:: Talk About Yield

Survey Says

Si2 survey challenges DFM assumptions

The results of Si2’s January 2005 survey challenged three widely accepted assumptions about the IC cost spiral, yield management and DFM.

• Myth #1: Photomask pricing is critical. Survey respondents expressed concern about mask costs, of course, but also noted that photomasks are integral to the process. Respondents believe the real issue is design – specifically creating designs that assure acceptable yields. Photomask costs are a small fraction of design costs, they noted, and reducing design spins and cycle times was given a much higher priority. (Photomask cost tied with IC Libraries as the survey’s third most significant issue.)

• Myth #2. Mask data volume is critical. With design respins so much a part of the yield equation, EDA processing time – not mask data volume – received a higher priority from survey respondents. (55% ranked EDA application processing time as having the most significant impact on increasing data size. In second place with 20% was "no significant impact." All other issues received a response lower han 10%.)

• Myth #3. The industry is crying out for standards that link design and manufacturing as soon a possible. There is considerable nuance in reading the survey responses. For example, the top response to the question of how the industry can best collaborate on DFM was “by developing open-industry standards". But the industry as a whole does not want standards now because the DFM marketplace is immature and competitive. Companies typically do not see themselves as having a clear lead in their niche and want to delay on standards until their positions have stabilized. A good deal of information relevant to standards making is being created in supply chains but there is no clear consensus on how additional information can be exploited.
  
  Other survey results included:

• The top four responses to the question of the most significant DFM issues today were:
  -- Design and data preparation time (19% of respondents)
  -- Manufacturing respins (18%)
  -- IC libraries (12.5%)
  -- Mask costs (12.5%)

• The top four answers to how the best resolve today’s DFM issues were:
  -- Smarter EDA applications (15% of respondents)
  -- More complete characterization of manufacturing (15%)
  -- More characterization of impact of design on manufacturing (14.5%)
  -- Better integration of design, DFM and manufacturing software (14%)

• 75% claimed to understand their DFM issues and requirements "fully" or "quite well"

• 60% were less than satisfied that their DFM solution suppliers understand their issues.
  

To achieve fuller understanding of the survey responses and trends, Si2 also hosted a roundtable discussion attended by more than 25 companies, most of which were also DFM Survey participants.

Here's the abstract of the proceedings.

The topic of design for manufacturability (DFM) is turning up everywhere these days. Over the last several years, the semiconductor industry has come to recognize that its economic future may very well depend on parting with old ways and integrating the two previously separate worlds of design and manufacturing.

Recent survey data indicates that the vast majority of customers and suppliers fully expect their DFM methodology to change within the next 12 months. However, while awareness of the conceptual need to “tear down the wall” may have come into focus, industry clarity on getting to the solution has not. Even the definition of DFM brings an array of interpretations, depending on which segment within the supply chain is being asked.

For the complete account of the roundtable proceedings, click the link below.

Supply Chain Experts Add Insight into DFM at Industry Roundtable