Jan. 14, 2003 — As computer chip components continue to shrink into the nanoscale, their smaller dimensions and complexity have created a growing demand for nanoparticles in the chemical-mechanical polishing (CMP) phase of the chip-making process.
Mindy Rittner, a senior industry analyst with Business Communications Co. Inc., which organized a conference on nanoparticles last October, cited CMP as one of the hottest and most immediate markets for nanoparticles.
She said the market for chemical-mechanical polishing slurries, the mixture of liquid chemicals and nanoparticles used to process silicon chips, hard drive disks and optical lenses, today is a $440 million business growing more than 20 percent a year. Experts estimate that nanoparticles make up about 25 percent of that market value.
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While it may not sound sexy, nanoparticle-enhanced CMP is critical for advanced chip-making. Computer chips are made by depositing multiple layers of materials in elaborate patterns. After each layer is deposited on a silicon wafer, it must be planarized, or made very flat, and polished to create a defect-free surface. Hard disk drives also require a precisely flat, mirror-smooth finish.
The CMP slurry flattens and smoothes a layer’s surface through a combination of chemical reactions and physical abrasion. The slurry is typically applied with a polishing pad the same size as the wafer.
Rittner, who holds a Ph.D. in materials science and engineering from Northwestern University, reported that “nanoparticles are absolutely critical” to the CMP process. Cabot Microelectronics Corp. and Rodel Inc. are the two leading suppliers of CMP slurries to the semiconductor industry, which uses millions of gallons of abrasive polishing liquid every year.
Other players include DuPont AirProducts NanoMaterials LLC, a joint venture between DuPont and Air Products and Chemicals Inc., Alcoa World Chemicals Inc., Hitachi Chemical Co. Ltd. and Nanophase Technologies Corp. of Romeoville, Ill.
“At chip geometries below about 0.25 micron, CMP becomes essential to IC fabrication,” Rittner said. These mixtures “must have nanoscale abrasive particles to ensure that each layer in a chip is flat, smooth and free of defects.”
CMP slurries with nanoparticles are needed not only because chips are being built with smaller circuitry, but also because they are being fabricated in more layers and with a wider range of metal, dielectric and oxide materials.
Rittner predicts that by 2005 the global market for “nanoparticle applications that have emerged in recent decades” will grow to $900 million, with CMP comprising the largest segment. In 2001 that market for raw nanopowders was about $555 million.
According to Rittner, nanoparticles of silica, alumina, ceria and other materials are needed for new industrial recipes to meet the growing spectrum of polishing and planarizing applications. An important trend is the shift from aluminum interconnects to copper wiring. She also said that CMP will grow because an increasing percentage of chip wafers will require nanoscale planarization.
As Douglas Moffat of NanoTech Financing Solutions LLC in Atlanta sees it, the CMP market is an important new play for small tech business. “The nanoparticles industry is finally securing a high value-added market opportunity,” he said. “Early attempts to crack this field were limited by inconsistent particle size distributions. New production techniques and improved process control are facilitating this commercialization.”
Nanophase is already supplying Rodel with two kinds of nanoparticles for semiconductor polishing. The company reported in October that the first material is performing significantly better than existing products in tests. Nanophase also reported that it anticipates Rodel to begin production testing with a major semiconductor manufacturer in the fourth quarter.
Dan Bilicki, Nanophase’s vice president of sales, said that forming a strategic partnership with Rodel was important because the CMP business is large and technically complex, involving closely guarded relationships with the big chip makers.
Don Freed, vice president of business development for Nanophase, added that through Rodel, “we’ve learned that we couldn’t have entered this market successfully on our own. The barriers to entry, including the cost of clean rooms and process equipment, are too high.”
The two executives declined to discuss the types or quantities of nanoparticles Nanophase is supplying to Rodel. They did say that the materials are provided in liquid dispersions, which are then formulated by Rodel into chemical slurries. Rodel is owned by Rohm and Haas Co., a maker of specialty chemicals and electronics materials with more than $5 billion in sales.