then, infrared reflow equipment is used to solder the die onto the board. Vendors can underfill empty spaces with heat-resistant material or conduct a molding process afterwards, then the package is tested before shipping.
Infrared reflow equipment is usually atop the production melt where the substrates take turns being soldered.
This is good for mass production. However, the chip and the entire printed circuit board where it is placed on are exposed to heat for five to seven minutes during this process.
This could cause them to warp and cause a non-wet effect __ where the die isn’t soldered properly.
Companies have been using laser assisted bonders (LAB), which shoot laser to the local area of the die for the soldering process that hastens the process to one to two seconds, to overcome this problem.
However, as chips gets thinner and smaller, even the use of LAB has been insufficient to solve the non-wet problem entirely.
High-end chips and boards are thinner than 100 micrometers, which means they warp even more when heated for too long. Chips with a lot of I/Os such as application processors, CPU and GPU are especially vulnerable to this.
Mi Equipment Korea’s ZLAB added a feature that presses the chip down finely from the top (hence “z-force”).
It can use a force between 3N to 100N to press down the chip __ it can support up to 500N.
This has resolved the non-wet problem, the company said, and has also overcome the misalignment between the chip and the printed circuit board that could occur. ZLAB also allows vendors to monitor the temperature.
The equipment is the first in the world to use z-force on a LAB. Mi Equipment Korea said it has filed for related patents in South Korea, China and the US. Patents has already been registered in Taiwan.
Mi Equipment Korea is a subsidiary of Mi Equipment, which is listed on Malaysia’s bourse.
A company spokesperson said the equipment is expected to be used widely in the packaging of next-generation logic chips.
Mi Equipment Korea was also aiming to finish the development of a laser compression bonder, a machine that picks up the chip for laser bonding, they added.