Abstract: The present disclosure relates to the field of epitaxial structures for microelectronic device formation, particularly to heavily doped, substrates having a compensation component embedded along the dopant to prevent bowing of the substrate during deposition of an epitaxial layer.

Abstract: A semiconductor device receiving as input a radio frequency signal having a frequency of 500 MHz or more and a power of 20 dBm or more is provided. The semiconductor device includes: a silicon substrate; a silicon oxide film formed on the silicon substrate; a radio frequency interconnect provided on the silicon oxide film and passing the radio frequency signal; a fixed potential interconnect provided on the silicon oxide film and placed at a fixed potential; and an acceptor-doped layer. The acceptor-doped layer is formed in a region of the silicon substrate. The region is in contact with the silicon oxide film. The acceptor-doped layer is doped with acceptors.

Abstract: A semiconductor device according to one embodiment includes: a semiconductor layer formed on a semiconductor substrate; a gate electrode formed on the semiconductor layer via a gate insulating film; an impurity diffusion suppression layer formed between the semiconductor substrate and the semiconductor layer and including a C-containing Si-based crystal containing a first impurity, the C-containing Si-based crystal being configured to suppress diffusion of a second impurity having a p-type conductivity type, and the C-containing Si-based crystal with the first impurity having a function of suppressing generation of fixed charge in the C-containing Si-based crystal; and p-type source/drain regions formed in the semiconductor substrate, the impurity diffusion suppression layer and the semiconductor layer in sides of the gate electrode, the p-type source/drain region having an extension region in the semiconductor layer and containing the second impurity.

Abstract: The present invention discloses a pseudo buried layer, a deep hole contact and a bipolar transistor, and also discloses a manufacturing method of a pseudo buried layer, including: etching a silicon substrate to form an active region and shallow trenches; sequentially implanting phosphorous ion and arsenic ion into the bottom of the shallow trenches to form phosphorus impurity regions and arsenic impurity regions; conducting thermal annealing to the phosphorus impurity regions and arsenic impurity regions. The implantation of the pseudo buried layer, adopting phosphorous with rapid thermal diffusion and arsenic with slow thermal diffusion, can improve the impurity concentration on the surface of the pseudo buried layers, reduce the sheet resistance of the pseudo buried layer, form a good ohmic contact between the pseudo buried layer and a deep hole and reduce the contact resistance, and improve the frequency characteristic and current output of triode devices.

Abstract: A method of manufacturing a silicon wafer provides a silicon wafer which can reduce the precipitation of oxygen to prevent a wafer deformation from being generated and can prevent a slip extension due to boat scratches and transfer scratches serving as a reason for a decrease in wafer strength, even when the wafer is provided to a rapid temperature-rising-and-falling thermal treatment process.

Abstract: A silicon carbide semiconductor element and a manufacturing method thereof are disclosed in which a low contact resistance is attained between an electrode film and a wiring conductor element, and the wiring conductor element is hardly detached from the electrode film. In the method, a nickel film and a nickel oxide film are laminated in this order on a surface of an n-type silicon carbide substrate or an n-type silicon carbide region of a silicon carbide substrate, followed by a heat treatment under a non-oxidizing condition. The heat treatment transforms a portion of the nickel film into a nickel silicide film. Then, the nickel oxide film is removed with hydrochloric acid solution, and subsequently, a nickel aluminum film and an aluminum film are laminated in this order on a surface of the nickel silicide film.

Abstract: A semiconductor device and a manufacturing method thereof is disclosed in which the semiconductor device includes a p-type anode layer formed by a transition metal acceptor transition, and the manufacturing process is significantly simplified without the breakdown voltage characteristics deteriorating. An inversion advancement region inverted to a p-type by a transition metal acceptor transition, and in which the acceptor transition is advanced by point defect layers, is formed on the upper surface of an n-type drift layer. The inversion advancement region configures a p-type anode layer of a semiconductor device of the invention. The transition metal is, for example, platinum or gold. An n-type semiconductor substrate with a concentration higher than that of the n-type drift layer is adjacent to the lower surface of the n-type drift layer.

Abstract: The semiconductor device of the present invention includes: a gate insulating film formed on a semiconductor region of a first conductivity type; a gate electrode formed on the gate insulating film; and a channel doped layer of the first conductivity type formed in the semiconductor region beneath the gate electrode. The channel doped layer contains carbon as an impurity.

Abstract: An integrated circuit with improved intrinsic gettering ability is described, having a bulk micro-defect (BMD) density of 3.85×105-3.38×109/cm3 through first and second annealing steps. The first annealing step is performed at a first temperature in an atmosphere containing at least one of oxygen gas and nitrogen gas. The second annealing step is performed at a second temperature higher than the first temperature in the atmosphere.

Abstract: This method of manufacturing a silicon wafer has a step of preparing a wafer, in which a surface of the silicon wafer is surface-treated, a step of setting stress, in which the stress S (MPa) subjected on the wafer is set, a step of inspecting, in which a defect on a surface of the wafer is inspected, and a step of determining, in which the wafer is evaluated if the wafer satisfies a criterion. In this method, it is possible to manufacture a wafer with cracking resistance even if it is subjected to a millisecond annealing by the FLA annealing treatment.

Abstract: A circuit module comprises a die attach pad with a surface and a plurality of leads surrounding the surface. A nonconductive adhesive is on the surface. A plurality of electronic circuit dies are on the surface of the die attach pad. Each die has a top surface and a bottom surface with the bottom surface on the adhesive. The top surface has a plurality of bonding pads. A first electronic circuit die has at least one routing path of a conductive material connecting a first bonding pad to a second bonding pad. A first bonding wire connects a bonding pad of a second electronic circuit die to the first bonding pad of the first electronic die. A second bonding wire connects the second bonding pad of the first electronic circuit die to a lead. Where one of the dies contains vertical circuit element, where a doped layer forms a terminal along the bottom surface of the layer, a trench filled with doped polysilicon extends from the top surface to the terminal to connect to the terminal.

Abstract: The semiconductor of the present invention has iron sulfide and a forbidden band control element contained in the iron sulfide. The forbidden band control element has a property capable of controlling the forbidden band of iron sulfide on the basis of the number density of the forbidden band control element in the iron sulfide. An n-type semiconductor is manufactured by incorporating a group 13 element of the IUPAC system into iron sulfide. Moreover, a p-type semiconductor is manufactured by incorporating a group Ia element into iron sulfide. A semiconductor junction device or a photoelectric converter is manufactured by using the n-type semiconductor and the p-type semiconductor.

Abstract: In a method of manufacturing a semiconductor device, forming a film of amorphous Si on a substrate including an insulating upper surface; injecting a first impurity of a first conductivity in a first region and a second region of the film; crystallizing the film by melting and solidifying the film and activating the first impurity by scanning a first laser light in a first direction and radiating the first laser light over the film; injecting a second impurity of a second conductivity at a higher concentration than the first impurity, the second impurity being a lighter element than the first impurity in the first region with masking the second region; and activating the second impurity.

Abstract: A conventional semiconductor device, for example, a lateral PNP transistor has a problem that it is difficult to obtain a desired current-amplification factor while maintaining a breakdown voltage characteristic without increasing the device size. In a semiconductor device, that is a lateral PNP transistor, according to the present invention, an N type epitaxial layer is formed on a P type single crystal silicon substrate. The epitaxial layer is used as a base region. Moreover, molybdenum (Mo) is diffused in the substrate and the epitaxial layer. With this structure, the base current is adjusted, and thereby a desired current-amplification factor (hFE) of the lateral PNP transistor is achieved.

Abstract: A semiconductor component and a method for manufacturing such a semiconductor component which has a resistance behavior which depends heavily on the temperature. This resistance behavior is obtained by a special multi-layer structure of the semiconductor component, one layer being designed in such a way that, for example, multiple p-doped regions are present in an n-doped region, said regions being short-circuited on one side via a metal-plated layer. For example, the semiconductor component may be used for reducing current peaks, by being integrated into a conductor. In the cold state, the semiconductor component has a high resistance which becomes significantly lower when the semiconductor component is heated as a result of the flowing current.

Abstract: Phosphorous-comprising dopants, methods for forming phosphorous-doped regions in a semiconductor material, and methods for fabricating phosphorous-comprising dopants are provided. In one embodiment, a phosphorous-comprising dopant comprises a phosphorous source comprising a phosphorous-comprising salt, a phosphorous-comprising acid, phosphorous-comprising anions, or a combination thereof, an alkaline material, cations from an alkaline material, or a combination thereof, and a liquid medium.

Abstract: A semiconductor device includes: a first well and a second well formed in a substrate and having a different impurity doping concentration; a first isolation layer and a second isolation layer formed in the first well and the second well, respectively, and having a different depth; and a third isolation layer formed in a boundary region in which the first well and the second well are in contact with each other, and having a combination type of the first isolation layer and the second isolation layer.

Abstract: A doping mixture for coating semiconductor substrates which are then subjected to a high temperature treatment to form a doped layer includes at least one p- or n-dopant, water and a mixture of two or more surfactants. At least one of the surfactants is nonionic. Also, provided are a method for producing such a doping mixture and the use thereof.

Abstract: New photoresist are provided that comprises an Si-containing component and that are particularly useful for ion implant lithography applications. Photoresists of the invention can exhibit good adhesion to underlying inorganic surfaces such as SiON, silicon oxide, silicon nitride and other inorganic surfaces.

Abstract: Provided are methods of fabricating semiconductor chips, semiconductor chips formed by the methods, and chip-stack packages having the semiconductor chips. One embodiment specifies a method that includes patterning a scribe line region of a semiconductor substrate to form a semiconductor strut spaced apart from edges of a chip region of the semiconductor substrate.

Abstract: The present invention provides a method of forming a bipolar transistor. The method includes doping a silicon layer with a first type of dopant and performing a first implant process to implant dopant of a second type opposite the first type in the silicon layer. The implanted dopant has a first dopant profile in the silicon layer. The method also includes performing a second implant process to implant additional dopant of the second type in the silicon layer. The additional implanted dopant has a second dopant profile in the silicon layer different than the first dopant profile. The method further includes growing an insulating layer formed over the silicon layer by consuming a portion of the silicon layer and the first type of dopant.

Abstract: A method for producing a semiconductor component is proposed. The method includes providing a semiconductor body having a first surface; forming a mask on the first surface, wherein the mask has openings for defining respective positions of trenches; producing the trenches in the semiconductor body using the mask, wherein mesa structures remain between adjacent trenches; introducing a first dopant of a first conduction type using the mask into the bottoms of the trenches; carrying out a first thermal step; introducing a second dopant of a second conduction type, which is complementary to the first conduction type, at least into the bottoms of the trenches; and carrying out a second thermal step.

Abstract: SiC single crystal that includes a first dopant functioning as an acceptor, and a second dopant functioning as a donor is provided, where the content of the first dopant is no less than 5×1015 atoms/cm3, the content of the second dopant is no less than 5×1015 atoms/cm3, and the content of the first dopant is greater than the content of the second dopant. A manufacturing method for silicon carbide single crystal is provided with the steps of: fabricating a raw material by mixing a metal boride with a material that includes carbon and silicon; vaporizing the raw material; generating a mixed gas that includes carbon, silicon, boron and nitride; and growing silicon carbide single crystal that includes boron and nitrogen on a surface of a seed crystal substrate by re-crystallizing the mixed gas on the surface of the seed crystal substrate.

Abstract: Provided are organic n-doped electron transport layers comprising at least one electron transport material and at least one electron rich dopant material and organic p-doped hole transport layers comprising at least one hole transport material and at least one electron deficient dopant material.

Abstract: The method described herein enables the introduction of external impurities into Silicon Carbide (SiC) to be conducted at a temperature between 1150-1400° C. Advantages include: a) low temperature diffusion procedure with greater control of the doping process, b) prevent roughness of SiC surface, c) less surface defects and d) better device performance and higher yield. The method described herein involves depositing a ceramic layer that contains the desired impurity and a certain element such as oxygen (in the form of oxide), or other elements/compounds that draw out the silicon and carbon atoms from the surface region of the SiC leaving behind carbon and silicon vacancies which then allow the external impurity to diffuse into the SiC more easily. In another embodiment, the deposited layer also has carbon atoms that discourage carbon from escaping from the SiC, thus generating a surface region of excess carbon in addition to the silicon vacancies.

Abstract: A bidirectional transient voltage suppression device is disclosed. The bi-directional transient voltage suppression device comprises a semiconductor die. The semiconductor die has a multi-layer structure comprising a semiconductor substrate of a first conductivity type, a buried layer of a second conductivity type, an epitaxial layer, and five diffused regions. The buried layer and the semiconductor substrate form a first semiconductor junction. The first diffused region of the second conductivity type and the semiconductor substrate form a second semiconductor junction. The fourth diffused region of the first conductivity type and the third diffused region of the second conductivity type form a third semiconductor junction. The fifth diffused region of the first conductivity type and the second diffused region of the second conductivity type form a fourth semiconductor junction.

Abstract: An angled implantation process is used in implanting semiconductor fins of a semiconductor device and provides for covering some but not necessarily all of semiconductor fins of a first type with patterned photoresist, and implanting using an implant angle such that all semiconductor fins of a second type are implanted and none of the semiconductor fins of the first type, are implanted. A higher tilt or implant angle is achieved due to the reduced portions of patterned photoresist, that are used.

Abstract: A wafer includes a wafer frontside and a region adjacent to the device surface, wherein the region includes vacancy-oxygen complexes and the wafer frontside includes a predetermined surface structure to form thereon a device with a desired property.

Abstract: The gate tunnel leakage current is increased in the up-to-date process, so that it is necessary to reduce the gate tunnel leakage current in the LSI which is driven by a battery for use in a cellular phone and which needs to be in a standby mode at a low leakage current. In a semiconductor integrated circuit device, the ground source electrode lines of logic and memory circuits are kept at a ground potential in an active mode, and are kept at a voltage higher than the ground potential in an unselected standby mode. The gate tunnel leakage current can be reduced without destroying data.

Abstract: A process for production of a silicon ingot, by which a silicon ingot exhibiting a low resistivity even in the top portion can be produced. The process for the production of a silicon ingot comprises includes withdrawing a silicon seed crystal (13) from a silicon melt (11) to grow a silicon single crystal (12), with the silicon seed crystal (13) and the silicon melt (11) containing dopants of the same kind.

Abstract: Improved complementary doping methods are described herein. The complementary doping methods generally involve inducing a first and second chemical reaction in at least a first and second portion, respectively, of a dopant source, which has been disposed on a thin film of a semiconductor or semimetal material. The chemical reactions result in the introduction of an n-type dopant, a p-type dopant, or both from the dopant source to each of the first and second portions of the thin film of the semiconductor or semimetal. Ultimately, the methods produce at least one n-type and at least one p-type region in the thin film of the semiconductor or semimetal.

Abstract: A fast recovery diode includes an n-doped base layer having a cathode side and an anode side opposite the cathode side. A p-doped anode layer is arranged on the anode side. The anode layer has a doping profile and includes at least two sublayers. A first one of the sublayers has a first maximum doping concentration, which is between 2*1016 cm?3 and 2*1017 cm?3 and which is higher than the maximum doping concentration of any other sublayer. A last one of the sublayers has a last sublayer depth, which is larger than any other sublayer depth. The last sublayer depth is between 90 to 120 ?m. The doping profile of the anode layer declines such that a doping concentration in a range of 5*1014 cm?3 and 1*1015 cm?3 is reached between a first depth, which is at least 20 ?m, and a second depth, which is at maximum 50 ?m. Such a profile of the doping concentration is achieved by using aluminium diffused layers as the at least two sublayers.

Abstract: A method for epitaxially forming a first semiconductor structure attached to a second semiconductor structure is provided. Devices and methods described include advantages such as reduced lattice mismatch at an epitaxial interface between two different semiconductor materials. One advantageous application of such an interface includes an electrical-optical communication structure. Methods such as deposition of layers at an elevated temperature provide easy formation of semiconductor structures with a modified lattice constant that permits an improved epitaxial interface.

Abstract: Improved high quality gate dielectrics and methods of preparing such dielectrics are provided. Preferred dielectrics comprise a rare earth doped dielectric such as silicon dioxide or silicon oxynitride. In particular, cerium doped silicon dioxide shows an unexpectedly high charge-to-breakdown QBD, believed to be due to conversion of excess hot electron energy as photons, which reduces deleterious hot electron effects such as creation of traps or other damage. Rare earth doped dielectrics therefore have particular application as gate dielectrics or gate insulators for semiconductor devices such as floating gate MOSFETs, as used in as flash memories, which rely on electron injection and charge transfer and storage.

Abstract: A method for simultaneous recrystallisation and doping of semiconductor layers, in particular for the production of crystalline silicon thin layer solar cells. A substrate base layer 1 is produced, and subsequently, an intermediate layer system 2 which has at least one doped partial layer is deposited on the base layer. An absorber layer 3 which is undoped or likewise doped is deposited on the intermediate layer system 2, and in a recrystallisation step, the absorber layer 3 is heated, melted, cooled and tempered. Alternately, instead of an undoped capping layer, a capping layer system 4 which has at least one partial layer can also be applied on the absorber layer 3.

Abstract: A compound semiconductor substrate 10 according to the present invention is comprised of a Group III nitride and has a surface layer 12 containing a chloride of not less than 200×1010 atoms/cm2 and not more than 12000×1010 atoms/cm2 in terms of Cl and an oxide of not less than 3.0 at % and not more than 15.0 at % in terms of O, at a surface. The inventors conducted elaborate research and newly discovered that when the surface layer 12 at the surface of the compound semiconductor substrate 10 contained the chloride of not less than 200×1010 atoms/cm2 and not more than 12000×1010 atoms/cm2 in terms of Cl and the oxide of not less than 3.0 at % and not more than 15.0 at % in terms of O, Si was reduced at an interface between the compound semiconductor substrate 10 and an epitaxial layer 14 formed thereon and, as a result, the electric resistance at the interface was reduced.

Abstract: A mechanism for changing the doping profile of semiconductor devices over time using radioisotope dopants is disclosed. This mechanism can be used to activate or deactivate a device based on the change in doping profile over time. The disclosure contains several possible dopants for common semiconductor substrates and discusses several simple devices which could be used to actuate a circuit. The disclosure further discloses a means for determining the optimal doping profile to achieve a transition in bulk electrical properties of a semiconductor at a specific time.

Abstract: This invention concerns semiconductor devices of the general type comprising a counted number of dopant atoms (142) implanted in regions of a substrate (158) that are substantially intrinsic semiconductor. One or more doped surface regions (152) of the substrate (158) are metallized to form electrodes (150) and a counted number of dopant ions (142) are implanted in a region of the substantially intrinsic semiconductor.

Abstract: A method for improving the quality of a SiC layer by effectively reducing or eliminating the carrier trapping centers by high temperature annealing and a SiC semiconductor device fabricated by the method. The method for improving the quality of a SiC layer by eliminating or reducing some carrier trapping centers includes the steps of: (a) carrying out ion implantation of carbon atom interstitials (C), silicon atoms, hydrogen atoms, or helium atoms into a shallow surface layer (A) of the starting SiC crystal layer (E) to introduce excess carbon interstitials into the implanted surface layer, and (b) heating the layer for making the carbon interstitials (C) to diffuse out from the implanted surface layer (A) into a bulk layer (E) and for making the electrically active point defects in the bulk layer inactive. After the above steps, the surface layer (A) can be etched or mechanically removed. The SiC semiconductor device is fabricated by the method.

Abstract: An approach for providing a cleave initiation using a varying ion implant dose is described. In one embodiment, there is a method of forming a substrate. In this embodiment, a semiconductor material is provided and implanted with a spatially varying dose of one or more ion species. A handler substrate is attached to the implanted semiconductor material. A cleave of the implanted semiconductor material is initiated from the handler substrate at a preferential location that is a function of a dose gradient that develops from the spatially varying dose of one or more ion species implanted into the semiconductor material.

Abstract: A method of manufacturing a semiconductor device comprises the steps of, in sequence: depositing a first silicon layer; patterning the first silicon layer to obtain a first silicon region; implanting a first dopant into a first part of the first silicon region, the first part of the first silicon region defined using a first mask; depositing a second silicon layer; patterning the second silicon layer to obtain a second silicon region; and implanting a second dopant into a second part of the first silicon region, the second part of the first silicon region defined by the first mask and the second silicon region. A device comprises a semiconductor layer (6); a first doped region (5) within the semiconductor layer; a second doped region (7) within the first doped region (5); and a silicon layer (9) disposed over a part of the semiconductor layer; wherein the silicon layer is disposed over a part of the first doped region (5) but not over the second doped region (7).

Abstract: The present invention provides a photorefractive potassium niobate (KNbO3 ) crystal including a first impurity added substitutionally to the niobium (Nb) site and a second impurity added substitutionally to the potassium (K) site, wherein the first and second impurities are different. There is also provided a method of making the codoped potassium niobate crystal (KNbO3 ) of the present invention wherein the method includes adding at least one of the impurities to a melt composition during crystal growth, adding at least one of the impurities into an existing crystal using thermal diffusion, and/or adding at least one of impurities into an existing crystal using electrically assisted diffusion.

Abstract: In a p-type clad layer, not only a p-type dopant Zn but also Fe is doped. Its Zn concentration is 1.5×1018 cm?3 and the Fe concentration is 1.8×1017 cm?3. In a semi-insulating burying layer, Fe is doped as an impurity generating a deep acceptor level and the concentration thereof is 6.0×1016 cm?3. The Fe concentration in the p-type clad layer is thus three times higher than the Fe concentration in the burying layer.

Abstract: A method and device for reducing a dopant diffusion rate in a doped semiconductor region is provided. The methods and devices include selecting a plurality of dopant elements. Selection of a plurality of dopant elements includes selecting a first dopant element with a first atomic radius larger than a host matrix atomic radius and selecting a second dopant element with a second atomic radius smaller than a host matrix atomic radius. The methods and devices further include selecting amounts of each dopant element of the plurality of dopant elements wherein amounts and atomic radii of each of the plurality of dopant elements complement each other to reduce a host matrix lattice strain. The methods and devices further include introducing the plurality of dopant elements to a selected region of the host matrix and annealing the selected region of the host matrix.

Abstract: A method is disclosed for implanting and activating antimony as a dopant in a semiconductor substrate. A method is also disclosed for implanting and activating antimony to form a source/drain extension region in the formation of a transistor, in such a manner as to achieve high activation and avoid deactivation via subsequent exposure to high temperatures. This technique facilitates the formation of very thin source/drain regions that exhibit reduced sheet resistance while also suppressing short channel effects. Enhancements to these techniques are also suggested for more precise implantation of antimony to create a shallower source/drain extension, and to ensure formation of the source/drain extension region to underlap the gate. Also disclosed are transistors and other semiconductor components that include doped regions comprising activated antimony, such as those formed according to the disclosed methods.

Abstract: In an ion implantation method, a substrate is placed in a process zone and ions are implanted into a region of the substrate to form an ion implanted region. A porous capping layer is deposited on the ion implanted region. The substrate is annealed to volatize at least 80% of the porous capping layer overlying the ion implanted region during the annealing process. An intermediate product comprises a substrate, a plurality of ion implantation regions on the substrate, and a porous capping layer covering the ion implantation regions.

Abstract: A method for semiconductor processing is provided, wherein a removal of one or more layers is aided by structurally weakening the one or more layers via ion implantation. A semiconductor substrate is provided having one or more primary layers formed thereon, and a secondary layer is formed over the one or more primary layers. One or more ion species are implanted into the secondary layer, therein structurally weakening the secondary layer, and a patterned photoresist layer is formed over the secondary layer. Respective portions of the secondary layer and the one or more primary layers that are not covered by the patterned photoresist layer are removed, and the patterned photoresist layer is further removed. At least another portion of the secondary layer is removed, wherein the structural weakening of the secondary layer increases a removal rate of the at least another portion of the secondary layer.

Abstract: A method for manufacturing a semiconductor optical device includes forming a BDR (Band Discontinuity Reduction) layer of a first conductivity type doped with an impurity, depositing a contact layer of the first conductivity type in contact with the BDR layer after forming the the BDR layer, the contact layer being doped with the same impurity as the BDR layer and used to form an electrode, and heat treating after forming the contact layer.

Abstract: A method is provided capable of universally controlling the proximity gettering structure, the need for which can vary from manufacturer to manufacturer, by arbitrarily controlling an M-shaped distribution in a depth direction of a wafer BMD density after RTA in a nitrogen-containing atmosphere. The heat-treatment method is provided for forming a desired internal defect density distribution by controlling a nitrogen concentration distribution in a depth direction of the silicon wafer for heat-treatment, the method including heat-treating a predetermined silicon wafer used for manufacturing a silicon wafer having a denuded zone in the vicinity of the surface thereof.

Abstract: The disclosure provides a method for fabricating a semiconductor substrate comprising the steps of: providing a semiconductor on insulator type substrate, providing a diffusion barrier layer and providing a second semiconductor layer. By providing the diffusion barrier layer, it becomes possible to suppress diffusion from the highly doped first semiconductor layer into the second semiconductor layer. The invention also relates to a corresponding semiconductor substrate and opto-electronic devices comprising such a substrate.