Chinese Academy of Sciences

Technische Universitaet Berlin

Changchun Institute of Optics, Fine Mechanics and Physics

Technische Unversität Berlin

Gunter Larisch

Dieter Bimberg

Sicong Tian

James A Lott

A method of fabricating at least one radiation emitter including fabricating a layer stack that includes a first reflector, an active region, an oxidizable layer, and a second reflector; and locally removing the layer stack, and thereby forming at least one mesa. The mesa includes the first reflector, the active region, the oxidizable layer and the second reflector. Before or after locally removing the layer stack and forming the mesa the following steps are carried out: vertically etching at least three blind holes inside the layer stack, wherein the blind holes vertically extend to and expose the oxidizable layer; and oxidizing the oxidizable layer via the sidewalls of the blind holes in lateral direction. An oxidation front radially moves outwards from each hole. The etching is terminated before the entire oxidizable layer is oxidized, thereby forming at least one unoxidized aperture that is limited by at least three oxidation fronts.

Radiation emitter

An exemplary embodiment of the present invention relates to a method of fabricating at least one radiation emitter comprising the steps of depositing an etch stop layer on a top side of a substrate; depositing a layer stack on the etch stop layer, said layer stack comprising a first contact layer, a first reflector, an active region, a second reflector, and a second contact layer; locally removing the layer stack and the etch stop layer, and thereby forming at least one mesa, said at least one mesa comprising an unremoved section of the etch stop layer and a layered pillar which forms a vertical cavity laser structure based on the unremoved layer stack inside the at least one mesa; depositing a protection material on the top side of the substrate and thereby embedding the entire mesa in the protection material wherein the backside of the substrate remains unprotected; removing the substrate by applying at least one etching chemical that is capable of etching the substrate but incapable or less capable of etching the etch stop layer and the protection material; and removing the etch stop layer and thereby exposing the first contact layer of the at least one layered pillar.

Vertical-cavity surface-emitting laser

A method of fabricating a radiation emitter including fabricating a layer stack that includes a first reflector, at least one intermediate layer, an active region and a second reflector; locally oxidizing the intermediate layer and thereby forming at least one unoxidized aperture; and locally removing the layer stack, and thereby forming a mesa that includes the first reflector, the unoxidized aperture, the active region, and the second reflector. Before or after locally removing the layer stack and forming the mesa: forming at least a first unoxidized aperture and at least a second unoxidized aperture inside the intermediate layer; etching a trench inside the layer stack, the trench defining a first portion and a second portion of the mesa, wherein the trench severs the intermediate layer(s) so that the first aperture is located in the first portion and the second aperture is located in the second portion of the mesa.

A vertical cavity surface emitting laser comprising a first reflector, a second reflector comprising a layer stack of semiconductor or isolating layers, an active region arranged between the first and second reflectors, and an additional layer on top of the layer stack at the light output side, said additional layer forming an output interface of the laser, wherein the refractive index of the additional layer is smaller, equal to or larger than the smallest refractive index of the refractive indices of said layer stack.

Growing community of inventors

Neuenhagen, Germany

Gunter Larisch