AP&S insights, news,
highlights and stories

Advanced under-bump metallization (UBM) with the AP&S e-less bench Vulcanio - 7 unbeatable facts that convince

Vulcanio - a fully automated eless UBM metallization tool for wafers up to 300 mm is our answer to the increasing importance of flip-chip bonding and further miniaturization of devices.

More and more devices are migrating from wire bonding to flip-chip to overcome the technical limitations of bonding technologies such as electrical resistance or geometric dimensions. Underbump metallization (UBM) is used as an alternative for the various device metallization options such as Al, Al alloys and Cu to act as an electrical contact, bonding layer and protective layer between the chip metallization and the subsequent solder bump technology. In this context, UBM deposition including pre- and post-wafer treatment is crucial for interface stability and reliability performance of the entire device.

For semiconductor manufacturing, the implementation of advanced, reliable UBM process technologies, highest throughput achievement and best TCoO performance of the production equipment are key success factors in this context.

The AP&S Vulcanio covers all these factors perfectly. Indeed, the batch tool was specially developed for under-bump metallization with electroless deposition technology on Al- and Cu-based substrates for metallization with nickel, palladium and gold. It has already been successfully used for mass production by leading semiconductor manufacturers since 2009. Since then, the system has been continuously developed and optimized in close cooperation with AP&S customers. These are the 7 Vulcanio facts that convince:

1. The fully automated high-throughput wet bench processes 50 wafers per batch.

2. Different wafer thicknesses, including thin wafers and TAIKO, can be processed with Vulcanio without any equipment modification.

3. Unique software and hardware features ensure exceptional deposition uniformity, highest process stability as well as bath longevity: Ni-bath with a bath life of 1-1.5 weeks, Pd-bath with 5 to 7 weeks and Au-bath with a bath lifetime of up to several months.

4. Thanks to a superior control system, reduction of Au metal thicknesses from > 0.5 µm to 0.05 µm is possible without sacrificing performance. Thinner Au metal layers in turn bring advantageous cost savings and lower risk of Au embrittlement in solder joints.

5. The high automation of the wet process tool ensures very high precision of the process steps with a superior operating cost ratio.

6. The equipment concept including individual tank and material design optimally support the process capabilities. Various Vulcanio machine layouts are available according to customer requirements.

7. The excellent reliability performance on wafers, from - 40 degr. C to + 125 degr. C., has been scientifically proven. 

The long use in the market, the continuous analysis and optimization in close cooperation with our customers, the scientifically proven good performance and the very positive customer feedback, characterize the AP&S e-less Vulcanio. For more information and technical data please contact our sales team: sales@ap-s.de