Kumar, Rajesh Chauhan, Vishnu Koratkar, N. Kumar, Shalendra Sharma, Aditya Chae, K.-H. Won, S.O. 2024-01-19T17:02:00Z 2024-01-19T17:02:00Z 2021-09-02 2020-08 0925-8388 https://pubs.kist.re.kr/handle/201004/118312 Modifications and resulting changes in various properties of nanocrystalline HfO2 high-k dielectric thin films with nominal thickness of 20 nm grown by atomic layer deposition technique on silicon and glass substrates were investigated as a function of swift heavy ions (SHI) irradiation. In the present work, our attention is to study the electronic excitation induced modifications in HfO2 thin films cause of formation of defects by 120 MeV Au9+(SHI) irradiation. For the same purpose, the annealed (500 °C) HfO2 thin films were irradiated with the varying fluence in the range of 1E11 to 1E13 ions/cm2. The virgin and irradiated representative HfO2 thin films were investigated by various techniques. The substantial root mean square (RMS) surface roughness (0.5？1 nm) and variation in grain size (40？52 nm) as a function of Au9+ ions irradiation were determined using atomic force microscope (AFM). The optical properties of HfO2 thin films were analyzed by measuring absorbance and transmission (54？62%) spectra in 200？700 nm wavelength range followed by calculation of optical band gap (Eg). The photoluminescence (PL) spectra obtained at excitation wavelength 220 nm indicate the formation of defects due to SHI irradiation. A change in excitation wavelength (220？260 nm) causes the shift in emission peaks towards higher wavelength. Structural investigations have been carried by Grazing Incidence X-ray Diffraction (GIXRD) techniques which reveal the variation in crystallite size as a function of different fluence. The results of a systematic XPS study of virgin and SHI irradiated samples shows the shifting of Hf 4f and O 1s peaks towards lower binding energy as compared to virgin sample. O K-edge XANES were performed to understand the ion-beam irradiation induced defect formation and their consequences on the electronic structure of HfO2 thin films. The obtained peaks in Rutherford backscattering spectrometry (RBS) affirm the existence of Hf and O elements and width of the peaks determine the sample thickness (20 nm). ？ 2020 Elsevier B.V. English Elsevier Ltd Influence of high energy ion irradiation on structural, morphological and optical properties of high-k dielectric hafnium oxide (HfO2) thin films grown by atomic layer deposition Article 10.1016/j.jallcom.2020.154698 1 Journal of Alloys and Compounds, v.831 Journal of Alloys and Compounds 831 N scie scopus 000531725700008 2-s2.0-85081894127 Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metallurgy & Metallurgical Engineering Article Atomic layer deposition Binding energy Crystal atomic structure Crystallite size Electronic structure Energy gap Hafnium oxides Heavy ions High-k dielectric Ion beams Ion bombardment Nanocrystalline silicon Nanocrystals Optical properties Oxide films Radiation Rutherford backscattering spectroscopy Semiconductor quantum wells Substrates Surface roughness X ray photoelectron spectroscopy Grazing-incidence X-ray diffraction HfO2 High-energy ion irradiation Photoluminescence spectrum Root mean square (rms) surface roughness Rutherford backscattering spectrometry UV-Vis XANES Thin films AFM ALD HfO2 Ion beam PL UV-Vis. XANES and RBS XPS XRD