Die attach, also known as die bonding, is the process of attaching (or bonding) a die (or chip) to a substrate, package or another die. This process can take on many forms and can be applied in many different ways. These differences are entirely dependent on the desired application of the user.
Palomar Technologies systems and services generally provide two levels of attachment:
In these two categories, there are several degrees of attachment - different specifications of materials present different challenges.
Eutectic Die Attach Methods
- AuSi eutectic scrub
- AuSn eutectic solder attach
- PbSn preform
- High-accuracy placement of optical components
- High-precision component attach using Ag epoxy
Epoxy Die Attach Methods
- Dot, line, pattern dispense
- Time pressure dispense
- Epoxy high-precision component attach
- Conductive and non-conductive epoxy use
- P-side down laser attach
Pick-and-place methods are also employed in die attach. This is the method of picking a die from a location and placing it in its desired location; doing so precisely using fiducial or other markings on the die, often in a + or x pattern. In certain cases with complex die attach, double pick-and-place is required. This furthers the accuracy of the placement, but on the downside decreases the throughput.