LIGHT EMITTING ELEMENT HAVING OPTICAL COUPLING LAYER

• Main Authors: YAN LI, LIN CHAO KUN, CHUANG CHIH-WEI
• Format: Patent
• Language: English; Japanese
• Published: 14.01.2016
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To provide an optical coupling layer formed from a thick n-type semiconductor layer required for both appropriate roughing and current diffusion.SOLUTION: An optical coupling layer 235 comprises one or more in-continuous layer that does not incline in terms of composition, and includes, from the n-type III-V group semiconductor layer 230 side, a first layer formed from a III-V group semiconductor material, and a second layer formed from undoped gallium nitride. The first layer and the second layer compose optical-coupling projecting shape. A metal electrode 240 is thicker than the heights of optical-coupling projecting shape, buried between the optical-coupling projections, provided in contact with the first and second layers on the optical coupling projecting shape, and electrically connected with the n-type conductive layer 230. In a direction from an active layer 225 to the n-type III-V group semiconductor layer 230, the optical-coupling projecting shape is narrowed. 【課題】適切な粗面化と電流拡散の両方のために必要となる厚いｎ形半導体層から形成される光結合層を提供する。【解決手段】光結合層２３５は、組成的に傾斜していない１層以上の不連続的な層を含み、ｎ形ＩＩＩ−Ｖ族半導体層２３０側から、ＩＩＩ−Ｖ族半導体材料からなる第１層、及びアンドープ窒化ガリウムからなる第２層、を含み、前記第１層及び前記第２層が光結合突起形状を構成する。金属電極２４０は、前記複数の光結合突起形状の高さよりも厚く、前記光結合突起形状の突起間を埋め込んで形成され、前記光結合突起形状上で前記第１層及び前記第２層に接触して設けられ、前記ｎ形半導体層２３０と電気的に接続される。前記光結合突起形状は、活性層２２５から前記ｎ形ＩＩＩ-Ｖ族半導体層２３０に向かう方向において、その幅が狭くなる形状を有する。【選択図】図２