Project

Back to overview

Electronic Impurity Doping of Semiconductor Nanocrystals II

English title Electronic Impurity Doping of Semiconductor Nanocrystals II
Applicant Norris David J.
Number 159228
Funding scheme Project funding (Div. I-III)
Research institution Professur für Material-Engineering ETH Zürich
Institution of higher education ETH Zurich - ETHZ
Main discipline Material Sciences
Start/End 01.05.2015 - 30.04.2016
Approved amount 59'046.00
Show all

All Disciplines (2)

Discipline
Material Sciences
Physical Chemistry

Keywords (10)

semiconductor nanocrystals; quantum dots; fluorescence; acceptors; optical materials; thin-film transistors; donors; doping; nanomaterials; density functional theory

Lay Summary (German)

Lead
Halbleiter Nanopartikel - auch Nanokristalle genannt - können aufgrund ihrer kleinen Grösse einzigartige und potentiell nützliche Eigenschaften haben. Dieses Projekt untersucht den Einbau von Fremdatomen in Nanokristallen. Fremdatome spielen schon in herkömmlichen Halbleiterbauelementen eine zentrale Rolle. Bei Nanokristallen können sie noch dramatischere Auswirkungen haben. Hinzu kommt, dass Fremdatome die Lösung zu etlichen Schlüsselproblemen in Anwendungen von Nanokristallen sein können.
Lay summary

Ein Doktorand wird das Dotieren von Halbleiter-Nanokristallen mittels elektronisch aktiver Fremdatome untersuchen. Das Projekt wird theoretische Modelle aufgrund detaillierter Berechnungen erstellen. Zusätzlich zur Schulung und Weiterbildung des Doktorand ist das erwartete Ergebnis des Projektes ein vertieftes Verständnis der fundamentalen Eigenschaften von dotierten Nanokristallen sowie deren Effekte auf Nanokristall-basierte Bauelemente und Anwendungen. Erste Experimente zeigten schon interessantes und unerwartetes Verhalten und weitere Überraschungen werden erwartet.

Direct link to Lay Summary Last update: 14.01.2015

Lay Summary (English)

Lead
Nanometer-scale semiconductor particles, known as nanocrystals, can have unique and potentially useful properties due to their small size. This project will study the addition of impurities (or dopants) into these nanocrystals. Dopants already play a critical role in conventional semiconductor devices. Impurities in nanocrystals can exhibit even more dramatic behavior. Further, doping can help address several key problems in potential applications of nanocrystals.
Lay summary

The project supports the final year of a Ph.D. student to investigate the addition of electronically active impurities in semiconductor nanocrystals.  The student will continue to generate theoretical models from detailed calculations. In addition to completing the training of the Ph.D. student, the expected outcome of the project is an understanding of the fundamental properties of doped nanocrystals and how they can impact nanocrystal devices and applications. Early experiments have already shown interesting and unexpected behavior, and further surprises are expected. 

Direct link to Lay Summary Last update: 14.01.2015

Responsible applicant and co-applicants

Employees

Publications

Publication
Ripening of Semiconductor Nanoplatelets
Ott Florian D., Riedinger Andreas, Ochsenbein David R., Knüsel Philippe N., Erwin Steven C., Mazzotti Marco, Norris David J. (2017), Ripening of Semiconductor Nanoplatelets, in Nano Letters, 17(11), 6870-6877.
An intrinsic growth instability in isotropic materials leads to quasi-two-dimensional nanoplatelets
Riedinger Andreas, Ott Florian D., Mule Aniket, Mazzotti Sergio, Knüsel Philippe N., Kress Stephan J. P., Prins Ferry, Erwin Steven C., Norris David J. (2017), An intrinsic growth instability in isotropic materials leads to quasi-two-dimensional nanoplatelets, in Nature Materials, 16, 743-748.

Collaboration

Group / person Country
Types of collaboration
Naval Research Laboratory (NRL) United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Exchange of personnel

Awards

Title Year
EMRS Best Oral Presentation in Symposium 2016

Associated projects

Number Title Start Funding scheme
188593 Towards Monodisperse Colloidal Semiconductor Nanocrystals 01.11.2019 Project funding (Div. I-III)
140617 Electronic Impurity Doping of Semiconductor Nanocrystals 01.05.2012 Project funding (Div. I-III)

Abstract

The aim of this proposal is to fund an extension/supplement for project 200021_140617 to support the final year of the Ph.D. student, Mr. Florian Ott. Mr. Ott began his doctoral studies at ETH Zurich on the same date as the original project (01.05.2012). Thus, he will have completed 3 years of his thesis when the current project ends (30.04.3015). We expect that Mr. Ott will require an additional year of funding to complete his doctoral work.During this final year, Mr. Ott will continue to perform theoretical studies on nanometer-scale semiconductor particles, or nanocrystals, in which electronically active impurity atoms (or dopants) have been incorporated. Even without such dopants, semiconductor nanocrystals, also known as colloidal quantum dots, can exhibit unique and potentially useful properties due to their small size. The addition of impurities to such particles is of interest for three reasons. First, the critical role that dopants play in semiconductor devices, such as the transistor, provides a strong motivation to study doped semiconductor nanocrystals. Second, impurities in nanocrystals should exhibit even more dramatic behavior than in bulk semiconductors because the dopants are confined in extremely small volumes. Finally, doping can help address key problems in potential applications of nanocrystals (e.g., light-emitting diodes and solar cells). In particular, many applications utilize thin films of densely-packed nanocrystals, and electronically active impurities can provide extra electrical carriers, i.e. electrons or holes, to the particles that enhance the conductivity of these films.After several decades of effort, a few groups (including the applicant’s) have demonstrated the first examples of colloidal nanocrystals with electronically active impurities. During the first 2.5 years of this project, Mr. Ott has made tremendous progress in using density functional theory (DFT) to explain several experimental puzzles reported for these materials. Moreover, his results have provided fundamental understanding for a commonly used procedure to obtain new nanocrystal materials, cation exchange. To date, he has reported results for a prototypical system: Ag dopants in spherical CdSe nanocrystals (Phys. Rev. Lett., in press). In the remainder of his doctoral work, he will exploit his microscopic model to understand other common dopants, such as Cu, and in other nanocrystal shapes, such as nanoplatelets. Mr. Ott’s work is contributing greatly to ongoing experimental work on these systems in the applicant’s laboratory (funded through his chair).
-