The Semi companies all have their own super-secret development plans,” observes Tracey Jacksier, director of Air Liquide’s Analytical Sciences Core Global Lab. “Now they’re looking at new gases that weren’t even on the list 15 years ago.” Not just novel gases, but, increasingly, new liquid chemicals are coming into play as Semi’s major fabs move to 20nm and lower technology nodes, and prepare for the vast paradigm shift to 450mm wafers. As ‘Moore’s Law’ predicts, the number of transistors on a chip will double approximately every two years.
Accordingly, Jacksier and her rivals are engaged in a vigorous, highly competitive race to find viable, economic means of analysis to keep pace with emerging requirements, ranging from the adoption of sulfur-containing gases to the enhanced hydrogen purity needed for EUV (extreme ultraviolet) lithography, to the development of new organometallics to the growing use of germane and barrier level films.
Much of the work is transpiring on the raggedy edge of invention, where hazards abound, and analytical resources and expertise are limited. Indeed, there is a sizable gap between the capabilities of even the most advanced commercial analyzers and the emerging needs of an industry in rapid transition.
“Technology must evolve to include the ability to analyze liquids at the same level and detail that you analyze gases,” remarks Michael A. Pikulin, the senior vice-president for Business & Technology Development at Voltaix LLC. “At DuPont they don’t think of chemicals in terms of ‘5 nines’ (99.999 percent) and ‘6 nines’ (99.9999 percent), but Semi requirements call for that.”
Technology must evolve to include the ability to analyze liquids at the same level and detail that you analyze gases
Today, materials makers and their analytical suppliers enjoy a myriad of opportunities, with so many new applications and technologies coming to the fore. Jacksier notes, “As the industry changes, you always need people to think outside the box.”
Taking stock of where we are
Within the world’s leading fabs, an almost preternatural calm belies the intense effort that goes into maintaining a consistently stable and immaculately clean environment for the production of their delicate chips. Laser-based analyzers, such as those based on Tiger Optics’ Continuous Wave Cavity Ring-down Spectroscopy (CW CRDS), are used for moisture, oxygen and, increasingly, methane detection. So versatile, cost-effective and powerful are the new generation of analyzers that they have fundamentally changed the way measurements are conducted.
By contrast, traditional techniques, whether FTIR, Raman, electrochemical, quartz-crystal oscillator or gas chromatography suffer variously from severe limitations, be they cost, drift, interferences, operational complexity or truncated dynamic range.
Typically, advanced spectroscopic analyzers offer a multitude of advantages that include:
Time waits for no-one
Nonetheless, when it comes to evolving Semi processes, there are key points where even the most advanced new commercial analyzers fall short. As the specialty gas companies evolve as specialty chemicals suppliers, they are under growing pressure to meet increasingly stringent specifications on new and exotic materials.
Our research points to the growing need for matching instrumentation that addresses the following critical needs:
Faced with such challenges, developers of new gases and chemicals must improvise.
“ ‘I don’t feel like doing it’, is never an answer,” states Jacksier. For now, she and her competitors often find themselves contending with analytical technologies that are at a pre-commercial phase, when - in her words - “The user needs to do more because they’re new, and the vendor hasn’t been able to figure everything out yet.”
For experimentalists and makers of advanced spectroscopic instruments alike, the operative word is ‘yet’.