Title :
Electrical characteristics of CeO2 buffer layer for a FRAM
Author :
Kim, Kyunghae ; Choi, Sukwon ; Kim, Sunghoon ; Roh, Yonghan ; Lee, Hoongjoo ; Jung, Donggeun ; Yi, Junsin
Author_Institution :
Sch. of Electr. & Comput. Eng., Sung Kyun Kwan Univ., Suwon, South Korea
Abstract :
The CeO2 films were formed on Si(111) substrate by radio frequency magnetron sputtering. Hysteresis was observed from the capacitance-voltage (C-V) characteristics of this sample. However, after the CeO2-Si structure was annealed under O2 ambient, the hysteresis almost disappeared due to SiO2 layer formation between CeO2 and Si. It is interesting that a counter-clockwise hysteresis loop was observed in the as-grown sample. On the other hand, a clockwise hysteresis loop was observed on the annealed sample. The annealed film showed high capacitance at accumulation due to the large dielectric constant, and a higher breakdown voltage due to the thin SiO2 layer. It was found that Poole-Frenkel emission and Schottky emission are the conduction mechanisms for annealed films. The CeO2/SiO2/Si structure was shown to be a legitimate candidate for FRAM device applications
Keywords :
MOS capacitors; annealing; capacitance; cerium compounds; electric breakdown; ferroelectric storage; leakage currents; permittivity; silicon; silicon compounds; sputter deposition; CeO2 buffer layer; CeO2-SiO2-Si; CeO2/SiO2/Si structure; DRAM; FRAM device applications; MIS capacitors; O2 ambient annealing; Poole-Frenkel emission; Schottky emission; Si; SiO2 layer formation; XRD; accumulation; breakdown voltage; capacitance-voltage characteristics; clockwise hysteresis loop; conduction mechanisms; counter-clockwise hysteresis loop; dynamic random access memory; high capacitance; large dielectric constant; leakage current mechanism; nonvolatile memory; radio frequency magnetron sputtering; Annealing; Capacitance; Capacitance-voltage characteristics; Clocks; Dielectric thin films; Electric variables; Hysteresis; Radio frequency; Sputtering; Substrates;
Conference_Titel :
Applications of Ferroelectrics, 2000. ISAF 2000. Proceedings of the 2000 12th IEEE International Symposium on
Conference_Location :
Honolulu, HI
Print_ISBN :
0-7803-5940-2
DOI :
10.1109/ISAF.2000.942400
