The United States of America As Represented by the National Security Agency

Other

University System of Maryland

The United States of America As Represented by the Director of the National Security Agency

Bikash Koley

Frederick Gorr Johnson

Linda M Wasiczko

Mario Dagenais

A method of selectively oxidizing III-V semiconductor material is provided. There is provided a III-V semiconductor system comprising a short-period super lattice (SSL) of N periods of alternating layers of an aluminum-bearing III-V compound semiconductor material and a second III-V semiconductor material where N&gE;2, at least one phosphorous-rich III-V semiconductor layer, and at least one substantially phosphorous-free III-V semiconductor layer between each of the at least one phosphorous-rich layers and the SSL. The III-V semiconductor system is exposed to oxidizing atmosphere to selectively oxidize at least a portion of the SSL.

Method of efficient controllable and repeatable wet oxidation in a phosphorous-rich III-V material system

A method of forming a native oxide from at least one strain-compensated superlattice of Group III-V semiconductor material, where each at least one superlattice includes two monolayers of a Group III-V semiconductor material and at least two monolayers of an aluminum-bearing Group III-V semiconductor material. The method entails exposing each at least one superlattice to a water-containing environment and a temperature of at least about 425 degrees Celsius to convert at least a portion of said superlattice to a native oxide. The native oxide thus formed is useful in electrical and optoelectrical devices, such as lasers.

Method of oxidizing strain-compensated superlattice of group III-V semiconductor

A vertical cavity surface emitting laser that includes a Group III-V semiconductor material substrate; a first Distributed Bragg Reflector mirror, where the first Distributed Bragg Reflector mirror includes at least seven pairs of layers, where each layer has a different index of refraction, where one of the layers is a Group III-V semiconductor material, and where the other layer is a completely oxidized at least one strain-compensated superlattice of Group III-V semiconductor material, where each at least one strain-compensated superlattice includes at least two monolayers of a Group III-V semiconductor material and at least two monolayers of an aluminum-bearing Group III-V semiconductor material; a first Group III-V semiconductor material layer; a first contact; a selectively oxidized at least one strain-compensated superlattice of Group III-V semiconductor material, where each at least one strain-compensated superlattice of Group III-V semiconductor material includes at least two monolayers of a Group III-V semiconductor material and at least two monolayers of an aluminum-bearing Group III-V semiconductor material; a second Group III-V semiconductor material layer; a second contact; and a second Distributed Bragg Reflector mirror that is identical to the first Distributed Bragg Reflector mirror.

Vertical cavity surface emitting laser with oxidized strain-compensated superlattice of group III-V semiconductor

A ridge laser that includes a Group III-V semiconductor material substrate; a first selectively oxidized at least one strain-compensated superlattice of Group III-V semiconductor material; a multiple quantum well active region; a second selectively oxidized at least one strain-compensated superlattice of Group III-V semiconductor material; a Group III-V semiconductor material cap layer; and a contact material. Each at least one strain-compensated superlattice includes at least two monolayers of a Group III-V semiconductor material and at least two monolayers of an aluminum-bearing Group III-V semiconductor material. In the preferred embodiment, the substrate is InP of any type; each selectively oxidized at least one strain-compensated superlattice of Group III-V semiconductor material is InAs/AlAs, where each at least one superlattice of InAs/AlAs includes at least two monolayers of InAs and at least two monolayers of AlAs; the multiple quantum well active region is InGaAsP lattice matched to the InP substrate, the Group III-V semiconductor material cap layer is InP, and the contact material is gold.

Ridge laser with oxidized strain-compensated superlattice of group III-V semiconductor

A cavity-less vertical semiconductor optical amplifier is provided which includes an active region of an intrinsic bulk semiconductor material sandwiched between p- and n-layers of semiconductor materials in which a vertical gain channel of a predetermined confined cross-sectional configuration is formed to constitute an amplification region of the optical amplifier. The amplification region is sandwiched between layers of p- and n-doped layers of linearly graded semiconductor material supplying holes and electrons to the active region upon switching &ldquo;ON&rdquo; of the optical amplifier. Several factors contribute to substantial amplification of an optical signal at a relatively low injection current which include a relatively long active region allowing sufficient single pass gain as well as a strictly confined cross-sectional configuration of the vertical gain channel which reduces the active volume of the amplification region resulting in substantially high gain at a relatively low current. Flattening of the conduction band and valence band profiles allows easy access of the holes and electrons into the active region. The cavity-less vertical semiconductor optical amplifier of the present invention is intended for multidimensional architectural structures for high speed communication.

Growing community of inventors

College Park, MD, United States of America

Bikash Koley