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Study on the optoelectronic characteristics of nano quantum dot

The purpose of this thesis is to study the InAs self-organized quantum dots and InAs/GaAsN digital alloys. We have studied the optical properties of these structures after rapid thermal annealing. The measured samples are InGaAs/InAs¡BInGaAs/InAlAs/InAs¡BInGaAs/AlAs/InAs quantum dots and InAs/GaAsN short-period superlattice quantum well structures. We have investigated the effect of different strain-reducing layer (SRL) on the photoluminescence (PL) of self-assembled InAs/GaAs quantum dots. From experiments, the coverage layers of Al composition can increase the energy splitting between the ground and first excited states of the quantum dots. It is related to the thickness and composition of the cap layers. Using thick InAlAs and InGaAs together as a SRL results in the energy splitting up to 123meV. However the PL intensity decreases three times. After rapid thermal annealing up to 800¢XC, the QDs with Al-composed cap layer show no shift of peak wavelength.
For InAs/GaAsN digital alloys, through temperature dependent PL spectrum, we can observe PL peak has a blue shift form room temperature to 100K, and a red shift from 100K to 10K. It is similar to the InGaAsN quantum well. However, one of the samples shows temperature insensitive for the PL peaks.

Identiferoai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0722105-154551
Date22 July 2005
CreatorsChuang, Kuei-Ya
ContributorsTao-Yuan Chang, Hao-Chung Kuo, Tsong-Sheng Lay, Shoou-Jinn Chang, Ming-Hua Mao
PublisherNSYSU
Source SetsNSYSU Electronic Thesis and Dissertation Archive
LanguageCholon
Detected LanguageEnglish
Typetext
Formatapplication/pdf
Sourcehttp://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0722105-154551
Rightsnot_available, Copyright information available at source archive

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