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|Title:||Fabrication of novel semiconductor lasers grown by metalorganic chemical vapor deposition|
|Author(s):||Bryan, Robert Porter|
|Doctoral Committee Chair(s):||Coleman, James J.|
|Department / Program:||Electrical and Computer Engineering|
|Degree Granting Institution:||University of Illinois at Urbana-Champaign|
|Subject(s):||Engineering, Electronics and Electrical
Physics, Electricity and Magnetism
|Abstract:||This work describes novel fabrication processes and the advantages of metalorganic chemical vapor deposition (MOCVD) growth on nonplanar substrates which increase the maximum output power of semiconductor lasers when limited by catastrophic optical degradation (COD). Additionally, the characteristics and properties of high energy implantations are discussed as they relate to the fabrication of optoelectronic devices.
Two novel structures are described in which the limitations of COD to the maximum output power are relaxed. In the first approach, a nonplanar substrate and the properties of uniform MOCVD growth are used to form a wide-aperture, index-guided laser array. Optimization of the structure brought about a 40% increase in device efficiency and an output power of over 14 W per uncoated facet. In the second approach, we used a nonplanar substrate to displace the portion of the active region which is in the vicinity of the facets towards the surface of the device. As a result, the optical field propagates through the lower confining layer as it approaches the facet. Lasers incorporating the nonplanar window laser scheme showed an approximately 50% increase in their maximum output power compared to that for conventional lasers.
The demonstration of induced compositional disordering by ion implantation has led to the development of high performance laser diodes and waveguides. Implantation conducted at high energies allows for the direct modification of the optical and electrical properties of devices far from the surface. The electrical properties and the induced compositional disordering of MeV oxygen implantation are discussed. Two high energy implantation masking techniques are described. We used the properties of MeV oxygen implants to fabricate index-guided, buried heterostructure laser diodes. We also investigated the implant temperature dependence of the compositional disordering. The temperature dependence of the intermixing may be explained by the existence of a miscibility gap in the GaAs-AlAs superlattice system.
|Rights Information:||Copyright 1990 Bryan, Robert Porter|
|Date Available in IDEALS:||2011-05-07|
|Identifier in Online Catalog:||AAI9026148|
This item appears in the following Collection(s)
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois
Dissertations and Theses - Electrical and Computer Engineering
Dissertations and Theses in Electrical and Computer Engineering