Freiberger Compound Materials Gmbh

Osram Opto Semiconductors Gmbh

Frank Habel

Ferdinand Scholz

Gunnar Leibiger

Peter Brückner

Stefan Eichler

Matthias Peter

Berndt Weinert

Markus Weyers

Eberhard Richter

Klaus Köhler

Frank Lipski

Martin Klein

Marit Gründer

Frank Brunner

Thomas Wunderer

Barbara Neubert

A III-V-, IV-IV- or II-VI-compound single crystal comprising III-, IV- or II-precipitates and/or unstoichiometrical III-V-, IV-VI-, or II-VI-inclusions, wherein concentration of the respective precipitates and/or inclusions is no more than 1×10cm.

Growth of A-B crystals without crystal lattice curvature

There is provided a template comprising a substrate comprising sapphire and at least one III-N crystal layer, wherein III denotes at least one element of the main group III of the periodic table of the elements, selected from the group of Al, Ga and In, wherein in a region of the at least one III-N layer above the substrate comprises a mask material as an interlayer, wherein the III-N crystal layer of the template is defined by one or both of the following values (i)/(ii) of the deformation &#x3b5;: (i) at room temperature the &#x3b5;value lies in the range of &#x3c;0; and (ii) at growth temperature the &#x3b5;value lies in the range of &#x3b5;&#x2264;0.

Method for producing III-N templates and the reprocessing thereof and III-N template

The present invention relates to a process for the production of III-V-, IV-IV- or II-VI-compound semiconductor crystals. The process starts with providing of a substrate with optionally one crystal layer (buffer layer). Subsequently, a gas phase is provided, which comprises at least two reactants of the elements of the compound semiconductor (II, III, IV, V, VI) which are gaseous at a reaction temperature in the crystal growth reactor and can react with each other at 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, wherein the concentration is selected that high, that crystal formation is possible, wherein by an adding or adjusting of reducing agent and of co-reactant, the activity of the III-, IV- or II-compound in the gas phase is decreased, so that the growth rate of the crystals is lower compared to a state without co-reactant. Therein, the compound semiconductor crystal is deposited at a surface of the substrate, while a liquid phase can form on the growing crystal. Further, auxiliary substances may be added, which can also be contained in the liquid phase, but is only incorporated in low amounts into the compound semiconductor crystal. Herein, 3D- and 2D-growth modes can be controlled in a targeted manner. The addition of auxiliary substances and the presence of a liquid phase favour these means. The product is a single crystal of the respective III-V-, IV-IV- or II-VI-compound semiconductor crystal, which, compared to respectively conventional compound semiconductor crystals has a lower concentration of inclusions or precipitates and nevertheless has no or only a very low curvature.

The present invention relates to a III-N single crystal adhering to a substrate, wherein III denotes at least one element of the third main group of the periodic table of the elements, selected from the group of Al, Ga and In, wherein the III-N single crystal exhibits, within a temperature range of an epitaxial crystal growth, a value (i) of deformation &#x3b5;in the range of &#x3c;0. Additionally or alternatively, the III-N single crystal exhibits at room temperature a value (ii) of deformation &#x3b5;in the range of &#x3c;0.

Processes for producing III-N single crystals, and III-N single crystal

The present invention relates to the production of III-N templates and also the production of III-N single crystals, III signifying at least one element of the third main group of the periodic table, selected from the group of Al, Ga and In. By adjusting specific parameters during crystal growth, III-N templates can be obtained that bestow properties on the crystal layer that has grown on the foreign substrate which enable flawless III-N single crystals to be obtained in the form of templates or even with large III-N layer thickness.

Method for producing III-N single crystals, and III-N single crystal

A semiconductor compound material, preferably a III-N-bulk crystal or a III-N-layer, is manufactured in a reactor by means of hydride vapor phase epitaxy (HVPE), wherein in a mixture of carrier gases a flow profile represented by local mass flow rates is formed in the reactor. The mixture can carry one or more reaction gases towards a substrate. Thereby, a concentration of hydrogen important for the reaction and deposition of reaction gases is adjusted at the substrate surface independently from the flow profile simultaneously formed in the reactor.

Method and device for manufacturing semiconductor compound materials by means of vapour phase epitaxy

A process for producing a doped III-N bulk crystal, wherein III denotes at least one element of the 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 bulk crystal is deposited on a substrate or template in a reactor, and wherein the feeding of at least one dopant into the reactor is carried out in admixture with at least one group III material. In this manner, III-N bulk crystals and III-N single crystal substrates separated therefrom can be obtained with a very homogeneous distribution of dopants in the growth direction as well as in the growth plane perpendicular thereto, a very homogeneous distribution of charge carriers and/or of the specific electric resistivity in the growth direction as well as in the growth plane perpendicular thereto, and a very good crystal quality.

Process for the manufacture of a doped III-N bulk crystal and a free-standing III-N substrate, and doped III-N bulk crystal and free-standing III-N substrate as such

An epitaxial growth process for producing a thick III-N layer, wherein III denotes at least one element of group III of the periodic table of elements, is disclosed, wherein a thick III-N layer is deposited above a foreign substrate. The epitaxial growth process preferably is carried out by HVPE. The substrate can also be a template comprising the foreign substrate and at least one thin III-N intermediate layer. The surface quality is improved by providing a slight intentional misorientation of the substrate, and/or a reduction of the N/III ratio and/or the reactor pressure towards the end of the epitaxial growth process. Substrates and semiconductor devices with such improved III-N layers are also disclosed.

Method for producing III-N layers, and III-N layers or III-N substrates, and devices based thereon

Embodiments of the invention relate to 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.

Process for producing a III-N bulk crystal and a free-standing III-N substrate, and III-N bulk crystal and free-standing III-N substrate

In a process for forming a mask material on a III-N layer, wherein III denotes an element of the group III of the Periodic Table of Elements, selected from Al, Ga and In, a III-N layer having a surface is provided which comprises more than one facet. Mask material is selectively deposited only on one or multiple, but not on all facets. The deposition of mask material may be particularly carried out during epitaxial growth of a III-N layer under growth conditions, by which (i) growth of at least a further III-N layer selectively on a first type or a first group of facet(s) and (ii) a deposition of mask material selectively on a second type or a second group of facet(s) proceed simultaneously. By the process according to the invention, it is possible to produce free-standing thick III-N layers. Further, semiconductor devices or components having special structures and layers can be produced.

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Freiberg, Germany

Frank Habel