目前光通訊元件發展上，以工作溫度範圍廣、體積小與低功率消耗的整合性元件為目前發展趨勢。而電致吸收調變雷射(Electroabsorption Modulated Laser, EML)正符合此研究方向，但傳統的EML對溫度特性相當敏感，所以需要一熱電致冷器(Thermoelectric Cooler, TEC) 來控制元件溫度，因此增加了額外的功率消耗與元件封裝後的體積，所以目前以改善EML的溫度特性為光通訊發展的研究方向。
本論文提出以改良式共用主動層 (Modified Share Active Layer) 結構來製作EML，目的在設計一可單獨調整調變器與雷射量子井結構和製程較簡易的EML結構。本論文設計兩種版本的EML結構，並量測其元件在雷射與調變器的光電特性。結構上採用改良式共用主動層式並且配合一次磊晶，另配合脊狀波導的結構增加光場的侷限性。另外主動層材料選用砷化鋁銦鎵(AlGaInAs) ，為近幾年發展非冷卻式雷射所常使用的材料，並且配合工研院的非冷卻雷射式製程技術，以期能做出操作溫度範圍較廣的電致吸收調變雷射。
在量測部分，以雷射電壓-電流關係圖與頻譜分析來判斷雷射特性的好壞，調變器部分由消光比(Extinction ratio, ER)與光電流頻譜圖的量測，來決定電致吸收調變器的好壞。並且量測兩者之間的絕緣特性，以確保兩者互相影響的情形。在製程上，已成功做出改良式共用主動層式的EML元件，並且可比較兩種EML結構設計上的差異，由元件A可驗證電致吸收調變器的特性，可做為操作溫度範圍寬廣的電致吸收調變器！而元件B驗證了DFB雷射與電致吸收調變器積體整合方式的可行性！

Recent development efforts for optical components stress on compactness and low power consumption. Compactness requires higher level integrations. Electroabsorption modulated laser (EML) is one of the most popular integrated optoelectronics developed following the above trend and has become one of the most promising components for short distance optical communications.
This thesis focuses on the design of a process simplified structure for electroabsorption modulated laser. We designed two different structures and analyzed their electrical and optical characteristics. The geometric designs based on ridge waveguide and vertically coupled structures require only one MOCVD regrowth. Furthermore, AlGaInAs material was applied to the active layers for better temperature performance and it is widely used in uncooled laser diode. The existing fabrication technology was supported by Industrial Technology Research Institute (ITRI).
We fabricated two kinds of EMLs, and compared the difference. Device A shows a wide operating temperature range for the modulator. For Device B, the integration of electroabsorption modulator with DFB laser was successfully demonstrated.

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