Research News: In microelectronics, copper conductors and Teflon substrates are the materials of choice in many-applications due to the high conductivity of copper and the low dielectric constant of Teflon. The nature of Teflon, however, results in low adhesion strength, which makes a multi-step Cu-deposition process necessary. Here, an alternative, selective CVD, which can produce smaller feature sizes and reduces the need for wet etching, is presented and explained.