Leveraging collaborations to drive down the LED cost curve
ATMI, Inc., Tempe, AZ USA
For many years, IDMs, OEMs and materials suppliers in the semiconductor industry have faced the increasingly difficult challenges of device scaling by sharing knowledge with one another and combining their respective skill sets in a collaborative environment. While these collaborations often bring their own challenges from a commercial and cultural standpoint, there is no doubt that technical benefits have helped the industry continue down the performance and cost path laid out several decades ago by Gordon Moore. Well-known examples of collaborative efforts that have delivered valuable solutions to the industry abound in almost every module application, especially those of lithography, CMP, deposition and plating. Consortia, such as SEMATECH, imec, etc., have also proven to be effective models.
The LED industry, although decades old, has only seen explosive growth over the past few years with increasing demand for display backlighting and solid-state lighting (SSL). To support the performance and cost-reduction roadmap dictated by Haitz's Law (LED's version of Moore's Law), it's likely that the industry will need to incorporate many of the same methodologies utilized by its more mature brethren. In conversations with key market players, it is clear that while some of the best known methods of the semiconductor industry have found their way into the LED industry, numerous opportunities for improvement still exist. In fact, many industry observers have expressed that they believe the most accessible cost-reduction opportunities have already been harvested, such as migrating to larger wafer sizes, maximizing use of commodity materials, etc., and that further improvements will take significantly more effort.
If we think of any collaborative effort as a group of somewhat overlapping sets of competencies ??? a Venn diagram if you will ??? then the areas of overlap should highlight the best opportunities for collaboration to realize significant technological breakthroughs. For example, equipment manufacturers have a set of capabilities, let's call them "levers," which they can utilize to adjust and optimize hardware performance. These may include flow rates, chamber design, materials of construction, temperature control and many others. Similarly, materials suppliers have their own unique set of levers that they can adjust to modify and optimize their materials, including stoichiometry, viscosity, reactivity and many others. If the respective Venn diagrams for these levers can be combined such that the collaboration exploits the advantages of the overlapping capabilities, optimized solutions can be delivered to end users. Of course, the end-user IDMs typically bring their own key levers, most critically in the area of process integration.
As a strong proponent of collaborative engagements, ATMI often refers to delivering "process efficiency" to customers. While these activities may include reducing price over time as scale and other factors allow, more often than not they focus on joint development activities with a device and/or an equipment maker to drive process improvements that lead to higher yields, increased throughput, and/or less non-value-added steps. A promising example of an opportunity for innovation through collaboration in the LED industry is around epitaxial deposition processes.
The U.S. Department of Energy, in a recent report on the SSL industry, highlighted MOCVD processes as a key area for improvement. The yield and throughput of the MOCVD process has a significant impact on final LED device cost. Methodologies utilized by the semiconductor industry to improve their process efficiency, many originally driven by collaborative efforts, include improvements in stoichiometric control of reactants, improved flux stability, increased material utilization, and reduced downtime through the use of bulk material delivery.
Solving difficult technology challenges is often best, and sometimes only, achieved through concerted efforts by partners who combine their respective capabilities to deliver more value than the sum of the parts. As the LED industry matures, it seems exceedingly likely that many of the future breakthroughs in performance and cost will come through collaborative engagements.
Jeff Desroches is Business Development Manager at ATMI, Inc., 2151 East Broadway Road, Suite 101, Tempe, AZ 85205, 480-736-7600, firstname.lastname@example.org
Solid State Technology, Volume 54, Issue 8, August/September 2011