Non-vacuum processing – Openair-Plasma® unleashes new potential for the manufacture of semiconductors
Silicon wafers, chips, and high-performance semiconductors are highly sensitive electronic components. As these technologies have developed, so has low-pressure plasma technology as a manufacturing process.
The enhancement of the Openair-Plasma® process under atmospheric pressure opens up entirely new possibilities, in particular for automation. A vacuum is no longer required for plasma treatment, so process flows can be greatly simplified.
Nano-Plasma Cleaning of Silicon Wafers
Wafer manufacturing begins with a block of semiconductor material. This is sliced (sawed) into wafers, which are then polished in a chemical/mechanical process until the required surface roughness of a few nanometers is achieved.
In the next step, Openair-Plasma® is used as a highly efficient and simple procedure for super-fine cleaning of these nano-structures. One hundred percent of carbohydrates and particles are removed and error rates can be significantly reduced using this Openair-Plasma® cleaning.
Secure Joining–Reliable Wire Bonding with Plasma Cleaning of Contact Surfaces
After chips are created (diced out of the wafer) and separated, they are packaged by attaching them to lead frames and then providing them with housings. Secure joining, wire bonding, of the chip to the leads of the lead frame is critical for the reliable functioning of the integrated circuit. Wire bonding is generally performed in an ultrasound procedure, and for that step in the process, the contact surfaces must be perfectly clean.
Dry super-fine cleaning with Openair-Plasma® reliably removes all contaminants and carbohydrate residues. The result is secure bonding and a significant reduction in error rates.
Gluing Chips to Circuit Boards
Components are soldered to circuit boards in a cost-effective procedure called a wave soldering process. Up-to-date processes to accomplish this are typically lead-free. Wave soldering involves a higher temperature soldering bath, however, which in turn places greater demands on the adhesion of those components to the printed circuit board.
Surface activation of the components’ surfaces and the chips using Openair-Plasma® has shown a significant improvement in the performance of the adhesive used to fix the components in place for further processing in the solder bath.
ADVANTAGES &
PROPERTIES
of Openair-Plasma® systems
- Super-fine cleaning (component cleaning) without damaging sensitive structures;
- Targeted functionalization of surfaces for selective additional processing;
- Lean process layout, noticeable cost savings; and
- Lower error rates in bonding processes.
