Germanium Telluride (GeTe) phase change resistors for reconfigurable circuit applications

In this paper, we report on the electrical properties of the phase change (PC) material, Germanium Telluride (GeTe), and discuss the fabrication and testing of GeTe resistors. Vertical and horizontal GeTe resistors are fabricated and tested through resistance measurements before and after substrate heating and joule heating performed by voltage pulsing. Resistance changes of six orders of magnitude and four orders of magnitude are demonstrated by substrate heating and voltage pulsing, respectively. The horizontal resistor designs are shown to be impractical for low voltage applications due to the their large inter-electrode distances. Various sizes of GeTe resistors ranging from 15×15×0.4 μm3 to 3×3×0.09 μm3 are tested and a relationship is demonstrated between GeTe resistor length and the threshold voltage pulse required for phase change.