NiGe on Ge(001) by reactive deposition epitaxy: An <i>in situ</i> ultrahigh-vacuum transmission-electron microscopy study

Nath, R.; Soo, Choong; Boothroyd, Chris; Yeadon, M.; Z., D.; Sun, Haiping; Chen, Y. B.; Pan, Xiaoqing; Foo, Y. L.

doi:10.1063/1.1929100

Cited by 16 publications

(7 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[8][9][10][11] This can be achieved by the implementation of a nickel-germanide contacting scheme, offering the advantage of self-alignment and low thermal budget. [12][13][14][15] In the past, it has been shown that the 1 / f noise of silicon p-n junctions is sensitive to the substrate type, i.e., the crystal growth technique, orientation, and the processing. [16][17][18] It was also demonstrated that cobalt silicidation can have a strong impact on the current noise spectral density S I in the forward operation.…”

mentioning

confidence: 99%

On the origin of the 1∕f noise in shallow germanium p+-n junctions

Todi

Sonde

Simoen

et al. 2007

Applied Physics Letters

View full text Add to dashboard Cite

The low-frequency noise of shallow germanium p +-n junctions is studied, for diodes with or without a nickel-germanide Ohmic contact. It is shown that the application of NiGe not only reduces the series resistance, resulting in a higher forward current, but also results in a lower 1 / f noise at forward bias. From the observed geometry dependence, it is concluded that germanidation suppresses the 1 / f noise generated in the series resistance, leaving surface-state-assisted generation-recombination at the junction perimeter as the dominant flicker noise source.

show abstract

mentioning

confidence: 99%

On the origin of the 1∕f noise in shallow germanium p+-n junctions

Todi

Sonde

Simoen

et al. 2007

Applied Physics Letters

View full text Add to dashboard Cite

show abstract

“…This has recently triggered research on NiGe formation and the corresponding electrical characteristics. [1][2][3][4][5][6][7][8][9][10][11] Besides the fabrication of low-resistive ohmic contacts, Ni-or Ptgermanides can also be employed as Schottky barrier source-drain contacts. [12][13][14][15] In the past, some studies have been devoted to the phase formation in the Ni-Ge, [16][17][18][19][20] Pd-Ge, 17,18,[21][22][23][24][25] and Pt-Ge ͑Ref.…”

mentioning

confidence: 99%

Point-Defect Generation in Ni-, Pd-, and Pt-Germanide Schottky Barriers on n-Type Germanium

Simoen

Opsomer

Claeys

et al. 2007

J. Electrochem. Soc.

View full text Add to dashboard Cite

In this paper, the creation of point defects in n-type germanium by Ni-, Pd-, or Pt-germanidation is investigated by means of deep-level transient spectroscopy. The Pt-and Pd-germanidation is achieved by a ramped annealing step up to 300 and 500°C of a 30 nm Ar-ion sputtered metal layer. Contrasting behavior is found between Ni, and Pd and Pt; indiffusion of nickel is found starting from 400°C, while in the second case, vacancy-related deep levels have been observed at lower rapid thermal annealing temperatures. Evidence is provided that these defects are most likely formed during the sputtering of the heavy metal atoms, introducing radiation damage in the Ge substrate. Finally, the impact of these deep levels on the current-voltage characteristics of the obtained metal-germanide Schottky barriers is discussed.The high carrier mobility in germanium has brought this semiconductor material recently back on the microelectronics scene. However, there are many hurdles to overcome before Ge complementary metal-oxide semiconductor ͑CMOS͒ can be regarded as a full competitor for the well-established silicon technology. One of the major handicaps is the lack of basic materials' science in comparison with silicon. Critical issues for the moment are the passivation of the germanium-dielectric interface and the control/reduction of the junction leakage current. Another factor receiving quite some interest now is source-drain junction metallization. Similar to the case of silicon, the use of germanidation offers a number of advantages, whereby self-alignment and a low sheet resistance are among the more important ones. This has recently triggered research on NiGe formation and the corresponding electrical characteristics. [1][2][3][4][5][6][7][8][9][10][11] Besides the fabrication of low-resistive ohmic contacts, Ni-or Ptgermanides can also be employed as Schottky barrier source-drain contacts. [12][13][14][15] In the past, some studies have been devoted to the phase formation in the Ni-Ge, [16][17][18][19][20]17,18,[21][22][23][24][25] and Pt-Ge ͑Ref. 26 and 27͒ system. It was, for example, demonstrated that the first phase expected to be formed is Ni 2 Ge and PdGe. 17 In a recent systematic study of transition metal germanides, it was shown by in situ X-ray diffraction ͑XRD͒ that NiGe and PdGe offer the lowest sheet resistance and remain stable over the widest temperature range during ramp anneals, 28 so they are good candidates for contact metallization in Ge MOS devices.One practical concern in the germanidation process is whether it introduces point defects in the semiconductor material, because this can affect the leakage current of the source-drain junctions. Depending on the diffusing species, one can expect that either metals or vacancies are injected ͑diffusing͒ in the Ge substrate, which is also crucial information to understand the germanidation itself.In this work, point-defect generation is studied for a number of technologically relevant germanides belonging to the same column of the periodic table of elements ...

show abstract

“…A JEOL JEM 2000V in situ UHV-TEM (base pressure of 1 Â 10 À 9 Torr) equipped with an electron beam evaporator (Fe rod, 99.95%), sample heating capability (room temperature to 1200 1C), a Gatan Image Filter (GIF2000), and a Gatan Dual-Vision (DV300) digital camera [26] enabled both static and dynamic recording of growth. The substrates are 2.5 Â 2.5 mm 2 Ge(001) slabs that were mechanically polished, dimpled, and thinned by Ar þ ion bombardment from the backside to obtain an electron transparent thin area.…”

Section: Methodsmentioning

confidence: 99%