MICRO:Industry News:Lead (Nov/Dec '98)

Unlike their counterparts in the semiconductor industry, MEMS manufacturers face their most challenging contamination problems at the back-end of the process. Solving those problems is a key step on the industry's path to reaching the multibillion-dollar potential of the market for the technology, say several participants in a recent microelectromechanical systems commercialization conference. Although manufacturers "don't need things as clean as the new ultracleanrooms for 1-Gb DRAMs, we do need clean, and at further levels out in the process than ICs do," points out Karen Markus, director of the MEMS Technology Application Center at the Microelectronics Center of North Carolina (MCNC) in Research Triangle Park. MEMS devices lack the "density of features" that chips acquire during lithography, etching, and deposition. Hence, Markus continues, "a particle that will kill a DRAM, unless it is absolutely perfectly placed, would be of less concern to a MEMS device. TESTING: Danelle Tanner of Sandia National Laboratories tests MEMS reliability using the SHiMMeR, a tool developed at the lab. Images at right show MEMS pin joint holes in unstressed and stressed conditions. Photo by Randy Montoya; Images Courtesy of Sandia National Laboratories "ICs are less sensitive to the environment once the cleanroom process is done. And then you go to the release, dicing, packaging, and assembly stage for MEMS, and particulate contamination becomes ultrasensitive to us. It's the flip side of the IC industry." MEMS is "an emerging industry. . . that's still trying to define itself," asserts Kenneth R. Farmer II, director of the Microelectronics Research Center at the New Jersey Institute of Technology (NJIT) in Newark. "In addition to being in its infancy, an additional problem