The work of this thesis includes designs, molecular beam epitaxy (MBE) growths and optical study of electro-absorption modulator (EAM) structures. Three EAM structures are designed near 1.5 um : symmetric, asymmetric multiple quantum wells (MQWs) of TE polarization, and polarization insensitive MQWs. For symmetric and asymmetric MQWs simulation of TE polarization, their red-shift are 31 nm and 50 nm, respectively, as the electric field decrease from -40 kV/cm to -120 kV/cm. For polarization insensitive MQWs, we use the strained quantum-well concept to achieve same transition energy and absorption.
After growth by MBE system, the samples were fabricated in mesa type by photolithography and wet etching. For symmetric and asymmetric quantum wells of TE polarization¡Gthe red-shift are 16 nm and 49 nm, respectively, as the bias decrease form 0-1 volt to 0-6 volt. Because of small ¡µn near subband transition energy, these two samples exhibit small chirp parameter. However, the photoluminescence (PL) and photocurrent spectra of these two ones were not near 1.5 um and obvious absorption edge. The possible reason is that the molecular beam flux have changed during growth. For polarization insensitive MQWs, the PL spectra shows 1494 nm, which only 25.6 nm differ from our design. Also, the photocurrent spectra of TE and TM polarization nearly exhibit same transition energy and have small chirp parameter.
Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0630103-023051 |
Date | 30 June 2003 |
Creators | Lu, Sho-Shou |
Contributors | Lung-Han Peng, Tao-Yuan Chang, Tsong-Sheng Lay, Yi-Jen Chiu, Shoou-Jinn Chang |
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-0630103-023051 |
Rights | unrestricted, Copyright information available at source archive |
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