Fabrication and characterization of UV-LEDs

Show simple item record

dc.contributor.advisor Parbrook, Peter James en
dc.contributor.author Pampili, Pietro
dc.date.accessioned 2019-03-19T12:41:52Z
dc.date.issued 2019
dc.date.submitted 2019
dc.identifier.citation Pampili, P. 2019. Fabrication and characterization of UV-LEDs. PhD Thesis, University College Cork. en
dc.identifier.endpage 217 en
dc.identifier.uri http://hdl.handle.net/10468/7641
dc.description.abstract This thesis investigates the emerging technology of ultraviolet light-emitting diodes (UV LEDs) based on III-nitride materials. Despite the incredible improvement of these devices over the past decade, if compared with visible LEDs based on the same semiconductor system, UV LEDs still suffer from a much reduced efficiency that severely limits their potential. The technological issues responsible for this problem have been analysed and possible solutions and mitigation strategies have been proposed, both at growth and fabrication level. In particular, the n-type doping of the AlGaN materials used in the cladding layers of these devices has been optimized, for AlN concentrations in the range of 50–85%. The transport mechanism in these materials has also been studied, and the presence of a significant impurity conduction at room temperature has been detected; the consequences of this fact on the doping optimization have been highlighted. A deep-UV LED for space application emitting below 250 nm, and a near-UV LED emitting at 340 nm—in whose active region an InAlN alloy has been used in place of the more common AlGaN—have both been successfully demonstrated. The use of micron-sized emitters has been investigated with the aim of improving switching characteristics and light-extraction efficiency of these devices. An optical bandwidth of over 20 MHz has been demonstrated for the deep-UV LED, as required by the funding agency. Thanks to the optimization work performed on the reflective sidewalls of the micro-emitters, an increase of light-extraction efficiency up to four times was shown. en
dc.format.mimetype application/pdf en
dc.language.iso en en
dc.publisher University College Cork en
dc.rights © 2019, Pietro Pampili. en
dc.rights.uri http://creativecommons.org/licenses/by-nc-nd/3.0/ en
dc.subject UV LED en
dc.subject AlGaN en
dc.subject InAlN en
dc.subject Doping en
dc.subject Device fabrication en
dc.subject Micro-LED en
dc.title Fabrication and characterization of UV-LEDs en
dc.type Doctoral thesis en
dc.type.qualificationlevel Doctoral en
dc.type.qualificationname PhD en
dc.internal.availability Full text not available en
dc.check.info Restricted to everyone for one year en
dc.check.date 2020-03-18T12:41:52Z
dc.description.version Accepted Version
dc.description.status Not peer reviewed en
dc.internal.school Electrical and Electronic Engineering en
dc.check.reason This thesis contains data which has not yet been published en
dc.check.opt-out No en
dc.thesis.opt-out false
dc.check.entireThesis Entire Thesis Restricted
dc.check.embargoformat Apply the embargo to the e-thesis on CORA (If you have submitted an e-thesis and want to embargo it on CORA) en
ucc.workflow.supervisor peter.parbrook@tyndall.ie
dc.internal.conferring Spring 2019 en
dc.internal.ricu Tyndall National Institute en


Files in this item

Files Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record

© 2019, Pietro Pampili. Except where otherwise noted, this item's license is described as © 2019, Pietro Pampili.
This website uses cookies. By using this website, you consent to the use of cookies in accordance with the UCC Privacy and Cookies Statement. For more information about cookies and how you can disable them, visit our Privacy and Cookies statement