Liquid Embossing Process for Silicon Chips

Silicon chip manufacturing can be a costly proposition; the most prevalent method, photolithography (or optical lithography), offers precision but is an expensive process requiring several steps, pricey equipment and extremely clean operating facilities. It’s no surprise then that researchers are constantly searching for new ways to fabricate chips as the demand for these electronics components continues to skyrocket around the world.

Eric J. Wilhelm and Colin Bulthaup developed a novel fabrication method that can be used in place of optical lithography for some types of chips. They invented a liquid embossing process that uses a rubber stamp and inorganic inks while pursuing engineering degrees at the Massachusetts Institute of Technology in 1999.

Wilhelm was born in Rochester, New York, in 1977. Bulthaup is a Los Angeles native, born in 1976. The two crossed paths when they began working on a joint project under Professor Joseph M. Jacobson of the MIT Media Lab's Nanomedia research group. Wilhelm earned his SB, SM and Ph.D., all in Mechanical Engineering, completing his studies at MIT in 2004; Bulthaup earned SB and SM degrees in Electrical Engineering and Computer Science.

The pair was part of a team looking into printing techniques for patterning nanocrystal colloids using ink, an inking plate and a stamp. Bulthaup realized that if he looked closely at the inking stamp they were using, he could see that the stamp pattern had been embossed on its surface. He and his colleagues began examining the possibility of using a liquid embossing system to directly print patterns of inorganic semiconductors on chips. Over two years of development, they were able to improve the process to make it rapid, clean, cheap and applicable to a wide range of materials. The technique is able to fabricate features as small as 70 nanometers, and, as it requires no etching, it is relatively inexpensive. In 2001, Wilhelm and Bulthaup were honored with the U.S. Patent Office’s Collegiate Inventor's Award for the printing technique, for which they were awarded U.S. Patent No. 6,517,995.

Upon completion of his studies that year, Bulthaup founded Kovio, Inc  in Sunnyvale, Calif., to commercialize the liquid embossing process and to develop new patterning and ink technologies. At Kovio, Bulthaup held the title of Director of Engineering until 2003, when he rejoined Wilhelm and three others -- Saul Griffith, Dan Goldwater and Ryan McKinley  -- to form Squid Labs, an engineering design firm, where, like Wilhelm, he is a co-founder and General Partner.

Recognized by Wired Magazine  as the Best Industrial Design Firm of 2006, Emeryville, CA based Squid Labs has produced such attention-getting technologies as an electronic rope and autonomous swarm robots and has spun out numerous companies including Howtoons, Makani Power, OptiOpia and Instructables.

Bulthaup spun out another startup out of Squid Labs in 2006, called Potenco, Inc.. The company produces a pull-cord generator, or PCG, that has the ability to keep portable electronic devices working while providing independence from traditional power sources. By using the energy provided by a human user who simply pulls the cord, the PCG can charge portable batteries and power a variety of small electronics devices such as lights, cell phones, radios, PDAs and water purifiers. The PCG is commercially available. The company also provided its technology to Nicholas Negroponte’s One Laptop Per Child initiative.

Potenco plans to provide applications for both the developing and developed worlds.  Its aim is to help provide power to the millions of people around the world who have no access to electricity.

Meanwhile, Wilhelm serves as CEO and founder of Instructables, launched in 2005. The company offers a popular community web destination that allows for step-by-step collaboration among members to build a wide variety of projects, from how to cook paella to how to build a computerized Etch-a-Sketch. Users post instructions to their projects, with photographs, and interact through comment sections and forums.