TSMC on 450mm transition: Lithography key!

TSMC unveiled its schedule for 450mm mass production at the recently held SEMICON Taiwan 2012 450mm Supply Chain Forum. Focusing on lithography as the key, Dr. C.S. Yoo, senior director of the 450mm program at TSMC, noted that IC makers and equipment suppliers should fully leverage the G450C. They need to work and innovate to make the 450mm transition a great success.

TSMC has always been in the relentless pursuit of technology innovation. It has been part of all of the computing waves that have driven the market growth. Right now, mobile computing is the leading market driver. TSMC has been helping the industry produce comprehensive, powerful mobile computing devices.

The future growth drivers and trends include mobile computing, cloud computing and smart devices. However, technical and economic challenges also lie ahead. TSMC has been pushing the lithography roadmap. 28nm is said to be the limit of conventional single-patterning lithography. TSMC has innovations to extend immersion to 20nm. The next-generation lithography (NGL) is being preferred beyond 20nm. Also, EUV and multiple-e-beam concept and feasibility has been proven. The more than 10x throughput gap requires collaborative innovation and funding.

TSMC continues to invest in R&D for transistor architecture trends. There is increasing technology complexity, as reflected by mask layers increase. The technology shrink also leads to design complexity.

There are challenges such as intrinsic wafer cost parity and uncertain technology migration ROI. TSMC’s mission is to be the trusted technology and capacity provider for the global logic IC industry for years to come. TSMC already has capacity leadership. TSMC’s total 12″ cleanroom space will equal more than 32 World Cup football fields by the end of this year..

TSMC customers’ expectations include the offer of leading-edge technology, continue to expand capacity, enable faster time to market, faster technology ramp up, faster manufacturing cycle times, and lower cost /die. To bridge the cost and productivity gap, TSMC no longer maintains cost/transistor trend by 2018 due to the slowing pace of technology shrink, and increasing technology complexity.


The 450mm promise!
As of today, the move to a 450mm fab promises opportunities for more efficient capacity expansion, faster technology ramp up, faster manufacturing cycle times, and higher land and people productivity.

There are certain challenges associated with the transition to 450mm fabs. One. there is need for a viable photolithography technology that meets N10 requirements by 2015. Next, there is need for reasonable tool cost parity that enables the expected 450mm cost advantages.  Besides, there are the other usual challenges such as significant productivity improvement, fully automated (unmanned) fab operation, need for smart tools (self calibrated, self control, virtual metrology) and green fabs.

Many innovations enabled 300mm transition with great productivity and engineering improvements. For instance, a look at the production indices summary for 300mm fabs vs. 200mm fabs indicate 0.8X cycle time improvement, 0.4X defect density improvement, people productivity going up 2.5X, while equipment productivity went uo 1.8X. The industry also moved on to full automation rate at 300mm.

450mm will further stimulate industry innovations. Those would be similar to the many innovations that enabled 300mm excellence, such as single wafer process, twin-scan, multi-chambers, equipment automation, advanced APC/AEC, automated material handling system, etc. TSMC believes that many more innovations are coming up for 450mm. New equipment platform will also provide significant productivity improvement through continuous innovations.

KPI goals for 450mm tools vs. 300mm include:
* Overall equipment efficiency: 1.1x (2018) -> 1.8x (2022).
* Tool price: Less than 1.4X.
* Footprint: Less than 1.5X.
* Defect density: Less than 0.4X.
* Power and water consumption/wafer: 1X.

One can control wafers in foundry fabs by excessive monitoring wafers. Smart tools are required to reduce the monitoring wafers (self monitoring, self control and virtual metrology).

There will also be fast technology ramp up. Tool’s hardware matching can be in areas of MFC, fluid flow field, thermal profile, RF power matching, electrical field and electron density (r,Θ,z), respectively. The question is: can hardware matching eliminate process matching? There is a need to pursue green manufacturing. The IC manufacturers should work with equipment/material suppliers for eco-friendly design and green manufacturing.