具氧化侷限結構之全介電質式氮化鎵 垂直共振腔面射型雷射之研究

Abstract

由於氮化鎵材料的發光元件可廣泛應用於指示燈、照明燈、光儲存和光通訊等領域，因此過去幾十年來氮化鎵相關的材料吸引了學術界和業界的目光，並且將其深入研究而在表現上有非常卓越的突破。 我們提出一種具有良好的光學與電流侷限的結構，將p-GaN蝕刻後回填介電質材料SiO2而成的侷限孔徑，並於先前將此結構成功應用在光激發垂直共振腔面射型雷射中，從量測結果發現模態中包含了橫模，由此證實此結構具備光學侷限的能力。本論文旨在設計並製作具備橫向介電質材料侷限的電激發雙介電質型氮化鎵垂直共振腔面射型雷射，之後研究分析此元件之主要特性。 考慮到藍寶石基板本身的電導率和熱傳導率不佳，以及氮化物全磊晶布拉格反射鏡的製作非常困難。我們採用了晶圓結合技術和雷射剝除製作介電質型布拉格反射鏡氮化鎵共振腔發光元件。經過繁雜的製程流程之後，我們從元件量測的頻譜中解析出橫模的存在，證實該介電質侷限結構可以同時達到光學和電流侷限的目的。雖然元件最終沒有達到電激發雷射操作，但量測到窄線寬的頻譜。透過後續製程參數的優化和結構的改良，相信不久之後就能讓元件達到雷射操作的條件。

Due to the widespread applications of GaN-based material, such as indicators, back lighting, ambient lighting, display, optical storage, optical communication, etc., the GaN-based material has attracted much attention of academia and industry. And then, it is widely investigated and have many remarkable breakthroughs in performance. We have designed a kind of structure which shows both great optical and current confinement, and the oxide-confined structure was successfully applied into the optical pumping vertical-cavity surface-emitting laser. The fact that we obtained the transverse mode in the spectrum proves the abilities of optical and current confinement of this structure. The thesis is focus on the design and fabrication of the study of dielectric type GaN-based vertical-cavity surface-emitting lasers with lateral oxide-confined structure. In order to modify the intrinsic properties of the sapphire substrate, which consist of poor electric and thermal conductivity, and overcome the difficulty in the process of the epitaxial DBR, we used the laser lift-off and wafer bonding technique to fabricate a dielectric type GaN-based VCSEL. After the complicated fabrication process, we observed the existence of transverse modes in the measured spectra. This fact proves that the dielectric confined structure can achieve the two targets of optical and current confinement. Although the device did not achieve the laser action, we measured the spectrum with narrow linewidth. In the future, the devices could achieve the laser action after we improve the fabrication parameters and make the structure good quality.