摘要:
The invention describes methods for producing a doped III-N solid crystal, where III denotes at least one element of main group III of the periodic system, selected from Al, Ga and In, wherein the doped crystalline III-N layer or the doped III-N solid crystal is deposited on a substrate or template in a reactor, and wherein at least one dopant is fed into the reactor in a mixture with at least one group III material. In this way, it is possible to obtain III-N solid crystals and III-N single-crystal substrates singulated therefrom, each having a highly homogeneous distribution of the dopant in the growth direction and also in the growth plane perpendicular thereto. It is correspondingly possible to provide a highly homogeneous distribution of charge carriers and/or of electrical resistivity in the growth direction and also in the growth plane perpendicular thereto. Furthermore, it is possible to obtain a very good crystal quality.
摘要:
Durch ein beschriebenes Verfahren zum Herstellen von geglättetem III-N, insbesondere von geglättetem III-N-Substrat oder III-N-Template, wobei III mindestens ein Element der Gruppe III. des Periodensystems bedeutet, ausgewählt aus Al, Ga und In, ist es möglich, großflächige III-N-Substrate oder III-N-Templates mit Durchmessern von mindestens 40mm mit einer Homogenität von sehr geringer Oberflächenrauhigkeit über die gesamte Substrat- bzw. Waferoberfläche bereitzustellen. So beträgt bei einem Mapping der Waferoberfläche mit einem Weißlichtinterferometer die Standardabweichung der rms-Werte 5% oder weniger. Diese Eigenschaft ist gleichzeitig erhältlich mit einer sehr guten Kristallqualität an der Oberfläche oder oberflächennaher Bereiche, beispielsweise messbar durch Rockingkurvenmappings und/oder Mikro-Ramanmappings.
摘要:
The invention describes a process for producing a III -N bulk crystal, wherein III denotes at least one element selected from group III of the periodic system, selected from Al, Ga and In, wherein the III -N bulk crystal is grown by vapor phase epitaxy on a substrate, and wherein the growth rate is measured in real-time. By actively measuring and controlling the growth rate in situ, i.e. during the epitaxial growth, the actual growth rate can be maintained essentially constant. In this manner, III-N bulk crystals and individualized III-N single crystal substrates separated therefrom, which respectively have excellent crystal quality both in the growth direction and in the growth plane perpendicular thereto, can be obtained.
摘要:
The invention relates to a method for producing III-V-, IV- IV- or II-VI- compound semiconductor crystals. The method starts with the provision of a substrate having optionally one crystal layer (buffer layer). This is followed by the provision of a gas phase which has at least two reactants of elements for the compound semiconductor (II, III, IV, V, VI), the reactants being gaseous at a reaction temperature in the crystal growth reactor and being capable of reacting together under the selected reactor conditions. The ratio of the concentrations of two of the reactants is adjusted such that the compound semiconductor crystal can crystallize from the gas phase, a concentration being chosen that is sufficiently high to facilitate crystal formation and the activity of the III-, IV- or II-compound being reduced in the gas phase by the addition or adjustment of reducing agent and co-reactant, such that the growth rate of the crystal is lower compared to a state without the co-reactant. The compound semiconductor crystal is deposited on a surface of the substrate, whilst a liquid phase can form on the growing crystal. In addition, auxiliary substances can be added which can also be contained in the liquid phase but which are only incorporated in negligible amounts into the compound semiconductor crystal. This allows 3D and 2D growth modes to be controlled selectively. The addition of auxiliary substances and the presence of a liquid phase promote these measures. The product is a single crystal of a III-V-, IV-IV- or II-VI-compound semiconductor crystal, which contains lower concentrations of inclusions or precipitates compared to conventional compound semiconductor crystals and which nevertheless has no or only a negligible curvature.
摘要:
The invention relates to the production of a compound semiconductor material, preferably a III-N bulk crystal, or a III-N layer, by means of hydride gas phase epitaxy (HVPE) in a reactor, in which a flow profile represented by local mass flow rates is formed in the reactor in a mixture of carrier gases. The mixture can include one or more reaction gases in the direction toward a substrate. For this purpose, a concentration of hydrogen critical for the reaction and precipitation of the reaction gases is adjusted on the surface of the substrate independently from the flow profile formed in the reactor.
摘要:
The invention relates to a method for producing smooth III-N, particularly smooth III-N substrate or III-N template, III meaning at least one element from group III of the periodic table selected among Al, Ga, and In. A smoothing means comprises cubic boron nitride as an abrasive particle. Said method makes it possible to create large-area III-N substrates or III-N templates that have a minimum diameter of 40 mm with a homogeneous very low surface roughness across the entire surface of the substrate or wafer. For example, the standard deviation of the rms values is 5 percent or less when the wafer surface is mapped by means of a white light interferometer. Said property can be obtained along with very good crystal quality on the surface or in areas near the surface, said quality being measured by means of rocking curve mapping and/or micro-Raman mapping, for example.
摘要:
The invention describes a process for producing a III -N bulk crystal, wherein III denotes at least one element selected from group III of the periodic system, selected from Al, Ga and In, wherein the III -N bulk crystal is grown by vapor phase epitaxy on a substrate, and wherein the growth rate is measured in real-time. By actively measuring and controlling the growth rate in situ, i.e. during the epitaxial growth, the actual growth rate can be maintained essentially constant. In this manner, III-N bulk crystals and individualized III-N single crystal substrates separated therefrom, which respectively have excellent crystal quality both in the growth direction and in the growth plane perpendicular thereto, can be obtained.