EV Group unveils industry's first wafer bonding system for 450-mm SoI semiconductor wafers

SEMICON WEST 2011, SAN FRANCISCO, USA: EV Group (EVG), a leading supplier of wafer bonding and lithography equipment for the MEMS, nanotechnology and semiconductor markets, unveiled the semiconductor industry's first bonding system for 450-mm-diameter wafers manufactured from silicon-on-insulator (SOI) substrates.

Building on EVG's leadership in SOI wafer bonding, the new system – dubbed the EVG850SOI/450 mm – was created to support and facilitate the industry transition to 450-mm wafers from the current 300-mm standard. Leading SOI wafer provider Soitec will install, test and qualify the first EVG850SOI/450-mm system at its Grenoble, France, headquarters. Delivery is slated for fall 2011.

For more than 40 years, Moore's Law has been the primary driver for innovation in the semiconductor industry. The benefits of reduced cost per transistor, better performance and increased functionality enable increased transistor budgets for innovative designs. Because IC cost per square centimeter (cost/cm2) approximately doubles each decade, however, the industry has undergone a coincident transition in wafer size every eight to 10 years – while continuing to scale feature sizes – in order to stay on the path of Moore's Law.

SOI is expected to play an enabling role in the shift to 450 mm, as it not only answers most of the scaling challenges, but it also delivers better power/performance for sub-22-nm CMOS and 3D technologies compared to similar-geometry bulk CMOS. Wafer bonding is a crucial technique for fabricating SOI wafers, as it enables achievement of high-quality, single-crystal silicon films on one insulating layer to form SOI substrates.

The new EVG850SOI/450-mm wafer bonding system leverages EVG's strengths in wafer bonding technology to create a fully automated tool for production-level fabrication of SOI wafers. Moreover, because chipmakers will need an interim solution to optimize productivity for existing 300-mm capacity as the migration to 450 mm proceeds over the next few years, the system can serve as a bridge tool, allowing processing of both wafer sizes.

"Every bonded 300-mm SOI wafer and nearly 100 percent of all SOI wafers are fabricated on EVG systems. We delivered our first SOI bonding system in 1994, and our global installed base continues to grow with widened adoption of SOI substrates," noted EV Group executive Technology Director Paul Lindner. "One of the most important SOI fabrication processes based on wafer bonding is the Smart Cut layer transfer technology from Soitec, with whom EV Group has a longstanding collaborative relationship. Soitec is the ideal recipient of the first EVG 450-mm SOI wafer bonding system, and their evaluation of the alpha-tool will be invaluable for optimizing the system modules."

The EVG850SOI/450 mm consists of two process modules: a cleaning module for cleaning and pre-conditioning of wafers before wafer bonding, and an SOI pre-bonding module. In the pre-bonding module, the two silicon wafers are joined together either in a vacuum or in an atmospheric chamber. The tool is equipped with state-of-the-art 450-mm load ports and front opening unified pods (FOUPs). Most of the particle and metal ion contamination tests will be performed on 300-mm wafers due to the lack of 450-mm metrology systems.

The first tool in EVG's 450-mm arsenal, the new bonder will serve as the key starting point for the production of 450-mm SOI wafers, and can be utilized for the development of other EV Group 450-mm products, such as mask aligners and coating systems. An extension of the system with additional modules is planned as a further step to increase wafer throughput.

Paul Boudre, CEO, Soitec, said: "Soitec is willing to position in the 450-mm transition. With the launch of this new system, EV Group is offering the semiconductor industry a highly viable solution to ease the transition to 450-mm wafers. With our well established SOI material playing an increasingly greater role in fabricating next-generation ICs, we look forward to working with EVG to ensure this new system is ready to enter mainstream production in a timely fashion."