Design for manufacturability (DFM) is a hot topic for designers contemplating a move to advanced silicon processes. Fortunately, the foundries are a step ahead of them.
TSMC has rolled out two comprehensive DFM toolkits that are based on its Nexsys process technology. Based on a large amount of accumulated process data, the kits drive that process data back into EDA tools from key suppliers. They also include a number of TSMC services that increase yields and improve device performance.
From TSMC's standpoint, DFM means transmitting to the upstream physical-design tools information on process variances and pattern sensitivies. These include pattern density effects, stress effects, optical effects, and proximity effects. Some of these affect yields, while others affect performance.
The Yield Plus DFM toolkit includes action-required rules (Spice is required for these), recommended advisories, and guidelines for semiconductor design, as well as DFM utilities for implementation of rules and advisories. Design rules are provided as a minimum guideline, while DFM recommendations are given as a target for extension without increases in layout area.
The Yield Pro DFM toolkit includes a number of manufacturing services meant to quickly move a device into volume production. These include a lithography process-check (LPC) service, a yield sensitivity-analysis (YSA) service, a package modeling service, and scan diagnostics services.
TSMC's DFM toolkits are particularly crucial to the foundry's 65-nm Nexsys system-on-a-chip process, expected to see first wafer production in the fourth quarter.