Temperature Effects on Charge Transfer Mechanisms of nc-ITO Embedded ZrHfO High-k Nonvolatile Memory Devices

2011 ◽  
Vol 1337 ◽  
Author(s):  
Chia-Han Yang ◽  
Yue Kuo ◽  
Chen-Han Lin ◽  
Way Kuo
Keyword(s):  
Gate Voltage ◽  
Nonvolatile Memory ◽  
Charge Retention ◽  
Mos Capacitors ◽  
Dielectric Thin Film ◽  
High K ◽  
Nonvolatile Memory Devices ◽  
High K Dielectric ◽  
Voltage Region ◽  
Large Charge

ABSTRACTThe nanocrystalline ITO embedded Zr-doped HfO2 high-k dielectric thin film has been made into MOS capacitors for nonvolatile memory studies. The devices showed large charge storage densities, large memory windows, and long charge retention times. In this paper, authors investigated the temperature effect on the charge transport and reliability of this kind of device in the range of 25°C to 125°C. The memory window increased with the increase of the temperature. The temperature influenced the trap and detrap of not only the deeply-trapped but also the loosely-trapped charges. The device lost its charge retention capability with the increase of the temperature. The Schottky emission relationship fitted the device in the positive gate voltage region. However, the Frenkel-Poole mechanism was suitable in the negative gate voltage region.

Reliability of nc-ZnO Embedded ZrHfO High-kNonvolatile Memory Devices Stressed at High Temperatures

2009 ◽  
Vol 1160 ◽  
Author(s):  
Chia-Han Yang ◽  
Yue Kuo ◽  
Chen-Han Lin ◽  
Way Kuo
Keyword(s):  
Nonvolatile Memory ◽  
Breakdown Strength ◽  
Memory Studies ◽  
Memory Window ◽  
Charge Retention ◽  
Mos Capacitors ◽  
High K ◽  
Large Memory ◽  
The Difference ◽  
Large Charge

AbstractThe nanocrystalline ZnO embedded Zr-doped HfO2high-kdielectric has been made into MOS capacitors for nonvolatile memory studies. The device shows a large charge storage density, a large memory window, and a long charge retention time. In this paper, authors investigated the temperature effect on the reliability of this kind of device in the range of 25°C to 175°C. In addition to the trap-assisted conduction, the memory window and the breakdown strength decreased with the increase of the temperature. The high-k film's conductivity increased and the nc-ZnO's charge retention capability decreased with the increase of temperature. The nc-ZnO retained the trapped charges even after the high-k film broke down and eventually lost the charges at a higher voltage. The difference between these two voltages decreased with the increase of the temperature.

Nonvolatile memory MOS capacitors made of CdSe embedded ZrHfO high-k gate dielectric

2013 ◽  
Vol 1562 ◽  
Author(s):  
Chi-Chou Lin ◽  
Yue Kuo
Keyword(s):  
Gate Voltage ◽  
Coulomb Blockade ◽  
Nonvolatile Memory ◽  
Gate Dielectric ◽  
Stress Test ◽  
Charge Trapping ◽  
Differential Resistance ◽  
Mos Capacitors ◽  
Mos Capacitor ◽  
High K

ABSTRACTMOS capacitor composed of nc-CdSe embedded ZrHfO high-k gate dielectric stack was fabricated and characterized for nonvolatile memory functions. Detailed material and electrical properties have been investigated. With a large charge trapping capability, this kind of device can trap electrons or holes depending on the polarity and magnitude of the applied gate voltage. For the same stress time, the device trapped more holes than electrons under the same magnitude of gate voltage but different polarity. The negative differential resistance peak was observed at the room temperature due to the Coulomb blockade effect. The charge trapping mechanism was delineated with the constant voltage stress test. After 10 years of storage, about 56% of trapped charges still remain in the device.

Relaxation Behavior and Breakdown Mechanisms of Nanocrystals Embedded Zr-doped HfO2 High-k Thin Films for Nonvolatile Memories

2008 ◽  
Vol 1071 ◽  
Author(s):  
Chia-Han Yang ◽  
Yue Kuo ◽  
Chen-Han Lin ◽  
Rui Wan ◽  
Way Kuo
Keyword(s):  
Nonvolatile Memory ◽  
Storage Capacity ◽  
Breakdown Strength ◽  
Charge Storage ◽  
Leakage Currents ◽  
Low Leakage ◽  
Nonvolatile Memories ◽  
High K ◽  
Memory Characteristics ◽  
Large Charge

AbstractSemiconducting or metallic nanocrystals embedded high-k films have been investigated. They showed promising nonvolatile memory characteristics, such as low leakage currents, large charge storage capacities, and long retention times. Reliability of four different kinds of nanocrystals, i.e., nc- Ru, -ITO, -Si and -ZnO, embedded Zr-doped HfO2 high-k dielectrics have been studied. All of them have higher relaxation currents than the non-embedded high-k film has. The decay rate of the relaxation current is in the order of nc-ZnO > nc-ITO > nc-Si > nc-Ru. When the relaxation currents of the nanocrystals embedded samples were fitted to the Curie-von Schweidler law, the n values were between 0.54 and 0.77, which are much lower than that of the non embedded high-k sample. The nanocrystals retain charges in two different states, i.e., deeply and loosely trapped. The ratio of these two types of charges was estimated. The charge storage capacity and holding strength are strongly influenced by the type of material of the embedded nanocrystals. The nc-ZnO embedded film holds trapped charges longer than other embedded films do. The ramp-relax result indicates that the breakdown of the embedded film came from the breakdown of the bulk high-k film. The type of nanocrystal material influences the breakdown strength.

scholarly journals Functional Oxide as an Extreme High-k Dielectric towards 4H-SiC MOSFET Incorporation

2017 ◽  
Vol 897 ◽  
pp. 155-158 ◽  
Author(s):  
Stephen A.O. Russell ◽  
Michael R. Jennings ◽  
Tian Xiang Dai ◽  
Fan Li ◽  
Dean P. Hamilton ◽  
...  
Keyword(s):  
Thin Film ◽  
Perovskite Phase ◽  
Buffer Layers ◽  
Mos Capacitors ◽  
Lattice Match ◽  
Polarization Voltage ◽  
High K ◽  
Buffer Material ◽  
High K Dielectric ◽  
Accumulation Region

MOS Capacitors are demonstrated on 4H-SiC using an octahedral ABO3 ferroic thin-film as a dielectric prepared on several buffer layers. Five samples were prepared: ABO3 on SiC, ABO3 on SiC with a SiO2 buffer (10 nm and 40 nm) and ABO3 on SiC with an Al2O3 buffer (10nm and 40 nm). Depending on the buffer material the oxide forms in either the pyrochlore or perovskite phase. A better lattice match with the Al2O3 buffer yields a perovskite phase with internal switchable dipoles. Hysteresis polarization-voltage loops show an oxide capacitance of ~ 0.2 μF/cm2 in the accumulation region indicating a dielectric constant of ~120.

Nonvolatile Memory Characteristics Induced in High-k Dielectric Thin Films through Electron Irradiation

2011 ◽  
Vol 59 (2(2)) ◽  
pp. 726-729 ◽  
Author(s):  
Chan-Rock Park ◽  
Hong-Kyoung Lee ◽  
Jin-Ha Hwang ◽  
Young-Hwan Hahn ◽  
Byeong-Cheol Lee ◽  
...  
Keyword(s):  
Thin Films ◽  
Electron Irradiation ◽  
Nonvolatile Memory ◽  
Dielectric Thin Films ◽  
High K ◽  
High K Dielectric ◽  
Memory Characteristics
Sign in / Sign up

Export Citation Format

Share Document