Abstract: Hydride vapor-phase deposition (HVPE) systems are disclosed. An HVPE hydride vapor-phase deposition system may include a reactant source chamber and a growth chamber containing a susceptor coupled to the reactant source chamber. The reactant source chamber may be configured to create a reactant gas through a chemical reaction between a solid or liquid precursor and a different precursor gas. The reactant source chamber can be configured to operate at a temperature T(M) significantly above room temperature. The reactant gas can be chemically unstable at or near room temperature. The susceptor is configured to receive a substrate and maintain the substrate at a substrate temperature T(S). The growth chamber includes walls can be configured to operate at a temperature T(C) such that T(M), T(S) are greater than T(C).

Abstract: Hydride vapor-phase deposition (HVPE) systems are disclosed. An HVPE hydride vapor-phase deposition system may include a reactant source chamber and a growth chamber containing a susceptor coupled to the reactant source chamber. The reactant source chamber may be configured to create a reactant gas through a chemical reaction between a solid or liquid precursor and a different precursor gas. The reactant source chamber can be configured to operate at a temperature T(M) significantly above room temperature. The reactant gas can be chemically unstable at or near room temperature. The susceptor is configured to receive a substrate and maintain the substrate at a substrate temperature T(S). The growth chamber includes walls can be configured to operate at a temperature T(C) such that T(M), T(S) are greater than T(C).

Abstract: A method for forming an epitaxial layer involves depositing a buffer layer on a substrate by a first deposition process, followed by deposition of an epitaxial layer by a second deposition process. By using such a dual process, the first and second deposition processes can be optimized, with respect to performance, growth rate, and cost, for different materials of each layer. A semiconductor heterostructure prepared by a dual deposition process includes a buffer layer formed on a substrate by MOCVD, and an epitaxial layer formed on the buffer layer, the epitaxial layer deposited by hydride vapor-phase deposition.

Abstract: An epitaxial film of a III-V compound may be formed on a non-native substrate by sequentially forming a plurality of epitaxial layers on the substrate at a growth temperature. By cooling the substrate and each sequentially grown epitaxial layer to a sub-growth temperature prior to resumption of epitaxial growth, stress within the sample (due to thermal mismatch between the substrate and the epitaxial layer) is periodically relieved. Sequential epitaxial growth is combined with system etching to provide an epitaxial layer which not only has a lower propensity to shatter, but also exhibits improved surface morphology. Sequential hydride vapor-phase epitaxy using HCl as both source gas and etchant, allows integration of sequential deposition and system etching into a single process.

Abstract: A method for the production of a crack-free epitiaxial film having a thickness greater than that which can be achieved by continuous epitaxial crystal growth. This epitaxial film can be used as is in a device, used as a substrate platform for further epitaxy, or separated from the initial substrate material and used as a free-standing substrate platform. The method utilizes a defect-rich initial layer that absorbs epitaxially derived stresses and another layer, which is not defect-rich, which planarizes the crystal growth front, if necessary and provides high quality epitaxial region near the surface.

Abstract: A hybrid deposition system includes a reactor chamber, at least one heating unit, a first reagent gas source, a metallo-organic source, a second reagent gas source, and a valve unit for stopping flow of gas from the metallo-organic source. The hybrid incorporates features of both metal-organic chemical vapor deposition (MOCVD) and hydride vapor-phase epitaxy (HVPE). The hybrid system may be operated in MOCVD mode, in HVPE mode, or in both MOCVD and HVPE mode simultaneously. The system may be switched between deposition modes without interrupting deposition, or removing the sample from the reactor chamber. The at least one heating unit may be moved relative to the reactor chamber, or vice versa, for easily and rapidly adjusting the temperature of the reactor chamber. A method for forming at least one epitaxial layer of a III-V compound on a non-native substrate in which deposition is performed by two different techniques in the same reactor chamber.

Abstract: A method for the production of crack-free Group III-Nitride layers is disclosed. The method proceeds by growing a crack-free first layer of Group III-Nitride on a starting substrate. A partial to complete loss of coherency is then achieved between a lattice of the first layer and a lattice of the starting substrate. A second layer is grown to form a composite layer that includes the first layer and the second layer such that the first layer is between the second layer and the substrate. The starting substrate may then be completely separated from the composite layer to produce the freestanding crack-free Group III-Nitride layer.

Abstract: A reaction assembly of a vapor-phase deposition system includes a reaction chamber leading to a gullet outlet, and a sheath leading to a sheath outlet. The gullet outlet and the sheath outlet at the distal end of the reaction assembly, the distal end including a compound nozzle. The reaction assembly generates a compound gas stream for projection from the compound nozzle towards a target substrate. The compound gas stream includes a reagent gas stream and a sheath gas stream, wherein the sheath gas stream at least partially envelopes the reagent gas stream. Methods for generating and delivering a compound gas stream, and for performing vapor-phase deposition, are also disclosed.

Abstract: A method for forming a relatively thick epitaxial film of a III-V compound on a non-native substrate involves sequentially forming a plurality of epitaxial layers on the substrate at a growth temperature. By cooling the substrate and each sequentially grown epitaxial layer to a sub-growth temperature prior to resumption of epitaxial growth, stress within the sample (due to thermal mismatch between the substrate and the epitaxial layer) is periodically relieved. Sequential epitaxial growth is combined with system etching to provide an epitaxial layer which not only has a lower propensity to shatter, but also exhibits improved surface morphology. Sequential hydride vapor-phase epitaxy using HCl as both source gas and etchant, allows integration of sequential deposition and system etching into a single process.

Abstract: A scrubber assembly for removal of water soluble and/or alkaline gases from an exhaust stream uses a scrubber mixture contained within at least one scrubber vessel. Preferably the scrubber mixture include a liquid phase including an aqueous acid solution, and solid phase including a solid organic acid. Preferably, the scrubber mixture includes a solid carboxylic acid having low toxicity and low corrosiveness to system components. In one embodiment, a plurality of scrubber vessels, each containing the scrubber mixture are connected in series. The scrubber assembly may further include an indicator tank containing an indicator mixture. The pH of the scrubber mixture and/or indicator mixture may be monitored, thereby making operation of the system not only simpler and more reliable, but also more efficient. A method for removal of water soluble and/or alkaline gases from an exhaust stream is also disclosed.

Abstract: A reaction assembly of a vapor-phase deposition system includes a reaction chamber leading to a gullet outlet, and a sheath leading to a sheath outlet. The gullet outlet and the sheath outlet at the distal end of the reaction assembly, the distal end including a compound nozzle. The reaction assembly generates a compound gas stream for projection from the compound nozzle towards a target substrate. The compound gas stream includes a reagent gas stream and a sheath gas stream, wherein the sheath gas stream at least partially envelopes the reagent gas stream. Methods for generating and delivering a compound gas stream, and for performing vapor-phase deposition, are also disclosed.

Abstract: An n-doped, high quality gallium nitride substrate suitable for further device or epitaxial processing, and method for making the same. The nitride substrate is produced by epitaxial deposition of first metal nitride layer on a non-native substrate followed by a second deposition of metal nitride. During the second deposition of metal nitride, a liquid metal layer is formed at the interface of the non-native substrate and the metal nitride layer form. The formed metal nitride layer may be detached from the non-native substrate to provide an metal nitride substrate with a high quality inverse surface. A epitaxial metal nitride layer may be deposited on the inverse surface of metal nitride substrate. The metal nitride substrate and the epitaxial metal nitride layer thereon may be deposited using the same hydride vapor-phase epitaxy system.

Abstract: A vapor-phase deposition system includes one or more channel units for promoting the downstream passage of reagent gases. A reactor of a vapor-phase deposition system may include one or more channels to promote passage of reagent gases beneath a susceptor stage. A susceptor, for arrangement within a reactor during epitaxial growth on a substrate, may include a truncated stage and a truncation side. The substrate may be aligned with a lower edge of the truncated stage, thereby avoiding chemical deposition on surfaces upstream of the substrate. One or more channels of the susceptor promote the downstream passage of reagent gases within the reactor. Methods for vapor-phase deposition and for promoting downstream passage of reagent gases within a reactor are also disclosed.

Abstract: A method for producing thick, high quality GaN substrates uses an epitaxially deposited film is used as a substrate material for further device or epitaxial processing. The film is deposited using an epitaxial technique on a thin substrate called the disposable substrate. The deposited film is thick enough so that upon cooling the thermal mismatched strain is relieved through cracking of the lower disposable substrate and not the newly deposited epitaxy. The epitaxial film now becomes a platform for either further epitaxial deposition or device processing.

Abstract: A method for removing particulate matter from an exhaust stream, in which the exhaust stream is passed through a particle trap assembly. The trap assembly includes a particle trap having a trap inlet, a filter region located downstream from the trap inlet, and an upstream portion located upstream from the filter region. The cross-sectional area of the upstream portion is preferably at least as great as the cross-sectional area of the filter region. The particle trap may be operably coupled directly to a source of an exhaust stream via a connector unit. The trap assembly may include a heating unit for heating at least a portion of the trap assembly, and a bellows-like connector unit.

Abstract: A concept and process is disclosed by which an epitaxially deposited film is removed from its substrate at elevated temperatures to inhibit thermal mismatch strain induced defect generation in the epitaxial layer. The process occurs by gas phase reactions of an intermediate layer purposely deposited to react with a component in the gas stream during or after epitaxial growth. While the concept of an intermediate layer has been used extensively to improve the crystal quality of the epitaxial layer this is not the purpose of this interlayer. Although this interlayer may aid in nucleation of the epitaxial layer, the objective is to separate the epitaxial material on top of the interlayer from the substrate below the interlayer at or near the growth temperature to reduce the effects of the thermal mismatch between the substrate and epitaxial layers. An application is an addition to the above invention. A thick epitaxially deposited film can now be removed from its substrate at elevated temperatures.