(Invited) A Metal Oxide Antifuse-Diode Device

Crystalline metal oxides have been used in various micro and nano electronics and optoelectronics, such as conductors, superconductors, and light emitting devices (LEDs). The amorphous metal oxide dielectric is usually a high-k material suitable for the insulation purpose. The doped metal oxide, such as the Zr-doped HfO₂ (ZrHfO), high-k thin film has many advantageous material and electrical properties, such as the high crystallization temperature, low interface layer thickness in contact with Si, and low interface density of states (1). When nanocrystals are embedded into the high-k metal oxide dielectric thin film, electrons and charges can be stored for a long period of time, which is suitable for the nonvolatile memory application (2). Recently, it was proved by the author’s group that the broad band white light could be emitted from the metal oxide dielectric thin film after the dielectric breakdown due to the thermal excitation of the nano size conductive paths (3). In this talk, a new high-k dielectric based device that shows both antifuse and diode functions is reported. Figure 1 shows a large “programmed” to “unprogrammed” leakage current ratio of 10⁵ is obtained from an original MOS capacitor made of a high-kgate dielectric on a p-type wafer, which fits the antifuse requirement. Figure 2 shows that for a same device in the programmed state, the leakage current increases with the increase of the magnitude of the gate voltage in the negative voltage range. However, the leakage current remains low and changes little over a large range of gate voltage in the positive voltage range, which is similar to the diode behavior. On the other hand, the leakage current-voltage curve of the new device is almost linear while that of the conventional diode follows the exponential relationship. The operation physics, structure, and material properties of the new device will be discussed in detail.   

1. Y. Kuo, J. Lu, S. Chatterjee, J. Yan, H. C. Kim, T. Yuan, W. Luo, J. Peterson, and M. Gardner, “Sub 2 nm Thick Zirconium Doped Hafnium Oxide High-K Gate Dielectrics,” ECS Trans., 1(5), 447-454 (2006).
2. Y. Kuo, invited, “Nanocrystals Embedded High-k Nonvolatile Memories – bulk film and nanocrystal material effects,” ECS Trans., 53(4), 121-128 (2013).
3. Y. Kuo, invited, “A Solid State Thin Film Incandescent Light Emitting Device,” Proc. IDEM, 104-107 (2014).