Companies maximise efficiency using 300 & 200mm wafers
Larger wafer diameters provide more chips per wafer at a modest increase in material and process costs, resulting in reduced chip costs. Historically, transitions to larger diameter wafers have provided cost reductions greater than 20% per unit area. However, enormous financial and technology hurdles continue to plague the development of, and the transition to, 450mm wafers.
As a result, the transition to larger diameter wafer has slowed dramatically and companies are maximising their efficiency using 300 and 200mm wafers. IC Insights’ Global Wafer Capacity 2015-2019 report shows that worldwide capacity by wafer size was dominated by 300mm wafers in 2014 and is forecast to continue increasing through 2019 (Figure 1).
Figure 1 - Forecast for wafer size shares of monthly installed capacity
Efforts to develop 450mm wafer technology continue to make some progress, but the pace of development slowed significantly in 2014. Now, by most accounts, volume production using 450mm wafers is not expected before 2020, although pilot production could start a year or two before. IC Insights shows 450mm wafers accounting for a very slim share of installed capacity in 2019.
For the most part, 300mm fabs are, and will continue to be, limited to production of high-volume, commodity-type devices (such as DRAMs and flash memories, image sensors and power management devices and complex logic and microcomponent ICs with large die sizes) and by foundries, which can fill a 300mm fab by combining wafer orders from many sources.
At the end of 2014, there were 87 production-class IC fabs utilising 300mm wafers (Figure 2). There are several 300mm R&D IC fabs and a few high-volume 300mm fabs around the world that make 'non-IC' products such as image sensors and discretes, but these are not included in the count shown in the chart.
Figure 2 - Number of IC fabs processing 300mm wafer
Only once - in 2013 - has the number of 300mm wafer fabs declined. That year, three large fabs operated by ProMOS and Powerchip closed and setbacks delayed the opening of several new 300mm fabs until 2014. By the end of 2019, there are expected to be 23 more 300mm wafer fabs in operation than there were at the close of 2014. The number of 300mm fabs will likely peak between 115-120, which assumes 450mm fabs will enter volume production in the future. For comparison, the greatest number of volume-production 200mm wafer fabs in operation was 210 (the number declined to 154 fabs at the end of 2014).
The list of companies with the most 300mm wafer capacity includes: memory suppliers Samsung, Micron, SK Hynix and Toshiba/SanDisk; the industry’s biggest IC manufacturer and dominant MPU supplier Intel; and the world’s two largest pure-play foundries TSMC and GlobalFoundries. These companies offer the types of ICs that benefit most from using the largest wafer size available to best amortise the manufacturing cost per die.
The number of fabs running 200mm wafers will continue to be profitable for many more years and be used to fabricate numerous types of ICs including speciality memories, display drivers, MCUs, analogue products and MEMS-based devices. Devices like these are practical to make in fully depreciated 200mm fabs that were used to produce devices now made on 300mm wafers. TSMC, TI and UMC remain the three companies with the greatest amount of 200mm wafer fab capacity.