SDBG (Stealth Dicing Before Grinding) Process

Solutions

Smartphones and tablets are continually becoming thinner and supporting a higher processing capacity, which means that flash memory and memory controller chips must also become thinner. Current processes are focused on reducing chipping and improving thin wafer handling.
The SDBG process not only addresses these issues but also makes the following possible:

increase in the number of die per wafer
improvement in the die strength of thin die

What is the SDBG Process?

SDBG is the process of performing backside grinding after Stealth Dicing™ process. It produces narrow streets on thin die and improves die strength.
Using a die separator (DDS Series) after SDBG, it is possible to precisely separate the DAF (die attach film) which is used as a bonding material when laminating thin die.

Process Flow

Increased Number of Die per Wafer

Kerfs generated during Stealth Dicing™ process are extremely narrow. Thus, Stealth Dicing™ process contributes to producing narrower streets. It is expected to increase the number of die yielded from each wafer compared to the conventional dicing process.

Die Strength Improvement

In conventional blade dicing, front and backside chipping and processing marks remaining on the side wall can affect die strength.
In the SDBG process, die separation is performed at the modified section using Stealth Dicing™ process as its starting point, and the modified section is removed during backside grinding. Thus, it is possible to reduce front and backside chipping and produce thin die with a high die strength.

High Quality Separation of DAF (Die Attach Film)

By expanding DAF using the die separator (DDS Series) in a low temperature environment, it is possible to achieve high quality separation.
Dicing tape sag after expansion is eliminated using heat shrink, making it possible to transfer the die to the next die bonding process without re-laminating the dicing tape.