III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes

Simple item page
dc.contributor.advisorFletcher, Jack C Qen_ZA
dc.contributor.authorThavar, Rajanen_ZA
dc.date.accessioned2016-08-24T12:55:18Z
dc.date.available2016-08-24T12:55:18Z
dc.date.issued1994en_ZA
dc.descriptionBibliography: pages 125-131.en_ZA
dc.description.abstractAlGaAs-GaAs graded index single confinement heterostructure single quantum well (GRIN-SCH SQW) lasers and both 35 GHz and 94 GHz Gunn diodes have been satisfactorily grown by organometallic vapour phase epitaxy (OMVPE). This work is based on the material development of such device structures and systematically shows the steps taken to achieve the final goal of repeatedly producing high quality devices geared towards small-scale production. The key elements of the process are the realisation of high quality AlGaAs compositionally graded layers, abrupt GaAs-AlGaAs as well as dopant heterointerfaces and silicon-dopant spikes. A consistently high quality of epitaxial GaAs and AlGaAs is achievable with controllable silicon, tellurium and zinc doping on both material systems. The OMVPE system is sufficiently calibrated to grow sharp transitions in GaAs doping interfaces and quantum wells in the order of 2.5 nm. SIMS measurements showed almost square doping profiles in the 35 GHz Gunn diode structure and was able to resolve a 5 nm Si-spike doping layer in GaAs. The SIMS results of the 94 GHz Gunn diode material clearly indicates the presence of all layers with certain measured values evolving exactly as designed. These achievements are attributed to the fine pressure and flow control implemented on the reactor system by using automated steps to control the growth process.en_ZA
dc.identifier.apacitationThavar, R. (1994). <i>III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes</i>. (Thesis). University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Chemical Engineering. Retrieved from http://hdl.handle.net/11427/21501en_ZA
dc.identifier.chicagocitationThavar, Rajan. <i>"III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes."</i> Thesis., University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Chemical Engineering, 1994. http://hdl.handle.net/11427/21501en_ZA
dc.identifier.citationThavar, R. 1994. III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Thavar, Rajan AB - AlGaAs-GaAs graded index single confinement heterostructure single quantum well (GRIN-SCH SQW) lasers and both 35 GHz and 94 GHz Gunn diodes have been satisfactorily grown by organometallic vapour phase epitaxy (OMVPE). This work is based on the material development of such device structures and systematically shows the steps taken to achieve the final goal of repeatedly producing high quality devices geared towards small-scale production. The key elements of the process are the realisation of high quality AlGaAs compositionally graded layers, abrupt GaAs-AlGaAs as well as dopant heterointerfaces and silicon-dopant spikes. A consistently high quality of epitaxial GaAs and AlGaAs is achievable with controllable silicon, tellurium and zinc doping on both material systems. The OMVPE system is sufficiently calibrated to grow sharp transitions in GaAs doping interfaces and quantum wells in the order of 2.5 nm. SIMS measurements showed almost square doping profiles in the 35 GHz Gunn diode structure and was able to resolve a 5 nm Si-spike doping layer in GaAs. The SIMS results of the 94 GHz Gunn diode material clearly indicates the presence of all layers with certain measured values evolving exactly as designed. These achievements are attributed to the fine pressure and flow control implemented on the reactor system by using automated steps to control the growth process. DA - 1994 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1994 T1 - III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes TI - III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes UR - http://hdl.handle.net/11427/21501 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/21501
dc.identifier.vancouvercitationThavar R. III-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodes. [Thesis]. University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Chemical Engineering, 1994 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/21501en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDepartment of Chemical Engineeringen_ZA
dc.publisher.facultyFaculty of Engineering and the Built Environment
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherChemical Engineeringen_ZA
dc.titleIII-V OMVPE growth and characterisation of graded AlₓGaₓ₋₁As-GaAs layers and heterointerfaces for the development of GRIN-SCH lasers and Gunn diodesen_ZA
dc.typeMaster Thesis
dc.type.qualificationlevelMasters
dc.type.qualificationnameMSc (Eng)en_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
thesis_ebe_1994_thavar_rajan.pdf
Size:
4.5 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Masters