PARAMETRIC
ADVANCED

DFY/DFM Solutions

Higher precision in LSI fabrication is increasingly vital as fabrication processes become further iniaturized.
NEC Electronics provides customer-pleasing quality in LSIs by taking such high-precision fabrication into consideration in its chip designs. Specifically, DFY (Design For Yield) and/or DFM (Design For Manufacturing) techniques such as OPC (Optical Proximity effect Correction) of mask or multi-cut vias have been introduced for this purpose.

Double cut via technology

As LSIs become ever more highly integrated, the number of vias per chip increases and the quality of these vias comes to affect the LSI's overall quality. NEC Electronics has introduced double cut via technology as a means of preventing problems while raising fabrication quality.
In particular, double cut vias are used only for interconnects between wires that do not affect the chip size or layout turnaround time. This improves the yield while preventing faults.

OPC (Optical Proximity effect Correction) processing

To improve the quality of increasingly miniaturized fabrication processes, NEC Electronics has introduced OPC processing technology for mask pattern generation.
Specifically, this processing considers the results of wafer fabrication before generating the mask pattern.

Smoothing of metal density

Metal density is another topic of increasing concern as fabrication processes become further miniaturized. NEC Electronics smoothes (evens out) the metal density at the layout stage in order to improve fabrication quality.

Redundant SRAM technology

Higher integration of LSIs has meant larger SRAM capacities, which makes the quality of SRAM manufacturing a topic of growing concern.
NEC Electronics provides redundant SRAM (SRAM with redundant bits), which enable electric weld fuses to be used to correct defect points.