Atomic structure of steps and defects on the clean diamond (100)-2×1 surface studied using ultrahigh vacuum scanning tunneling microscopy

Stallcup, Richard E.; Pérez, Jose

doi:10.1063/1.1527697

Cited by 11 publications

(8 citation statements)

References 8 publications

(7 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is in contrast to the more uniform view of the dimer rows seen in the STM images on hydrogen-free CVD semiconducting diamond 21 or single-crystal insulating diamond. 20 In the latter STM study, a uniform one-dimensional density of states was observed due to the delocalization of the barrier resonances along the dimer rows.…”

contrasting

confidence: 49%

“…This is in contrast to high-resolution STM images of the hydrogenated diamond 6,15-18 and hydrogen-free diamond surfaces. [19][20][21] STM images of the hydrogenated diamond ͑100͒ surface could not separate the hydrogen atoms, which are clearly resolved in the NC-AFM image presented here. On the clean diamond ͑100͒ surface, individual C-C dimers could not be seen with the STM whereas they are clearly visible with the NC-AFM as demonstrated in this work.…”

mentioning

confidence: 71%

See 1 more Smart Citation

Atomic-resolution imaging of clean and hydrogen-terminated C(100)-(2×1)diamond surfaces using noncontact AFM

et al. 2010

View full text Add to dashboard Cite

High-purity, type IIa diamond is investigated by noncontact atomic force microscopy ͑NC-AFM͒. We present atomic-resolution images of both the electrically conducting hydrogen-terminated C͑100͒-͑2 ϫ 1͒ :H surface and the insulating C͑100͒-͑2 ϫ 1͒ surface. For the hydrogen-terminated surface, a nearly square unit cell is imaged. In contrast to previous scanning tunneling microscopy experiments, NC-AFM imaging allows both hydrogen atoms within the unit cell to be resolved individually, indicating a symmetric dimer alignment. Upon removing the surface hydrogen, the diamond sample becomes insulating. We present atomic-resolution images, revealing individual C-C dimers. Our results provide real-space experimental evidence for a ͑2 ϫ 1͒ dimer reconstruction of the truly insulating C͑100͒ surface. Hydrogenated and clean diamond surfaces ͓see model in Figs. 1͑a͒ and 1͑b͔͒ have attracted considerable interest in recent years, motivated by the unique electronic, thermal, mechanical, and optical properties of diamond, 1-3 which makes it suitable for high power laser and gyrotron applications or field-effect transistors. 4 Most of the diamond samples, both natural diamond and artificial chemical-vapor deposition ͑CVD͒ diamond, have a low impurity concentration and are insulating. For example, so-called type IIa diamond exhibits an impurity concentration of less than 1 ppm. Therefore, type IIa diamond is not sufficiently conducting for scanning tunneling microscopy ͑STM͒ imaging unless a water layer is present. 5,6 Thus, atomic force microscopy ͑AFM͒ appears to be the ideal tool for a high-resolution study of the diamond surface. Highest resolution has recently been demonstrated for bare dielectric surfaces 7-9 and molecules on insulators, 10-13 including submolecular resolution of a pentacene molecule at low temperature. 14 However, despite many attempts, atomic-scale AFM imaging of diamond surfaces has not been successful so far. To progress further in our understanding of diamond, a detailed characterization of its surface structure is necessary.In this Rapid Communication, we present atomically resolved noncontact AFM ͑NC-AFM͒ images that reveal the individual hydrogen atoms on the hydrogenated diamond ͑100͒ surface, and the C-C dimers on the hydrogen-free diamond ͑100͒ surface. This is in contrast to high-resolution STM images of the hydrogenated diamond 6,15-18 and hydrogen-free diamond surfaces.19-21 STM images of the hydrogenated diamond ͑100͒ surface could not separate the hydrogen atoms, which are clearly resolved in the NC-AFM image presented here. On the clean diamond ͑100͒ surface, individual C-C dimers could not be seen with the STM whereas they are clearly visible with the NC-AFM as demonstrated in this work. As a matter of fact, NC-AFM offers greatly enhanced resolution compared to STM for both the hydrogenated and clean diamond surfaces.

show abstract

contrasting

confidence: 49%

mentioning

confidence: 71%

Atomic-resolution imaging of clean and hydrogen-terminated C(100)-(2×1)diamond surfaces using noncontact AFM

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Both filled- (2 eV below fermi) and empty-state (2 eV above fermi) images were simulated for bare and adsorbed diamond(001) by nitrogen species and are visualized in Figure . At present, there is limited STM work on diamond − yielding images of bare diamond (001) similar to Figure a′,a″. In the filled-state images (Figure , middle column), the carbon dimer rows of the diamond substrate are bright, as dominated by the π bonding state (Figure a′); the nitrogen species are visible because there are N states (Figure b′–d′) in the sampled energy window.…”

Section: Resultsmentioning

confidence: 99%

Atomistic Insight into Nitrogen-Terminated Diamond(001) Surfaces by the Adsorption of N, NH, and NH₂: A Density Functional Theory Study

2021

View full text Add to dashboard Cite

Layer-by-layer construction of diamond devices for spin-sensing calls for the atomistic understanding of the nitrogen species on diamond surfaces. Motivated by recent experiments, we used density functional theory simulations to examine the adsorption of nitrogen species (N, NH, and NH2) on bare and hydrogenated diamond(001) surfaces. On the bare substrate, we find that nitrogen species favor to attack the CC dimers at low coverages, forming N(ad) and NH(ad) in a bridge configuration and NH2(ad) in a terminal configuration. At increasing coverages up to one full monolayer, the computed adsorption geometries and energetics suggest that the adsorbate–adsorbate interactions are attractive for N(ad), but repulsive for NH(ad) and NH2(ad). On the hydrogenated substrate, the adsorbed nitrogen species are subject to structural modification, as resulted from the weakened adsorbate–substrate interactions. Further, we calculated the vibration of nitrogen species and the 1s core-level shift of surface carbons, providing atomistic insights into the nature of surface bonding. Lastly, we simulated images of representative nitrogen species adsorbed on diamond(001), guiding future work using scanning tunneling microscopy.

show abstract

“…Atomically smooth C(100) surfaces can be prepared through the growth of homoepitaxial layers by chemical vapor deposition 51,52 . Upon thermal annealing, hydrogen desorption takes place and leads to the formation of clean C(100) 2 × 1 surfaces via surface reconstruction [53][54][55][56] . Figure 8 shows the variation of total energy during the process of wafer bonding between two clean C(100) 2 × 1 surfaces.…”

Section: Resultsmentioning

confidence: 99%

Direct band gap carbon superlattices with efficient optical transition

Kim

Lee

et al. 2016

Phys. Rev. B

View full text Add to dashboard Cite

We report pure carbon-based superlattices that exhibit direct band gaps and excellent optical absorption and emission properties at the threshold energy. The structures are nearly identical to that of cubic diamond except that defective layers characterized by five- and seven-membered rings are intercalated in the diamond lattice. The direct band gaps lie in the range of 5.6~5.9 eV, corresponding to wavelengths of 210~221 nm. The dipole matrix elements of direct optical transition are comparable to that of GaN, suggesting that the superlattices are promising materials as an efficient deep ultraviolet light emitter. Molecular dynamics simulations show that the superlattices are thermally stable even at a high temperature of 2000 K. We provide a possible route to the synthesis of superlattices through wafer bonding of diamond (100) surfaces.Comment: 9 pages, 11 figure

show abstract

Atomic structure of steps and defects on the clean diamond (100)-2×1 surface studied using ultrahigh vacuum scanning tunneling microscopy

Cited by 11 publications

References 8 publications

Atomic-resolution imaging of clean and hydrogen-terminated C(100)-(2×1)diamond surfaces using noncontact AFM

Atomic-resolution imaging of clean and hydrogen-terminated C(100)-(2×1)diamond surfaces using noncontact AFM

Atomistic Insight into Nitrogen-Terminated Diamond(001) Surfaces by the Adsorption of N, NH, and NH₂: A Density Functional Theory Study

Direct band gap carbon superlattices with efficient optical transition

Contact Info

Product

Resources

About

Atomic structure of steps and defects on the clean diamond (100)-2×1 surface studied using ultrahigh vacuum scanning tunneling microscopy

Cited by 11 publications

References 8 publications

Atomic-resolution imaging of clean and hydrogen-terminated C(100)-(2×1)diamond surfaces using noncontact AFM

Atomic-resolution imaging of clean and hydrogen-terminated C(100)-(2×1)diamond surfaces using noncontact AFM

Atomistic Insight into Nitrogen-Terminated Diamond(001) Surfaces by the Adsorption of N, NH, and NH2: A Density Functional Theory Study

Direct band gap carbon superlattices with efficient optical transition

Contact Info

Product

Resources

About

Atomistic Insight into Nitrogen-Terminated Diamond(001) Surfaces by the Adsorption of N, NH, and NH₂: A Density Functional Theory Study