Whoever first coined the cliché “Don’t sweat the small stuff” didn’t work in nanotechnology.
It’s a phrase that helps us put things into perspective. But if you’re in the compound semiconductor industry and measure things in micrometers, the small stuff is the only stuff worth sweating.
There are two general obstacles that IC manufacturers struggle to solve:
1. Substrates undergo too much stress during production
Extreme heat and harsh chemicals can be detrimental to substrates of any thickness, let alone substrates that are exceptionally thin.
2. The current process is no longer efficient
Inefficiency can come in many shapes and sizes. Whether the materials are costing too much money or throughput is too low, they must be addressed.
In an effort to explore the limitations of temporary bonding and how to maneuver them, we experimented with some different carrier materials and found a promising way to bolster substrate tenacity while reducing process complexity and decreasing cost of ownership.
A Heart of Glass
When Blondie first sang those words in 1978, she was referring to the fragile nature of glass. As a temporary bonding carrier, however, we’ve found it’s quite the opposite. As substrates less than 100 µm thick become more and more common, glass is showing to be a wonderful carrier for both front-end and back-end processing for several reasons:
1. It’s relatively strong
When thinned to the appropriate thickness (both 0.7 mm thick and 1.1 mm thick were good), the glass proved to be a robust temporary bonding carrier, even when using the mechanical release debonding method. The glass carriers also showed to be relatively stable when we adjusted the coefficient of thermal expansion (CTE), and they lead to much less substrate bowing than a sapphire carrier.
2. It’s transparent
This might not seem like a big deal until you think of how time-intensive it can be to inspect for bond lines, bubbles, and other defects in a non-transparent carrier. Because glass is transparent, the defects are more easily and more quickly identified, saving the end user time and money.
3. It’s cost-effective
Of course, this isn’t leftover glass from the bottle manufacturer, but glass is a relatively cost-effective material to procure and handle. Compared to sapphire, glass gives users better results for less.
Check out our bonding and debonding material portfolio here
CS Mantech, Integrated Circuits, glass, Apogee, Compound Semiconductor Manufacturing, Datastream