1 / 8

Nanowire Doping via Monolayer Doping

Nanowire Doping via Monolayer Doping. Patrick Bennett, AS&T. Ho, et. al. Nature Materials 7 , 62-67 (2008). Motivation. Ions have sufficient energy to pass through a nanowire without stopping, yet still causing serious lattice damage.

teleri
Télécharger la présentation

Nanowire Doping via Monolayer Doping

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nanowire Doping via Monolayer Doping Patrick Bennett, AS&T Ho, et. al. Nature Materials7, 62-67 (2008)

  2. Motivation • Ions have sufficient energy to pass through a nanowire without stopping, yet still causing serious lattice damage. • Spin on techniques lack control and uniformity at the nanoscale. Ho, et. al. Nature Materials7, 62-67 (2008)

  3. Process Outline • Process carried out in glove box in N2 environment Ho, et. al. Nature Materials7, 62-67 (2008)

  4. Results X-Ray Photoelectron Spectrometry (24 Hrs elapsed) • Low amount of post deposition oxidation (inset unreacted substrate) • Dopant profile similar to conventional techniques (limited source) • Observed self limiting surface reaction for both P (Diethyl 1-propylphosphonate) and B (allyboronic acid pinacol ester) dopants Si-C bond Si-O bond Ambient exposure Ho, et. al. Nature Materials7, 62-67 (2008)

  5. Results, continued • 33% efficiency of Boron doping (deduced from theoretical coverage and sheet resistance). Cut in half without capping. • 95% efficiency for Phosphorus. Due to decreased diffusivity of P in SiO2 • RS std. dev. across sample: 2-5% • High reproducibility B P Ho, et. al. Nature Materials7, 62-67 (2008)

  6. Dose Modulation Reduction of Binding sites for precursor • Mixed solution of blank (dodecene) and dopant (B) precursors • Equivalent five and twentyfold decrease in dose suggests similar surface reactivity Tunability of doping via precursor structure • Footprint of precursor molecule governs surface concentration • 6x reduction in dose using trioctylphosphine oxide (TOP) over DPP 6x footprint Ho, et. al. Nature Materials7, 62-67 (2008)

  7. Nanowires • Proof of concept: 2 terminal device (back gated) • Ohmic contacts formed with DPP • n-type switching obtained with TOP(400x enlargement??) • ION/IOFFratio of 103 • 1D doping profile not modeled. • Applied with more success to ultrathin SOI substrates (data not shown) Ho, et. al. Nature Materials7, 62-67 (2008)

  8. Summary • Novel doping technique • Highly controllable in bulk • Proof of concept, successfully doped nanowires • Carried out in restrictive environment, but not in vacuum (except for capping in e-beam evaporator) • Very shallow junction depth • Poor control over nanowire doping (expect more papers soon I’d assume) Comments Ho, et. al. Nature Materials7, 62-67 (2008)

More Related