FEB. 12 San Jose, California–Numerical Technologies today announced that it has entered into a joint development program with UMC, one of the world’s largest semiconductor foundries, to qualify and deploy Numerical’s Virtual Stepper system in a high-volume production environment.
Virtual Stepper is designed to facilitate the inspection of photomasks that use phase-shifting and optical proximity correction (OPC) technologies for subwavelength IC manufacturing. It is a comprehensive software system designed to analyze mask defect printability to determine whether defects on the mask will transfer into yield-killing defects on the wafer. UMC plans to use Virtual Stepper as a production standard to streamline outgoing and incoming photomask quality assurance.
Under the terms of the agreement, Numerical will work closely with the UMC photomask shop and wafer fab to qualify Virtual Stepper’s capabilities for advanced photomasks that contain both OPC and phase-shifting structures. The companies will also validate and deploy i-Virtual Stepper to use Internet-based communication to enable real-time inspection and communication between the photomask shop and the wafer fab group.
“Virtual Stepper is a system that has been designed to work effectively in both the fab or foundry environments and the mask manufacturing arena. It is essential for subwavelength mask manufacturing and acceptance,” says Atul Sharan, senior vice president, marketing, and business development, for Numerical Technologies. “As one of the world’s largest foundries, UMC uses the latest technologies to manufacture today’s advanced ICs. We believe this agreement with UMC will play a critical role in speeding the adoption of subwavelength technologies, which are needed to manufacture ICs at the 0.18-micron node and below. Virtual Stepper allows device and mask manufacturers alike to address a critical subwavelength challenge that can directly affect yield and performance.”
“As a foundry, we have multiple customers that depend on us to produce their most advanced devices–those with 0.18-micron and smaller design rules–that require subwavelength manufacturing technology,” says Peter Huang, UMC’s director of photolithography. “Because we recently deployed our 0.13-micron process, it is more critical than ever before for us to be able to cost-effectively ensure the quality of our masks, which ultimately results in
higher performance ICs and increased yield. Implementing Virtual Stepper will help reduce the overall cycle time, the number of unnecessary photomask repairs, and the number of falsely rejected photomasks. Technology agreements, such as this one with Numerical Technologies, ensure our ability to continue to manufacture leading-edge ICs for our customers worldwide.”
Subwavelength technologies enable the production of devices whose design features are smaller than the wavelength of light used to print the circuit designs on the wafer. These advanced technologies are critical for the production of the smaller, more powerful and energy-efficient devices demanded for today’s portable communications and computing applications. At the same time, they create new inspection challenges for both the mask manufacturer and the fab or foundry. It can be extremely difficult, for instance, to distinguish certain OPC features from device-killing defects. By automating the process of inspecting potential photomask defects, Virtual Stepper allows a move from an “inspect all, repair all” methodology to a more cost-effective and accurate “inspect all, repair what prints” approach.