Structure of Vertical Cavity Surface Emitting Laser

A VCSEL structure, comprising:

• a substrate;
• a first mirror layer, located on the substrate;
• an active region, located on the first mirror layer;
• a second mirror layer, located on active region and having an upper surface;
• an oxide layer, located in the second mirror layer and having a central opening;
• a mesa, located on the substrate, structured by at least a portion of the first mirror layer, the active region, the second mirror layer and the oxide layer;
• an output window being included in a central area of a top surface of the mesa;
• the output window is corresponding to the central opening;
• an isolation trench, located in and surrounding at least a portion of a periphery of the mesa;
• said isolation trench penetrating downward through the second mirror layer, the oxide layer and the active region from the top surface of the mesa;
• the isolation trench being filled with a dielectric material;
• a metal layer, located on the top surface of the mesa and circling at least a portion of an outer periphery of the output window;
• said metal layer at least including an inner rim contacting the upper surface of the second mirror layer;
• a diameter of the output window being defined by an inner diameter of the inner rim of the metal layer;
• and
• an ion-implanted region, at least located in the mesa;
• wherein:
• the ion-implanted region is an insulating area formed by implanting a plurality of non-conductive elements in the second mirror layer;
• the ion-implanted region extends downward from the upper surface of the second mirror layer into the second mirror layer by a predetermined depth;
• in addition, the ion-implanted region in the mesa is located between the output window and the isolation trench, and is surrounding at least a part of the outer periphery of the output window;
• when viewing downwardly from top of the mesa, the ion-implanted region has an arc-shaped inner rim, an arc-shaped outer rim and at least one conductive channel extends outward from the arc-shaped inner rim toward the arc-shaped outer rim by a predetermined length in such a manner that, an outer end portion of the conductive channel is at least outwardly exceeding the arc-shaped inner rim of the metal layer;
• there are no said non-conductive elements being implanted in the conductive channel;
• the metal layer located above the conductive channel directly contacts the upper surface of the second mirror layer;
• the diameter of the arc-shaped inner rim of the ion-implanted region is smaller than the inner diameter of the inner rim of the metal layer;
• that is, the diameter of the arc-shaped inner rim of ion-implanted region is smaller than the diameter of the output window.