Search

Ferroelectric-based electronic devices have excellent low-energy characteristics due to the highly insulating property, in which the Joule heating can be neglected. The recent discovery of electrically switchable cracks in ferroelectric/alloy film heterostructure gave rise to a new way to construct transistor, where the opening and closing of crack switched the channel current off and on. Here, we observed the complementary switching of cracks for the first time, and demonstrated a complementary inverter without any additional process to set different types of transistors, which was implemented by forming the n- and p-type transistor in conventional complementary metal oxide semiconductor (CMOS) technology. The complementary states were generated spontaneously once the cracks were induced and varied with the change of applied input voltage polarity. The low ON resistance and near-zero OFF state leakage current result in the high current on/off ratio (~107) and allow for the low dynamic and static power dissipation. Further, the switching of cracks is coupled to the surrounding ferroelectric polarization states, offering the non-destructive readout operation. We believe that our work provides a very simple route to build complementary logic gates and paves a way for the energy-efficient electronic devices, while promoting the "crack nanoelectronics". Image 1 • The concept of complementary ferroelectric-nanocrack logic has been proposed and experimentally demonstrated for the first time. • The switchable cracks controlled by electric field show high on/off ratio and ultralow power consumption. • The complementary property is implemented without any process to set the polarities of transistors. • A complementary logic with nonvolatility is demonstrated. • Phase-field simulation is used to explain the switching process of crack. [ABSTRACT FROM AUTHOR]

The lack of robust interphases between carbon and most metals prevent the exploration of the full scope potential of carbon-based metal matrix composites. Here, we demonstrated a scalable and straightforward way to produce strong interphase between copper (Cu) and carbon fibers (CFs) by designing a tailored titanium oxide-carbide coating (TiO y -TiC x) on CFs in a molten salt process. The oxide-carbide composition in the graded layer strongly depends on the coating temperature (800–950 °C). A coating with a high TiO y content obtained at a low coating temperature (800 °C) contributes to better molten-Cu wetting and strong adhesion energy between CFs and Cu during a subsequent exposure at 1200 °C. The Cu wetting angle for the TiO y -TiC x -CF sample obtained at 800 °C was ∼80° ± 5° with a Cu surface coverage of ∼50% versus ∼115° and ∼10% for the TiC x -CF sample made at 950 °C. The kinetic analysis of the coating process step by step suggests a growth rate limited by the mass-transfer through the coated layer. This method provides a novel approach to improve the thermal conductivity of Cu/C composite for thermal management applications. Image 1 [ABSTRACT FROM AUTHOR]