The electroabsorption modulators (EAM) play an important role in the optoelectronic integrated circuits. InGaAs/InAlAs is an excellent material system for fabricating 1.55-£gm EA modulators. Natural high band-offset ( ) ratio structure and the strong exciton effect make this kind of material a good candidate for high saturation power operation and high speed.
In order to design good quantum-well (QW) for electroabsorption, the Vegard¡¦s law is used to obtain the parameters of In1-x-yGaxAlyAs material by interpolating the relevant binary semiconductor material. The bowling factor is included in finding the right bandgap. Using the Resonant Scattering Method, the QW energy levels and electron-hole overlap integrals can be obtained to calculate the optical electroabsorption effects.
In this thesis, the TWEAM based on In1-x-yGaxAlyAs material is also fabricated. In order to get low parasitic capacitance for high-speed operation, a processing called undercut-etching the active region is developed in this work. A selective etching solution (citric acid : H2O2) is used to etch InGaAs layers from InAlAs and the undercut-etching structure InGaAlAs EAM has been successfully fabricated. The processing includes 1)optical waveguide formation with wet etching; 2)n-contact evaporation and contact annealing; 3)mesa etch, PMGI passivation/bridging/planarization; 4)final metallization, cleaving line formation, wafer lapping and device cleaving.
Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0706104-105549 |
Date | 06 July 2004 |
Creators | Lee, chin-Tang |
Contributors | Ann-Kuo chu, Tsong-sheng Lay, Yi-Jen Chiu |
Publisher | NSYSU |
Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
Language | Cholon |
Detected Language | English |
Type | text |
Format | application/pdf |
Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0706104-105549 |
Rights | not_available, Copyright information available at source archive |
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