Abstract: Thin tantalum films having novel microstructures are provided. The films have microstructures such as nanocrystalline, single crystal and amorphous. These films provide excellent diffusion barrier properties and are useful in microelectronic devices. Methods of forming the films using pulsed laser deposition (PLD) and molecular beam epitaxy (MBE) deposition methods are also provided, as are microelectronic devices incorporating these films.

Abstract: The present invention describes a process for the isolation of polyhydroxybutyrate of the formula 1 by growing a culture of Bacillus mycoides RLJ B-017 in a growth medium and a carbon source selected from sucrose, molasses and pineapple waste.

Abstract: Nanostructures and methods of making nanostructures having self-assembled nanodot arrays wherein nanodots are self-assembled in a matrix material due to the free energies of the nanodot material and/or differences in the Gibb's free energy of the nanodot materials and matrix materials.

Abstract: The present invention describes a process for the isolation of polyhydroxybutyrate of the formula 1 by growing a culture of Bacillus mycoides RLJ B-017 in a growth medium and a carbon source selected from sucrose, molasses and pineapple waste.

Abstract: A semiconductor device includes a substrate having a first major surface; a semiconductor device structure over the first surface of the substrate, the device structure comprising an n-type semiconductor layer, and a p-type semiconductor layer over the n-type semiconductor layer; a p-side electrode having a first and a second surface, wherein the first surface is in electrical contact with the p-type semiconductor layer; and a p-side bonding pad over the p-side electrode. Preferably, the semiconductor device further comprises an n-side bonding pad over an n-type semiconductor layer. The p-side and n-side bonding pads each independently includes a gold layer as its top layer and a single or multiple layers of a diffusion barrier under the top gold layer. Optionally, one or more metal layers are further included under the diffusion barrier. Typically, the p-side bonding pad is formed on the p-side electrode.

Abstract: Nanostructures and methods of making nanostructures having self-assembled nanodot arrays wherein nanodots are self-assembled in a matrix material due to the free energies of the nanodot material and/or differences in the Gibb's free energy of the nanodot materials and matrix materials.

Abstract: A method of forming an epitaxial film on a substrate includes growing an initial layer of a film on a substrate at a temperature Tgrowth, said initial layer having a thickness h and annealing the initial layer of the film at a temperature Tanneal, thereby relaxing the initial layer, wherein said thickness h of the initial layer of the film is greater than a critical thickness hc. The method further includes growing additional layers of the epitaxial film on the initial layer subsequent to annealing. In some embodiments, the method further includes growing a layer of the film that includes at least one amorphous island.

Abstract: A method of forming an epitaxial film on a substrate includes growing an initial layer of a film on a substrate at a temperature Tgrowth, said initial layer having a thickness h and annealing the initial layer of the film at a temperature Tanneal, thereby relaxing the initial layer, wherein said thickness h of the initial layer of the film is greater than a critical thickness hc. The method further includes growing additional layers of the epitaxial film on the initial layer subsequent to annealing. In some embodiments, the method further includes growing a layer of the film that includes at least one amorphous island.

Abstract: A method of forming an epitaxial film on a substrate includes growing an initial layer of a film on a substrate at a temperature Tgrowth, said initial layer having a thickness h and annealing the initial layer of the film at a temperature Tanneal, thereby relaxing the initial layer, wherein said thickness h of the initial layer of the film is greater than a critical thickness hc. The method further includes growing additional layers of the epitaxial film on the initial layer subsequent to annealing. In some embodiments, the method further includes growing a layer of the film that includes at least one amorphous island.

Abstract: An optoelectronic device such as an LED or laser which produces spontaneous emission by recombination of carriers (electrons and holes) trapped in Quantum Confinement Regions formed by transverse thickness variations in Quantum Well layers of group III nitrides.

Abstract: Epitaxial gallium nitride is grown on a silicon substrate while reducing or suppressing the formation of a buffer layer. The gallium nitride may be grown directly on the silicon substrate, for example using domain epitaxy. Alternatively, less than one complete monolayer of silicon nitride may be formed between the silicon and the gallium nitride. Subsequent to formation of the gallium nitride, an interfacial layer of silicon nitride may be formed between the silicon and the gallium nitride.

Abstract: An optoelectronic device such as an LED or laser which produces spontaneous emission by recombination of carriers (electrons and holes) trapped in Quantum Confinement Regions formed by transverse thickness variations in Quantum Well layers of group III nitrides.

Abstract: A semiconductor device includes: a substrate; an n-type semiconductor layer over the substrate, the n-type semiconductor layer having a planar top surface; a p-type semiconductor layer extending over a major portion of the n-type semiconductor layer and not extending over an exposed region of the n-type semiconductor layer located adjacent to at least one edge of the planar top surface of the n-type semiconductor layer; a first bonding pad provided on the exposed region of the n-type semiconductor layer; an electrode layer extending over the p-type semiconductor layer; and a second bonding pad on the electrode layer, the bonding pad including a central region for securing an electrical interconnect, and at least one finger-like region protruding from the central region, the finger-like region having a length extending away from the central region and a width that is substantially less than the length. A method for producing a semiconductor device also is described.

Abstract: A semiconductor device includes a substrate having a first major surface; a semiconductor device structure over the first surface of the substrate, the device structure comprising an n-type semiconductor layer, and a p-type semiconductor layer over the n-type semiconductor layer; a p-side electrode having a first and a second surface, wherein the first surface is in electrical contact with the p-type semiconductor layer; and a p-side bonding pad over the p-side electrode. Preferably, the semiconductor device further comprises an n-side bonding pad over an n-type semiconductor layer. The p-side and n-side bonding pads each independently includes a gold layer as its top layer and a single or multiple layers of a diffusion barrier under the top gold layer. Optionally, one or more metal layers are further included under the diffusion barrier. Typically, the p-side bonding pad is formed on the p-side electrode.

Abstract: The present invention describes a process for the isolation of polyhydroybutyrate of the formula 1 1

Abstract: Nanostructures and methods of making nanostructures having self-assembled nanodot arrays wherein nanodots are self-assembled in a matrix material due to the free energies of the nanodot material and/or differences in the Gibb's free energy of the nanodot materials and matrix materials.

Abstract: An improved electrode for a p-type gallium nitride based semiconductor material is disclosed that includes a layer of an oxidized metal and a first and a second layer of a metallic material. The electrode is formed by depositing three or more metallic layers over the p-type semiconductor layer such that at least one metallic layer is in contact with the p-type semiconductor layer. At least two of the metallic layers are then subjected to an annealing treatment in the presence of oxygen to oxidize at least one of the metallic layers to form a metal oxide. The electrodes provide good ohmic contacts to p-type gallium nitride-based semiconductor materials and, thus, lower the operating voltage of gallium nitride-based semiconductor devices.

Abstract: A semiconductor device includes: a substrate; an n-type semiconductor layer over the substrate, the n-type semiconductor layer having a planar top surface; a p-type semiconductor layer extending over a major portion of the n-type semiconductor layer and not extending over an exposed region of the n-type semiconductor layer located adjacent to at least one edge of the planar top surface of the n-type semiconductor layer; a first bonding pad provided on the exposed region of the n-type semiconductor layer; an electrode layer extending over the p-type semiconductor layer; and a second bonding pad on the electrode layer, the bonding pad including a central region for securing an electrical interconnect, and at least one finger-like region protruding from the central region, the finger-like region having a length extending away from the central region and a width that is substantially less than the length. A method for producing a semiconductor device also is described.

Abstract: A method of forming an epitaxial film on a substrate includes growing an initial layer of a film on a substrate at a temperature Tgrowth, said initial layer having a thickness h and annealing the initial layer of the film at a temperature Tanneal, thereby relaxing the initial layer, wherein said thickness h of the initial layer of the film is greater than a critical thickness hc. The method further includes growing additional layers of the epitaxial film on the initial layer subsequent to annealing. In some embodiments, the method further includes growing a layer of the film that includes at least one amorphous island.

Abstract: An improved electrode for a p-type gallium nitride based semiconductor material is disclosed that includes a layer of an oxidized metal and a first and a second layer of a metallic material. The electrode is formed by depositing three or more metallic layers over the p-type semiconductor layer such that at least one metallic layer is in contact with the p-type semiconductor layer. At least two of the metallic layers are then subjected to an annealing treatment in the presence of oxygen to oxidize at least one of the metallic layers to form a metal oxide. The electrodes provide good ohmic contacts to p-type gallium nitride-based semiconductor materials and, thus, lower the operating voltage of gallium nitride-based semiconductor devices.