Wednesday, July 26, 2006

Why can't we do it in EDA?

This was the questioned posed by Chairman of Orb Networks and former CEO of Cadence, Joe Costello in his DAC 2006 keynote speech.

The “it” referred to here is the mix and match of new plug-ins (internal and external), bundling things on top of others’ offerings and selling directly to customers.

With the increasing complexity of technological challenges compounded by rising market pressures, it does indeed benefit both the big EDA companies as well as the small start-ups with niche solutions to collaborate. However, opening the tools and making them pluggable is not without its major share of teething issues. While standards do take a long time to be formulated and then adopted, they’ll still be required to an extent for “universal plug-ins”.

One scenario is where EDA companies have the basic engines for the standard design activities. To these, smaller niche companies provide their plug-ins for value-addition and tackling of issues related to leading edge designs. With a uniform standard, these companies can go with their plug-ins to various EDA companies. In its absence however, each EDA company will need to work closely with these smaller companies and sell the complete “bundle with options” to the user.

A point to be noted here is that it’ll be naïve to assume that the present basic engines are implemented in a modular fashion where a plug-in can be used in a quasi seamless fashion. Then comes the question: if addressing of the leading edge issues is done in a modular fashion by the smaller companies who are free to sell their wares to the other big EDA companies, what is in it for the big EDA companies? What will be their competitive edge? But on the flip side, if the major EDA companies persist in attempting to do everything on their own, given the complexities and constraints, it’ll not result in much growth for the EDA industry.

Interestingly, there are signs of the industry moving in this direction. For DFM, with TSMC sharing their process information with the EDA companies to integrate into their design flow is one example. This can be treated as a “plug-in”.

Let’s take an example here: Synopsys recently came out with 3 tools in the DFM space - LCC (lithography compliance checking), CMP (chemical-mechanical polish) checking, and CAA (critical-area analysis). As per the press note, LCC inspects GDS-II files using a rapid-computation model of the lithography process, calibrated with foundry data. This scan predicts the actual shapes the mask features will produce, across the focus window of the lithography step. It then examines these features against a rule set to detect pinch-off, end-shortening, bridge, and other faults that could occur with a reasonable probability.

The normal output of the device is a color-coded die map: green for areas that pass, yellow for areas of concern, and red for trouble spots. Design teams that are knowingly pushing the litho rules can look under this graphic presentation at a numerical database that will give them actual predictions of critical dimensions.

Designers can then invoke an auto-correction tool, which is based on extensive, process-dependent heuristics, to deal automatically with the majority of the problems—adding space between lines, moving edges or corners, and other such reasonable measures.

Now reconsider the situation with a small EDA company working on the basic LCC part. It takes inputs from the lithography process model provided to it by the big EDA vendor (I don’t think the big foundries will be that comfortable in working closely with the smaller companies in handling their process data!). The GDSII is also provided as an input from the big EDA vendor’s tool(s). Finally the auto correction tool can be provided by either.

I cite this example because while these three new tools do attempt to handle the first order problems, they do not even begin to cover all the important sources of variation in 90-nm and finer geometries. TSMC cites more than 2000 independent sources of potential trouble.

I see a hybrid approach in the near future………

No comments: