skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Dielectric properties of hydrogen-incorporated chemical vapor deposited diamond thin films.

Abstract

Diamond thin films with a broad range of microstructures from a ultrananocrystalline diamond (UNCD) form developed at Argonne National Laboratory to a microcrystalline diamond (MCD) form have been grown with different hydrogen percentages in the Ar/CH{sub 4} gas mixture used in the microwave plasma enhanced chemical vapor deposition (CVD) process. The dielectric properties of the CVD diamond thin films have been studied using impedance and dc measurements on metal-diamond-metal test structures. Close correlations have been observed between the hydrogen content in the bulk of the diamond films, measured by elastic recoil detection (ERD), and their electrical conductivity and capacitance-frequency (C-f) behaviors. Addition of hydrogen gas in the Ar/CH{sub 4} gas mixture used to grow the diamond films appears to have two main effects depending on the film microstructure, namely, (a) in the UNCD films, hydrogen incorporates into the atomically abrupt grain boundaries satisfying sp{sup 2} carbon dangling bonds, resulting in increased resistivity, and (b) in MCD, atomic hydrogen produced in the plasma etches preferentially the graphitic phase codepositing with the diamond phase, resulting in the statistical survival and growth of large diamond grains and dominance of the diamond phase, and thus having significant impact on the dielectric properties of thesemore » films.« less

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
946676
Report Number(s):
ANL/MSD/JA-60401
Journal ID: ISSN 0021-8979; JAPIAU; TRN: US200903%%563
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Appl. Phys.; Journal Volume: 102; Journal Issue: 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
08 HYDROGEN; 36 MATERIALS SCIENCE; ANL; CARBON; CHEMICAL VAPOR DEPOSITION; DETECTION; DIAMONDS; DIELECTRIC PROPERTIES; ELECTRIC CONDUCTIVITY; GRAIN BOUNDARIES; HYDROGEN; IMPEDANCE; MICROSTRUCTURE; MIXTURES; PLASMA; THIN FILMS

Citation Formats

Liu, C., Xiao, X., Wang, J., Shi, B., Auciello, O., Carlisle, J. A., Carpick, R., Adiga, V., Univ. of Wisconsin at Madison, and Univ. of Pennsylvania. Dielectric properties of hydrogen-incorporated chemical vapor deposited diamond thin films.. United States: N. p., 2007. Web. doi:10.1063/1.2785874.
Liu, C., Xiao, X., Wang, J., Shi, B., Auciello, O., Carlisle, J. A., Carpick, R., Adiga, V., Univ. of Wisconsin at Madison, & Univ. of Pennsylvania. Dielectric properties of hydrogen-incorporated chemical vapor deposited diamond thin films.. United States. doi:10.1063/1.2785874.
Liu, C., Xiao, X., Wang, J., Shi, B., Auciello, O., Carlisle, J. A., Carpick, R., Adiga, V., Univ. of Wisconsin at Madison, and Univ. of Pennsylvania. Mon . "Dielectric properties of hydrogen-incorporated chemical vapor deposited diamond thin films.". United States. doi:10.1063/1.2785874.
@article{osti_946676,
title = {Dielectric properties of hydrogen-incorporated chemical vapor deposited diamond thin films.},
author = {Liu, C. and Xiao, X. and Wang, J. and Shi, B. and Auciello, O. and Carlisle, J. A. and Carpick, R. and Adiga, V. and Univ. of Wisconsin at Madison and Univ. of Pennsylvania},
abstractNote = {Diamond thin films with a broad range of microstructures from a ultrananocrystalline diamond (UNCD) form developed at Argonne National Laboratory to a microcrystalline diamond (MCD) form have been grown with different hydrogen percentages in the Ar/CH{sub 4} gas mixture used in the microwave plasma enhanced chemical vapor deposition (CVD) process. The dielectric properties of the CVD diamond thin films have been studied using impedance and dc measurements on metal-diamond-metal test structures. Close correlations have been observed between the hydrogen content in the bulk of the diamond films, measured by elastic recoil detection (ERD), and their electrical conductivity and capacitance-frequency (C-f) behaviors. Addition of hydrogen gas in the Ar/CH{sub 4} gas mixture used to grow the diamond films appears to have two main effects depending on the film microstructure, namely, (a) in the UNCD films, hydrogen incorporates into the atomically abrupt grain boundaries satisfying sp{sup 2} carbon dangling bonds, resulting in increased resistivity, and (b) in MCD, atomic hydrogen produced in the plasma etches preferentially the graphitic phase codepositing with the diamond phase, resulting in the statistical survival and growth of large diamond grains and dominance of the diamond phase, and thus having significant impact on the dielectric properties of these films.},
doi = {10.1063/1.2785874},
journal = {J. Appl. Phys.},
number = 2007,
volume = 102,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • Highly (100) textured Pb(ScTa){sub 1{minus}x}Ti{sub x}O{sub 3} (x=0{endash}0.3) thin films were grown on LaNiO{sub 3}/Pt/Ti electrode-coated Si substrate using metal-organic chemical vapor deposition at 685thinsp{degree}C. Ti addition was introduced to modify the dielectric properties. Diffuse phase transition, typical of relaxor ferroelectrics was noticed. As Ti content increased from 0{percent} to 30{percent}, the phase transition temperature (T{sub max}) gradually shifted from {minus}10 to 120thinsp{degree}C with the dielectric constant at T{sub max} increased from 1397 to 1992 (1 kHz). Loss tangent values are generally below 0.025. {copyright} {ital 1999 American Institute of Physics.}
  • Etching of hot-filament, chemical vapor deposited, diamond thin films utilizing low energy ion irradiation was investigated. The films used in this study were boron doped polycrystalline diamond, deposited on [ital p]-type (100) oriented silicon substrates. A low voltage dc corona discharge with an oxygen plasma was used to sputter etch the films. Surfaces were investigated by scanning electron microscopy and profilometry. Etch rates were approximately 500 A/min, depending on the various processing conditions. Characteristics of In/diamond/Si Schottky diodes were used to evaluate the electrical properties of diamond surfaces with various treatments. Results indicate that plasma etching can significantly affect Schottkymore » device characteristic.« less
  • Temperature programmed desorption was used to measure the desorption kinetics of hydrogen and its isotopes from chemical vapor deposited diamond surfaces. The desorption spectra are surprisingly simple considering the polycrystalline nature of the sample, exhibiting a single peak at [similar to]1300 K for a heating rate of 6 K/s. There is no isotope effect to the desorption, and neither the position of the peak maximum nor the peak width change with increasing hydrogen coverage. The maximum surface coverage achieved is approximately one monolayer. The spectra can be represented by a single peak first order desorption model, yielding kinetic parameters ofmore » [ital E][sub [ital a]]=51 kcal/mol and [nu]=5[times]10[sup 7] s[sup [minus]1]. An alternate model of multiple desorption sites with a Gaussian-distributed population gives kinetic parameters of [ital E][sub [ital a],mean]=82 kcal/mol, [nu]=9[times]10[sup 12] s[sup [minus]1], and [sigma] (the width of the Gaussian distribution)=3 kcal/mol. A comparison to desorption from low-index natural diamond surfaces is presented.« less
  • Nitrogen-doped diamond-like carbon (DLC) or amorphous hydrogenated carbon (a-C:H) films were grown by plasma enhanced chemical vapor deposition using methane and nitrogen gases as precursors. The effects of nitrogen trifluoride (NF[sub 3]) on these nitrogen-doped DLC films were also investigated. The deposition rate decreases sharply with the addition of nitrogen in the absence of NF[sub 3] due to dilution, while it increases in the presence of NF[sub 3] due, presumably, to the reduction of activated hydrogen species by the fluorine radical (F[sup [minus]]). X-ray photoelectron spectra reveal a nitrogen concentration in the range of 9.3 to 13.8% in these DLCmore » films with a C 1s electron binding energy of 287-288 eV, indicating the diamond-like structure. Infrared spectra of DLC films indicate the presence of amino groups (N-H) and nitrile and/or isonitrile (C [triple bond] V N) groups giving strong evidence of sp carbon. Diamond like carbon films deposited in CH[sub 4] + N[sub 2] (with and without NF[sub 3]) have a lower refractive index, a lower bulk resistivity, and a lower optical bandgap than films deposited using CH[sub 4] due to a lower hydrogen content in the films. 19 refs., 12 figs., 3 tabs.« less
  • Results of room-temperature optical studies on {similar to}10 micron thick, free-standing diamond films are reported. The films were grown on Si(100) substrates by hot filament-assisted chemical vapor deposition (CVD) from a methane/hydrogen mixture. The as-grown, free surface of the films exhibited a surface roughness of scale {sigma}{similar to}0.2 to 5 microns, depending on the methane/hydrogen mixture, which introduces significant optical scattering loss for frequencies greater than 0.5 eV. Specular reflection and transmission spectra in the range 0.01--10 eV were collected. Below the threshold for interband adsorption near {similar to}5 eV, the films studied behaved approximately as thin parallel plates ofmore » refractive index 2.4, with the rough free surface leading to increasingly larger loss of specular transmission/reflection with decreasing wavelength. Structure in the mid-infrared transmission spectra was observed and attributed to disorder-induced one-phonon absorption, intrinsic multi-phonon absorption, and infrared active --C--H{sub 2} stretching modes. The strength of the C--H band was observed to increase with increasing methane pressure in the growth chamber. At 5.3 eV, the onset of interband absorption was observed, in good agreement with the value of the indirect bandgap in type IIa (intrinsic) diamond.« less