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

Title: Multiple delta doping of single crystal cubic boron nitride films heteroepitaxially grown on (001)diamonds

Abstract

Phase pure cubic boron nitride (c-BN) films have been epitaxially grown on (001) diamond substrates at 900 °C. The n-type doping of c-BN epitaxial films relies on the sequential growth of nominally undoped (p-) and Si doped (n-) layers with well-controlled thickness (down to several nanometer range) in the concept of multiple delta doping. The existence of nominally undoped c-BN overgrowth separates the Si doped layers, preventing Si dopant segregation that was observed for continuously doped epitaxial c-BN films. This strategy allows doping of c-BN films can be scaled up to multiple numbers of doped layers through atomic level control of the interface in the future electronic devices. Enhanced electronic transport properties with higher hall mobility (10{sup 2} cm{sup 2}/V s) have been demonstrated at room temperature as compared to the normally continuously Si doped c-BN films.

Authors:
 [1];  [2]
  1. State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China)
  2. Institute of Solid State Physics, Ulm University, D-89069 Ulm (Germany)
Publication Date:
OSTI Identifier:
22303395
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 25; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BORON NITRIDES; CARRIER MOBILITY; CRYSTAL GROWTH; CUBIC LATTICES; DIAMONDS; DOPED MATERIALS; ELECTRONIC EQUIPMENT; EPITAXY; FILMS; INTERFACES; LAYERS; MONOCRYSTALS; SEGREGATION; SILICON ADDITIONS; SUBSTRATES; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 1000-4000 K; THICKNESS

Citation Formats

Yin, H., E-mail: hyin@jlu.edu.cn, and Ziemann, P. Multiple delta doping of single crystal cubic boron nitride films heteroepitaxially grown on (001)diamonds. United States: N. p., 2014. Web. doi:10.1063/1.4885835.
Yin, H., E-mail: hyin@jlu.edu.cn, & Ziemann, P. Multiple delta doping of single crystal cubic boron nitride films heteroepitaxially grown on (001)diamonds. United States. doi:10.1063/1.4885835.
Yin, H., E-mail: hyin@jlu.edu.cn, and Ziemann, P. 2014. "Multiple delta doping of single crystal cubic boron nitride films heteroepitaxially grown on (001)diamonds". United States. doi:10.1063/1.4885835.
@article{osti_22303395,
title = {Multiple delta doping of single crystal cubic boron nitride films heteroepitaxially grown on (001)diamonds},
author = {Yin, H., E-mail: hyin@jlu.edu.cn and Ziemann, P.},
abstractNote = {Phase pure cubic boron nitride (c-BN) films have been epitaxially grown on (001) diamond substrates at 900 °C. The n-type doping of c-BN epitaxial films relies on the sequential growth of nominally undoped (p-) and Si doped (n-) layers with well-controlled thickness (down to several nanometer range) in the concept of multiple delta doping. The existence of nominally undoped c-BN overgrowth separates the Si doped layers, preventing Si dopant segregation that was observed for continuously doped epitaxial c-BN films. This strategy allows doping of c-BN films can be scaled up to multiple numbers of doped layers through atomic level control of the interface in the future electronic devices. Enhanced electronic transport properties with higher hall mobility (10{sup 2} cm{sup 2}/V s) have been demonstrated at room temperature as compared to the normally continuously Si doped c-BN films.},
doi = {10.1063/1.4885835},
journal = {Applied Physics Letters},
number = 25,
volume = 104,
place = {United States},
year = 2014,
month = 6
}
  • We investigated the formation of cubic boron nitride (c-BN) thin films on diamond (001) and (111) substrates by ion-beam-assisted molecular beam epitaxy (MBE). The metastable c-BN (sp{sup 3}-bonded BN) phase can be epitaxially grown as a result of the interplay between competitive phase formation and selective etching. We show that a proper adjustment of acceleration voltage for N{sub 2}{sup +} and Ar{sup +} ions is a key to selectively discriminate non-sp{sup 3} BN phases. At low acceleration voltage values, the sp{sup 2}-bonded BN is dominantly formed, while at high acceleration voltages, etching dominates irrespective of the bonding characteristics of BN.
  • We present high-resolution transmission electron-microscopic observations of the [ital sp][sup 2]-bonded material that remains with the [ital sp][sup 3]-bonded cubic boron nitride (cBN) in films grown by ion-assisted deposition. These observations show regions of [ital sp][sup 2]-bonded material that are in a three-layer stacking configuration rather than the two-layer configuration of hexagonal boron nitride. Measurement of the lattice fringe angles shows that the observed three-layer stacking is consistent with the metastable, rhombohedral structure (rBN). Significantly, rBN allows for a diffusionless pathway for cBN synthesis under high pressure, unlike the high-activation-energy route that is required to directly convert the hexagonal phasemore » to cBN. This low-energy pathway is considered in relation to recent work in the literature indicating that ion-induced compressive stress plays a critical role in the synthesis of thin-film cBN.« less
  • A microstructural study of boron nitride films grown by ion-assisted pulsed laser deposition is presented. Fourier transform infrared spectroscopy, electron-energy-loss spectroscopy, and electron-diffraction measurements indicate that within the ion-irradiated region on the substrate, the film consists of a high fraction of the cubic phase ([ital c]BN) with a small amount of the turbostratic phase; outside the irradiated region, only the turbostratic phase is detected. Conventional and high-resolution electron microscopic observations show that the [ital c]BN is in the form of twinned crystallites, up to 40 nm in diameter. Particulates, formed by the laser ablation process, reduce the yield of [italmore » c]BN in the irradiated regions by shadowing local areas from the ion beam. The films exhibit a layered structure with an approximately 30-nm-thick layer of oriented turbostratic material forming initially at the silicon substrate followed by the [ital c]BN. The observations of oriented turbostratic material and twinned [ital c]BN crystallites are discussed in relation to a previously proposed compressive stress-induced mechanism for [ital c]BN synthesis by ion-assisted film deposition.« less
  • Relaxation of the intrinsic stress of cubic boron nitride (cBN) thin films has been studied by x-ray diffraction (XRD) using synchrotron light. The stress relaxation has been attained by simultaneous medium-energy ion bombardment (2-10 keV) during magnetron sputter deposition, and was confirmed macroscopically by substrate curvature measurements. In order to investigate the stress-release mechanisms, XRD measurements were performed in in-plane and out-of-plane geometry. The analysis shows a pronounced biaxial state of compressive stress in the cBN films grown without medium-energy ion bombardment. This stress is partially released during the medium-energy ion bombardment. It is suggested that the main path formore » stress relaxation is the elimination of strain within the cBN grains due to annealing of interstitials.« less
  • The surface symmetry of cubic boron nitride (111) (c-BN) is characterized by low-electron energy diffraction. The polished c-BN (111) and hydrogen-plasma-treated sample both exhibit a 1{times}1 surface structure. The surface is effectively etched by hydrogen plasma. High-resolution Auger and electron-energy-loss spectroscopy studies confirmed that the hydrogen-etched surface retains the integrity of crystalline c-BN (111). Characteristic energy-loss peaks at 15 eV due to an interband transition and at 37 eV due to a bulk plasmon can be observed on the single-crystal surface, even though they are usually absent from the energy-loss spectra of pyrolytic or polycrystalline BN samples. {copyright} {ital 1997}more » {ital The American Physical Society}« less