Photodetectors based on colloidal quantum dots

Inspired by recent work demonstrating photocurrent enhancement in quantum-dot (QD) solids via post-deposition chemical annealing and by recent successes incorporating single monolayers of QDs in light-emitting devices (QD-LEDs), we set out to develop thin-film, layered photodetectors in which the active layer is a chemically annealed QD solid. This thesis reports initial steps in this development. Chapters 1 and 2 contain introductory material. In Chapter 3, we demonstrate a layered QD photodetector (QD-PD) in which the active layer is a 200-nm thick film of CdSe QDs annealed with n-butylamine. These "thick-slab" devices, active in the visible spectrum, represent a minimal transformation from the transverse channel test structures employed for more fundamental studies to a layered, sandwich geometry. The thick-slab design exhibits a number of desirable characteristics, including near-unity internal quantum efficiency and a 50-kHz bandwidth. More complex QD-PD designs, allowing the successful incorporation of much thinner QD solids, are discussed in Chapter 4, and these devices provide insight into the zero-bias operation of thick-slab QD-PDs.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Oertel, David C. (David Charles)

Advisor dc:contributor.advisor

• Moungi G. Bawendi.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39737

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39737