摘要:
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).
摘要:
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.
摘要:
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).
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.