In respondse to external demand, Tokyo-based machinery manufacturer Mitsubishi Heavy Industries Ltd (MHI) has launched wafer bonding services using its wafer bonding systems, which have been developed in-house and are capable of bonding different kinds of materials at room temperature.
Up to now the firm has offered trial services to businesses and other potential users considering adopting the system. Now, those services have been expanded to include businesses and research institutes with no immediate plans to acquire the system. In launching the new services, MHI aims to boost recognition of the effectiveness of room-temperature wafer bonding (a technology originating in Japan) in order to expand machine sales. The firm also aims to develop bonding services into a new areas of business.
Room-temperature bonding is a process where, by irradiating ion beams and atom beams in a vacuum, wafer surfaces become activated and bond. Because no heating is necessary (unlike conventional bonding), room-temperature bonding can be applied to bond materials with different coefficients of thermal expansion. Moreover, the technology is suited to the production of micro-electro-mechanical systems (MEMS) devices, which demand superior finishing precision, and biodevices that cannot be heated. Bondable materials include silicon, oxide dielectrics, glass, compound semiconductors, metals, and ceramics.
MHI completed development and began marketing its first room-temperature wafer bonding machines in 2005. The lineup currently includes a fully automated system accommodating wafers up to 12 inches (300mm) that is capable of manufacturing three-dimensional (3D) integrated LSI (large-scale integration) circuits. This newest system is rapidly entering use in fields including MEMS sensors, light-emitting diodes, high-frequency devices, biodevices, power devices, etc.
MHI says that, up to now, businesses and institutions planning to acquire its room-temperature wafer bonding machine have confirmed the system's bonding performance and quality via bonding tests performed at MHI using actual material samples. In recent years, as the room-temperature bonding process itself has become a focus of interest worldwide, MHI has seen a significant increase in such material bonding requests, especially from university and business research laboratories and factories engaging in small-lot production. MHI hence decided to accept requests for bonding services regardless of whether the user plans to acquire a machine or not.
The new bonding services are performed using four demonstration systems at the Technology & Innovation Headquarters' Advanced Technology Research Center in Yokohama and the Machine Tool Division in Ritto City (Shiga Prefecture). Fees vary, depending on factors such as wafer size, number of units to be bonded, etc. Trial bonding of smaller-size chips is also performed under designated conditions.
