From the Solid State Laboratory to Ziptronix: Microelectronics Research at RTI

How RTI helped fuel the integrated circuit boom

Microelectronics–the devices, fabricated in submicron dimensions, that form the basis of all electronic products– has been an area of primary research at RTI since the Institute's earliest days. In 1962, RTI's Solid State Laboratory was at the forefront of revolutionary developments in integrated circuitry–complex circuits etched onto tiny chips of semiconductor material. And in the 1970s, RTI's Center for the Synthesis and Study of Semiconductor Compounds endeavored to develop smaller, lighter-weight materials surpassing silicon in speed, frequency, and power. In collaboration with North Carolina State University, the Center designed and built the world's first monolithic cascade solar cell, which doubled the efficiency of conventional silicon solar cells.

In 1983, RTI broke ground on a 47,000-square-foot building, named for RTI's first president, George R. Herbert, to house its semiconductor materials research and device fabrication. This "custom integrated circuit foundry," as it was technically called, fabricated on the order of 1,000 semiconductor wafers each year. RTI researchers were soon considered among the best in the world at growing single-crystal diamonds and other semiconductor materials faster, thinner, and in greater volume for military, avionic, and space applications. 3M was among the fabrication laboratory's first clients, funding a project to make synthetic diamond coatings for the optics, electronics, and machine tools industries. Clients for RTI's fabricated nickel-chromium resistors, metal capacitors, light-emitting diodes, and lasers included Sumitomo and Sandia National Laboratories.

A decade later, RTI patented its innovative ZiROC room-temperature, adhesive-free bonding technology, which makes it possible to fuse and electrically interconnect silicon wafers and thus manufacture chips that are faster, smaller, lighter-weight, and more powerful than existing circuits. The Institute's experience with microelectronics and semiconductor materials really paid off in 2000, when part of its integrated circuit chip production facility was spun off into a private company called Ziptronix, Inc., which builds 3-D integrated circuits using ZiROC technology. Ziptronix secured $6.5 million in venture capital funding in 2001, and was soon fabricating chips for Motorola, Northrup Grumman, and other major companies.