Preparation of rare earth CeO2 thin films using metal organic decomposition method for metal-oxide–semiconductor capacitors

• Published in: Journal of materials science. Materials in electronics Vol. 28; no. 17; pp. 12503 - 12508
• Main Authors: Agrawal, Khushabu S., Patil, Vilas S., Khairnar, Anil G., Mahajan, Ashok M.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-09-2017; Springer Nature B.V
• Subjects: Atomic force microscopy; Beryllium; Capacitors; Cerium oxides; Characterization and Evaluation of Materials; Chemistry and Materials Science; Cross-sections; Decomposition; Electric contacts; Electrical measurement; Electron beams; Electron spin; Emission spectroscopy; Evaporation; Field emission microscopy; Fourier transforms; Gold; Infrared spectroscopy; Materials Science; Metal oxide semiconductors; Optical and Electronic Materials; Rare earth compounds; Resistance; Scanning electron microscopy; Silicon substrates; Sol-gel processes; Spectrum analysis; Spin coating; Thin films; Work Function; CeO2; Complementary Metal Oxide Semiconductor; Leakage Current Density; Flat Band Voltage
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-017-7072-6

Investigation of metal organic decomposed rare earth cerium oxide thin films deposited on Si substrate by sol–gel spin coating technique was carried out. The structural properties have been examined by using XRD, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The XRD confirms the cubic phase of CeO
2
thin films with (111) plane observed at 28.54°. The FTIR and EDAX spectra confirm the formation of CeO
2
films with atomic percentage of 19.39 and 54.82% of Ce and O
2
, respectively. Thickness of 60.11 nm of CeO
2
film measured by cross sectional FESEM image, the average roughness of ~0.6 nm of 400 °C annealed CeO
2
films were observed from AFM micrograph. The MOS capacitors were fabricated by using Ti/Au bilayer metal contact depositing by E-beam evaporator on CeO
2
/Si thin film for electrical measurements. Capacitance and conductance voltage measurement was carried out to determine the effective oxide charges (Q
eff
), interface trap density (D
it
) and dielectric constant (k) and are 2.48 × 10
12
 cm
−2
, 1.26 × 10
12
 eV
−1
cm
−2
and ~39, respectively. The effective metal work function of 5.68 for Ti/Au bilayer is observed to be higher than the work function of Ti or Au metals in vacuum.