Nitek, Inc.

Medical University of South Carolina

Asif Khan

Vinod Adivarahan

Qhalid Fareed

Alexander Lunev

Iftikhar Ahmad

Bin Zhang

Rubina Khan

A conical supply tube is provided, along with deposition systems using such a tube and methods of its use. The conical supply tube includes a conical head formed from a hollow structure defining a having a fitting end and an opposite, shower end, with the fitting end has an initial diameter that is less than a diameter at the shower end. A MOCVD chamber is also generally provided that includes such a conical supply tube and a susceptor configured to hold a substrate facing the shower end of the conical supply tube. Methods are provided for growing a group III nitride layer on a surface of a substrate.

MOCVD system injector for fast growth of AlInGaBN material

Methods are provided for forming AlInGaBN material. The method can include growing an AlInGaBN layer on a substrate; removing a portion of the AlInGaBN layer from the substrate to define a plurality of AlInGaBN islands on the substrate; and growing a highly doped-AlInGaBN layer on each of the AlInGaBN islands.

Double mesa large area AlInGaBN LED design for deep UV and other applications

An MOCVD system for growing a semiconductor layer on a substrate is provided. The MOCVD system includes an MOCVD growth chamber defined by a jacket having an interior surface and an exterior surface; a water flow chamber surrounding an exterior surface of the jacket of the MOCVD growth chamber; an electronic control system, wherein the electronic control system facilitates pulsed growth of the semiconductor layer; a supply tube comprising a head formed from a hollow structure defining a fitting end and an opposite, shower end, wherein the fitting end has an initial diameter that is less than a diameter at the shower end; and a susceptor configured to hold the substrate and facing the shower end of the supply tube, wherein the MOCVD system operates at a temperature greater than or equal to 1500&#xb0; C.

MOCVD system for growth of III-nitride and other semiconductors

A template for a semiconductor device is made by providing an AGN substrate, growing a first layer of Group III nitrides on the substrate, depositing a thin metal layer on the first layer, annealing the metal such as gold so that it agglomerates to form a pattern of islands on the first layer; transferring the pattern into the first layer by etching then removing excess metal; and then depositing a second Group III nitride layer on the first layer. The second layer, through lateral overgrowth, coalesces over the gaps in the island pattern leaving a smooth surface with low defect density. A Group III semiconductor device may then be grown on the template, which may then be removed. Chlorine gas may be used for etching the pattern in the first layer and the remaining gold removed with aqua regia.

Semiconductor and template for growing semiconductors

MOSHFET devices are provided, along with their methods of fabrication. The MOSHFET device can include a substrate; a multilayer stack on the substrate; a ultra-thin barrier layer on the multilayer stack, wherein the ultra-thin barrier layer has a thickness of about 0.5 nm to about 10 nm; a dielectric, discontinuous thin film layer on portions of the ultra-thin barrier layer, wherein the dielectric, discontinuous thin film layer comprises SiO; a plurality of source electrodes and drain electrodes formed directly on the ultra-thin barrier layer in an alternating pattern such that the dielectric, discontinuous thin film layer is positioned between adjacent source electrodes and drain electrodes; a plurality of gate electrodes on the dielectric, discontinuous thin film layer; and a gate interconnect electrically connecting the plurality of gate electrodes.

Multi-finger large periphery AlInN/AlN/GaN metal-oxide-semiconductor heterostructure field effect transistors on sapphire substrate

Methods for forming a HEMT device are provided. The method includes forming an ultra-thin barrier layer on the plurality of thin film layers. A dielectric thin film layer is formed over a portion of the ultra-thin barrier layer to leave exposed areas of the ultra-thin barrier layer. A SAG S-D thin film layer is formed over the exposed areas of the ultra-thin barrier layer while leaving the dielectric thin film layer exposed. The dielectric thin film layer is then removed to expose the underlying ultra-thin barrier layer. The underlying ultra-thin barrier layer is treating with fluorine to form a treated area. A source and drain is added on the SAG S-D thin film layer, and a dielectric coating is deposited over the ultra-thin barrier layer treated with fluorine such that the dielectric coating is positioned between the source and the drain.

Selectively area regrown III-nitride high electron mobility transistor

An improved process for forming a UV emitting diode is described. The process includes providing a substrate. A super-lattice is formed directly on the substrate at a temperature of at least 800 to no more than 1,300&#xb0; C. wherein the super-lattice comprises AlInGaN wherein 0&#x3c;x&#x2266;1, 0&#x2266;y&#x2266;1 and 0&#x3c;x+y&#x2266;1. A first conductive layer with a first type of conductivity is formed on the super-lattice wherein the first conductive layer comprises AlInGaN wherein 0&#x3c;x&#x2266;1, 0&#x2266;y&#x2266;1 and 0&#x3c;x+y&#x2266;1. A quantum well region is formed on the first conductive layer wherein the quantum well region comprises AlInGaN wherein 0&#x3c;x&#x2266;1, 0&#x2266;y&#x2266;1 and 0&#x3c;x+y&#x2266;1. A second conductive layer is formed on the quantum well with a second type of conductivity wherein the second conductive layer comprises AlInGaN wherein 0&#x3c;x&#x2266;1, 0&#x2266;y&#x2266;1 and 0&#x3c;x+y&#x2266;1. A first metal contact is formed in electrical contact with the first conductive layer and a second metal contact is formed in electrical contact with the second conductive layer.

High power ultraviolet light emitting diode with superlattice

The present invention is generally directed to methods of selectively doping a substrate and the resulting selectively doped substrates. The methods include doping an epilayer of a substrate with the selected doping material to adjust the conductivity of either the epilayers grown over a substrate or the substrate itself. The methods utilize lithography to control the location of the doped regions on the substrate. The process steps can be repeated to form a cyclic method of selectively doping different areas of the substrate with the same or different doping materials to further adjust the properties of the resulting substrate.

Selectively doped semi-conductors and methods of making the same

Ultraviolet light emitting illuminator, and method for fabricating same, comprises an array of ultraviolet light emitting diodes and a first and second terminal. When an alternating current is applied across the first and second terminals and thus to each of the diodes, the illuminator emits ultraviolet light at a frequency corresponding to that of the alternating current. The illuminator includes a template with ultraviolet light emitting quantum wells, a first buffer layer with a first type of conductivity and a second buffer layer with a second type of conductivity, all deposited preferably over strain-relieving layer. A first and second metal contact are applied to the semiconductor layers having the first and second type of conductivity, respectively, to complete the LED. The emission spectrum ranges from 190 nm to 369 nm. The illuminator may be configured in various materials, geometries, sizes and designs.

Ultraviolet light emitting diode with AC voltage operation

An ultra-violet light-emitting device and method for fabricating an ultraviolet light emitting device,, (LED or an LD) with an AlInGaN multiple-quantum-well active region,, exhibiting stable cw-powers. The device includes a non c-plane template with an ultraviolet light-emitting structure thereon. The template includes a first buffer layer,, on a substrate,, then a second buffer layer,, on the first preferably with a strain-relieving layer,, in both buffer layers. Next there is a semiconductor layer having a first type of conductivity,, followed by a layer providing a quantum-well region,. Another semiconductor layer,, having a second type of conductivity is applied next. Two metal contacts,and, are applied to this construction, one to the semiconductor layer having the first type of conductivity and the other to the semiconductor layer having the second type of conductivity, to complete the light emitting device.

Non-polar ultraviolet light emitting device and method for fabricating same

A vertically conducting LED comprising, in a layered arrangement: a highly thermally conductive submount wherein the highly conductive submount has a thermal conductivity of at least 100 W/mK; a p-type layer comprising AlInGaN wherein 0&#x2266;x&#x2266;1 and 0&#x2266;y&#x2266;1; a quantum well layer comprising AlInGaN wherein 0&#x2266;x&#x2266;1 and 0&#x2266;y&#x2266;1; an n-type layer comprising AlInGaN wherein 0&#x2266;x&#x2266;1 and 0&#x2266;y&#x2266;1; and an n-type contact layer wherein the LED has a peak emission at 200-365 nm.

High power ultraviolet light sources and method of fabricating the same

A vertical geometry light emitting diode with a strain relieved superlattice layer on a substrate comprising doped AlInGaN. A first doped layer is on the strain relieved superlattice layer AlInGaN and the first doped layer has a first conductivity. A multilayer quantum well is on the first doped layer comprising alternating layers quantum wells and barrier layers. The multilayer quantum well terminates with a barrier layer on each side thereof. A second doped layer is on the quantum well wherein the second doped layer comprises AlInGaN and said second doped layer has a different conductivity than said first doped layer. A contact layer is on the third doped layer and the contact layer has a different conductivity than the third doped layer. A metallic contact is in a vertical geometry orientation.

Vertical deep ultraviolet light emitting diodes

A light emitting device with a template comprising a substrate and a nested superlattice. The superlattice has AlInGaN wherein 0&#x2266;x&#x2266;&#x3b1; and 0&#x2266;y&#x2266;1 with x increasing with distance from said substrate. An ultraviolet light-emitting structure on the template has a first layer with a first conductivity comprising AlInGaN wherein &#x3b1;&#x2266;x; a light emitting quantum well region above the first layer comprising AlInGaN wherein &#x3b1;&#x2266;x&#x2266;b; and a second layer over the light emitting quantum well with a second conductivity comprising AlInGaN wherein b&#x2266;x. The light emitting device also has a first electrical contact in electrical connection with the first layer, a second electrical contact in electrical connection with the second layer; and the device emits ultraviolet light.

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Irmo, SC, United States of America

Asif Khan