DE102005029272A1 - Radiation-emitting semiconductor chip for data communications has electrical connection that is either laterally apart from injection section or overlaps injection and isolation sections - Google Patents

Abstract

The semiconductor body (2) is provided in the lateral main extending direction with a major surface (3) and semiconductor layers (4) having active zones (5). An electrical connection (6) is provided on the major surface that includes an injection section (7) and an isolation section (8). A charge is applied to the semiconductor body through the injection section that is connected to the electrical connection. The electrical connection either overlaps the injection and isolation sections or is laterally apart from the injection section.

Description

The The present invention relates to a radiation-emitting semiconductor chip with a semiconductor body, a lateral main extension direction, a main surface and a semiconductor layer sequence with a suitable for generating radiation has active zone.

Becomes such a semiconductor chip used for data transmission, so comes the modulation time of considerable importance. As modulation time is In this case, a time interval is considered in which in pulse mode of the Semiconductor chips, in particular with a predetermined current density or a predetermined current, the radiation power generated by the semiconductor chip starting from a predetermined initial value a predetermined End value reached. A modulation time can, for example, by given the rise time, the time it takes to be in the pulsed Operation of the semiconductor chip from the predetermined initial value of 10% of the radiation power that can be generated with the semiconductor chip, to reach the given end value of 90% of this maximum power.

The Modulation time is determined in particular by the lifetime of charge carriers in of the active zone, that is, the time that passes on average, until an electron in the active zone with a hole under radiation generation recombined. The lower the carrier lifetime in the active Zone is, the lower is usually the achievable modulation time.

In order to reduce the carrier lifetime in the active region and, accordingly, to increase the modulation time, the energized region of the active region, such as in the US 5,581,571 is deliberately reduced by forming a current diaphragm by means of oxidation of partial regions of the semiconductor body. The semiconductor body is energized on the entire surface by the main surface, the current diaphragm laterally constricting the current path in the semiconductor body such that only a partial region of the active zone is energized. As a result, the charge carrier density is increased in the active zone at a predetermined operating current density or predetermined operating current and thus reduces the carrier lifetime. However, the formation of such a current diaphragm is comparatively expensive and expensive.

A Object of the present invention is to provide a radiation-emitting Specify a semiconductor chip, which pulsed with a reduced modulation time operable and simplified and inexpensive to produce. Farther a semiconductor chip is to be specified, with which an increase of over the main area emitted radiation power is easily accessible. moreover It is an object of the invention, a simplified and inexpensive to carry out Specify a method for producing a semiconductor body for such a semiconductor chip.

In a method according to the invention for producing a semiconductor body for a radiation-emitting Semiconductor chip, wherein the semiconductor body has a lateral main extension direction, a main area and a semiconductor layer sequence having one for generating radiation has a suitable active zone, first becomes a radiation emission region the active zone, the area of the surface of the radiation emission area covered in the lateral direction area is smaller than the area the surface covered by the active zone in the lateral direction. Thereupon becomes the semiconductor layer sequence for the semiconductor body grown on a growth substrate, wherein the semiconductor layer sequence between the active zone and the main surface of the semiconductor body targeted grown with such a high resistance in the lateral direction is that at a charge carrier injection into the semiconductor body via a predetermined injection region of the main surface of the radiation generation in the active zone to the predetermined radiation emission range limited is.

The Accordingly, the semiconductor layer sequence can be grown in such a way that at a charge carrier injection in the semiconductor body over the Injection area of the main area the radiation generation in the active zone targeted to the radiation emission area limited is. The targeted energizing of a given subsection of the active zone, the radiation emission area, is thus facilitated. The carrier density in the active zone can subsequently in the operation of the semiconductor chip, without structural changes on the semiconductor body, especially on its crystal structure after growing, such as by forming a current shutter, can be increased in a simplified manner. In particular, can usually cost-intensive measures for modification of the crystal structure, such as oxidation or implantation, be waived.

short Modulation times can achieved so simplified and a fast modulable semiconductor chip with such a semiconductor body May be due to the abandonment of structural changes on the prefabricated semiconductor body inexpensive and be made simplified.

In a preferred embodiment is present the growth of the semiconductor layer sequence determines a suitable formation of the injection region, such that the product of the modulation time achievable during pulsed operation of the semiconductor chip and the radiation power coupled in the radiation emission region coupled out of the semiconductor body assumes a predetermined desired value. The semiconductor body or the semiconductor chip can thus be optimized for short modulation times, that is to say for high data rates, and a radiation power suitable for data transmission.

In In another preferred embodiment, the ratio of acreage of the injection area to the area which covered by the radiation emission region in the lateral direction area a predetermined setpoint less than 1 and preferably greater or equal to 0.5. The area which covered by the radiation emission region in the lateral direction area can therefore be greater than be the one of the injection area. The desired value is preferred greater than 0.8, more preferably greater than 0.9. The areas of the Injection range and the radiation emission range differ Thus, preferably with advantage due to the advantageous low current expansion in the semiconductor body in the lateral direction, which is due to the resistance in the semiconductor body in lateral direction is adjustable, only slightly.

In Another preferred embodiment is the radiation emission region chosen such that during operation of the semiconductor chip, a predetermined radiation power is decoupled from the semiconductor chip. The main surface is preferably the main outcoupling surface of Radiation from the semiconductor body intended. Advantageously, such a radiation power can be adjusted be that for data transfer is sufficient or particularly suitable. The larger the area of the radiation emission area is, the bigger, at the same operating current density, usually those generated in this or from the semiconductor body decoupled radiation power, but with correspondingly increased charge carrier lifetime and accordingly increased Modulation time.

In Another preferred embodiment is the radiation emission region chosen such that in pulsed operation of the semiconductor chip a predetermined modulation time is achieved or can be. Advantageously, the radiation emission area, especially its surface area, chosen so small such high carrier densities during operation of the semiconductor chip arise in the radiation emission range that in pulsed mode the predetermined modulation time can be achieved.

In In a further preferred embodiment, the semiconductor body has at least an expandable, in particular epitaxable, semiconductor layer on that between the active zone and the main surface, in particular the injection area, wherein the semiconductor layer is specifically grown so that the ratio of the area of the injection area to the area which covered by the radiation emission region in the lateral direction area bigger or is equal to a predetermined value. Preferably, the entire semiconductor body or the entire semiconductor layer sequence between the active zone and the main surface or the semiconductor body as a whole be formed in this way. The current expansion in the semiconductor body between the main surface and The active zone can thus be influenced such that in the semiconductor body between the active zone and the main surface targeted a small flow expansion takes place.

In a first embodiment comprises a radiation-emitting according to the invention Semiconductor chip a semiconductor body, a lateral main extension direction, a main surface and a Semiconductor layer sequence with a suitable for generating radiation active zone, and an electric field arranged on the main surface Connecting element, wherein the main surface is an injection area and having an isolation region, the injection region with the connecting element is electrically conductively connected, with respect to Insulation region and the injection area in the operation of the semiconductor chip only over the injection area charge carriers in the semiconductor body be injected and the connection element with the injection area and the isolation area overlaps or the connection element arranged laterally next to the injection area is.

During operation of the semiconductor chip, charge carriers can be injected into the semiconductor body by means of the connection element via the injection region of the main surface, by means of which radiation is generated in the active zone, in particular in the radiation emission region. Due to the overlap of the connection element with the isolation region and the injection region or the arrangement of the connection element laterally adjacent to the injection region, the generated radiation, in particular via the injection region, can emerge from the semiconductor chip from the main surface without the risk of significant absorption in the active zone generated radiation power is increased in the connection element. The connection element can therefore be designed to be optimized for an external connection connection, for example a wire bond, without having to take into account a radiation permeability of the connection element. The connecting element can be so simplified as the radiation generated in the active zone absorbing, such as metal-containing, be executed.

In a preferred embodiment, the area of the injection area is between 75 μm ² inclusive and 18000 μm ² inclusive. In particular, the injection area may have the area of a circle with a diameter between 10 μm and 150 μm, preferably between 60 μm and 100 μm. By dimensioning the injection area in such a way, a low modulation time suitable for data transmission at high data rates and at the same time a sufficiently high radiation power can be achieved.

In Another preferred embodiment is in the operation of the semiconductor chip in the radiation emission region of the active zone by means of charge carrier injection over the Injection area generates radiation and the ratio of area of the injection area to the area which covered by the radiation emission region in the lateral direction area assumes a specified setpoint less than 1. About the formation of the injection area and the semiconductor body, especially between the injection area and the active zone, can thus simplify the radiation emission region in the lateral direction, in particular by means of the configuration of the injection area defined which facilitates achieving low modulation times becomes. In particular, the radiation emission region can be restricted in a targeted manner become.

According to a further embodiment, a radiation-emitting semiconductor chip according to the invention comprises a semiconductor body which has a lateral main extension direction, a main surface and a semiconductor layer sequence with an active zone suitable for generating radiation, the main surface having an injection region and an isolation region, with respect to the isolation region and the injection region during operation of the Semiconductor chips are injected into the semiconductor body only via the injection region charge carriers in which the area of the injection area between 75 .mu.m ² and including 18000 .mu.m ² and / or during operation of the semiconductor chip in a radiation emission region of the active zone by means of charge carrier injection over the injection area radiation is generated and the ratio of the area of the injection area to the area of the radiation emission area in lat In the direction of the covered area, a predetermined setpoint value less than 1 is assumed.

through Such a semiconductor chip can be simplified for data transmission suitable low modulation time in conjunction with one for data transmission suitable, coupled out of the semiconductor chip radiation power will be realized.

In a preferred embodiment is on the main surface electrically connected to the injection area electrically connected Connection element arranged with the injection area and the Isolation area overlaps or laterally adjacent to the injection area.

In In another preferred embodiment, the connection element overlaps with the injection area and / or the isolation area only partially.

There below the isolation area - due to lack of carrier injection in this area and the favorable low current expansion - in the active zone essentially no radiation is generated is with Preference a majority the area of the connection element via arranged the isolation area. So can the absorption of radiation be reduced in the connection element. For example, an area fraction the total area of the connecting element of more than 50%, preferably more than 80%, more preferably more than 90%, be arranged over the isolation region.

In In another preferred embodiment, the area of the injection area is less than 50%, preferably less than 30%, more preferably less than 20% or less than 10% of the total area the main surface.

Prefers forms the remaining, not designed as an injection area Part of the main area the isolation area.

The Invention is based on the idea that a semiconductor body by means of a standard process made, for example by means of a Epitaxieprozesses is grown, wherein in the finished semiconductor chip targeted only a predetermined subregion of the active zone of the semiconductor body, the radiation emission region, is energized. As a result, the charge carrier lifetime in the radiation-generating Area of the active zone and consequently the achievable modulation time be reduced. The radiation emission area of the active zone is due in particular to the between the active zone and the main area specifically increased resistance of the semiconductor body in the lateral direction, essentially by the formation of the Injection area determined. At a limitation of the radiation emission range in the lateral direction after the production of the semiconductor body, approximately by means of a complex current diaphragm, for example by means of costly implantation or oxidation of the type mentioned could be trained can be dispensed with advantage.

In the context of the invention, the half lead Terkörper be made specifically so that the current expansion in the semiconductor body is kept as low as possible. This can be achieved by a targeted influencing of the resistance in the lateral direction in the production of the semiconductor body. In particular, within the scope of the invention, a thick semiconductor layer, which is often provided in conventional semiconductor chips, for example with a thickness of 1 μm to 3 μm, can be dispensed with for expanding the current, which essentially serves for the laterally full energization of the semiconductor body. Rather, an unusually low conductivity of at least one semiconductor layer is used to inject charge carriers from the injection region in a predefined and defined manner into the radiation emission region, wherein in particular the lateral extent of the radiation emission region is determined. Due to the omission of a conventional current spreading layer, the growth time in manufacturing the semiconductor body can be advantageously reduced, thereby reducing the manufacturing cost.

Of the Semiconductor body can continue to advantage by means of manufacturing processes that those of semiconductor bodies for conventional Semiconductor chips correspond to be manufactured, in contrast to usual Semiconductor chips, the current expansion deliberately kept low, preferably almost complete suppressed is. A current injection unlike traditional ones Semiconductor chips, where usually over substantially the entire main area charge carrier in the semiconductor body be injected, in the invention in the operation of the semiconductor chip preferably targeted only over a subarea of the main area, the injection area, instead.

manufacturing and assembly machines for such Semiconductor chips can in particular with regard to the lateral dimension of the semiconductor chip with opposite conventional semiconductor chips unchanged Parameters are operated. The semiconductor body, unlike usual Semiconductor chips targeted to a only partially energized the active zone in the radiation emission area for generating radiation be made towards. On modifications to the crystal structure of the Semiconductor body after manufacturing, especially growing up, to the effect that at full surface Charge carrier injection in the semiconductor body only one area of the active zone is energized, can be beneficial be waived.

Further can in the context of the invention to a targeted training of a Semiconductor body, whose active zone provided for substantially full-area energization is and one for a fast modulation suitable predetermined surface area has, for be dispensed with a fast-modulated semiconductor chip. at According to the invention, the active zone is preferably not full-surface, but only energized in a, in particular predetermined, partial area.

Process steps such as a mesa etch, the the full surface can define to be energized active zone are often costly. In particular, this is usually low for Modulation times needed to see comparatively small lateral extent of the active zone their training due to the small size of the production cost and the manufacturing costs increased. Will the active zone of a semiconductor body with such a small lateral dimension, e.g. 80 μm, entire area energized, so can continue the efficiency of radiation generation of the semiconductor chip due to non-radiative surface recombination be reduced at the mesaflanken.

Of the Semiconductor body for the Semiconductor chip can in the invention in a planar process, in particular without the etching a mesa, oxidation or implantation for lateral limitation of the radiation emission region

In a further preferred embodiment is the predetermined setpoint, the relationship of the area of the injection area to the surface which covered by the radiation emission region in the lateral direction area assumes greater than 0.5. This means that the current expansion between the main surface and the active zone is set so that of the total of the active area in the lateral direction covered area at most the double area of the injection area is energized. Achieving low modulation times is so relieved. Preferably, the desired value is greater than 0.8, more preferably it is greater than 0.9. This can be special low modulation times can be achieved.

In Another preferred embodiment is with the semiconductor chip a modulation time of 20 ns or less, preferably 15 ns or less, more preferably 10 ns or less. In particular, with the semiconductor chip a modulation time of 5 ns or less can be achieved. Such modulation times are for data transmission suitable for a high data rate.

In the context of the invention, a time interval is considered as the modulation time, during which the pulsed operation of the semiconductor chip, in particular with a predetermined current density or a predetermined current, reaches the radiation power generated by the semiconductor chip starting from a predetermined initial value. A modulation time, for example, by the Rise time to be given, the time that is required in the pulsed operation of the semiconductor chip, for example by means of a rectangular pulse, during a pulse duration of the predetermined initial value, such as a fraction of the maximum generated by the semiconductor chip radiation power, eg 10% of the maximum power to predetermined final value, eg 90% of the maximum power to arrive. The initial value is less than the final value at the rise time. The reverse is true for the fall time, the initial value preferably being greater than the end value. Instead of 10% and 90%, of course, other customary start and / or end values, such as 0% and 100%, can be set. The lower the modulation time, the higher the generally achievable data transmission rate.

In Another preferred embodiment covers the radiation emission region a vertical projection of the injection area on the active zone Completely. The injection area is therefore particularly above the Radiation emission region, wherein the radiation emission region the injection area completely covered in vertical projection. On costly measures for power supply in the semiconductor body, the current in the lateral direction to the radiation emission area directing, can be dispensed with.

In Another preferred embodiment is the injection area as simply connected Area of the main area executed. Over a Such formation of the injection area can be the generation of radiation on a coherent, in particular to a simply contiguous, radiation emission area be limited to the active zone. In this way, an efficient, concentrated in area Radiation generation can be facilitated.

In Another preferred embodiment is the isolation area and / or the injection area, in particular over the entire area, with the active zone in the vertical direction directly electrically conductive connected. In particular, the isolation area can therefore in vertical Direction directly conductive to be connected to the main surface. On additional activities for electrical insulation, in particular for current conduction in Semiconductor body, in terms of a vertical direct conductive connection of the isolation region the main surface to the active zone can be due to the only area-wise energization the main surface dispensed in the injection area. The isolation area is accordingly preferably not as an insulating area, but rather as formed by the connection element electrically insulated area.

In In a further preferred embodiment, the semiconductor body is in vertical direction between the injection area and / or the main area and the active zone free from a resistance of the semiconductor body in specifically increase the lateral direction Foreign element. A foreign element is considered to be an element that through structural changes, in particular on the crystal structure of the semiconductor body its production, in particular after the growth of the semiconductor layer sequence, is trained. For example, a foreign element could be using an implantation region or an oxidation region is formed be. Preferably, the entire semiconductor body is formed free of foreign elements.

With Advantage can be in the invention to such a modification of Crystal structure of the semiconductor body be dispensed with foreign elements. The manufacturing costs for one such semiconductor chip are due to the absence of such Foreign element advantageously reduced.

In Another preferred embodiment is between the main surface and the active zone at least one semiconductor layer, preferably a plurality of semiconductor layers, wherein the semiconductor layer or the plurality of semiconductor layers, in particular via their entire lateral extent, a resistance in lateral direction having 500 Ωsq or larger, in particular 1000 Ωsq or bigger, is. By means of a semiconductor layer which has such a high resistance in the lateral direction, the lateral confinement of the radiation emission region, in particular to achieve the predetermined setpoint, simplified respectively. Optionally, the semiconductor layer may also have a higher resistance in the lateral direction, up to about 4000 Ωsq. This will the lateral boundary of the radiation emission region or the achievement of a target value of the ratio of the area of the injection area to the area which covered by the radiation emission region in the lateral direction area close to 1 eased.

In Another preferred embodiment is the radiation emission region of side surfaces, the the semiconductor body bound in the lateral direction, laterally spaced. The danger Radiationless recombination of charge carriers in the area of the side surfaces of the active zone is by such a spaced arrangement of the radiation emission region reduced from the side surfaces. Achieving a high, generated in the radiation emission area Radiation power is thus facilitated.

In a further preferred embodiment, an electrically conductive injection element is arranged on the main surface, which, in particular directly, is electrically conductive with the connection element and connected to the injection area.

Prefers the injection element adjoins the semiconductor body, in particular directly, and the injection area is characterized by the, in particular immediate, Contact area between the semiconductor body and the injection element educated.

The Injection element may in particular with regard to the electrical Be performed optimized contact properties to the semiconductor body, whereas the connection element preferably has an external connection connection, about a wire bond, is particularly suitable.

In Another preferred embodiment is the connection element on the semiconductor body opposite Side of the injection element arranged. Preferably overlaps the connection element with the injection element, in particular only, partially. As a result, the charge carrier injection from the connection element via the Injection element can be simplified in the semiconductor body or done more efficiently.

In In another preferred embodiment, the connection element is especially overlapping, arranged laterally next to the injection element. This can be with Advantage reduces the vertical extent of the semiconductor chip become.

In a further preferred embodiment, an insulating layer is arranged or formed between the connection element and the insulation region, wherein the insulation layer electrically isolates the insulation region from the connection element. The insulating layer may contain, for example, a silicon nitride, such as SiN, a silicon oxide, such as SiO or SiO ₂ , a silicon oxynitride, such as SiON, or an aluminum oxide, such as Al ₂ O ₃ . The insulating layer may extend along the lateral flanks of the semiconductor body and thus preferably has a passivating and protective effect with respect to the semiconductor body, in particular the active zone, against harmful external influences, such as moisture.

Possibly the insulation layer can also be used as a barrier layer, such as a Schottky barrier be. For this purpose, the connection element is preferably directly on the Semiconductor body arranged, wherein between the connection element and the semiconductor body a Barrier forms, so that over the insulation region no charge carriers are injected into the semiconductor body.

In Another preferred embodiment is the injection element for the generated radiation permeable executed. In the radiation emission region, in particular below the injection element is disposed, generated radiation, the injection element on this way simplifies radiating and the semiconductor chip over the Leave injection element.

In In another preferred embodiment, the injection element contains a radiation-transparent, in particular electrically conductive, Material, such as a radiation-transmissive electrically conductive oxide. A radiolucent electrically conductive Oxide (TCO: Transparent Conducting Oxide) can, in addition to comparatively high radiation transmission over one wide wavelength range also high conductivities in the lateral direction. By means of such an injection element can the injection area, especially at a maximum partial overlap between the injection element and the connection element, simplified be energized laterally homogeneous.

Radiation-permeable electrically conductive oxides, in particular metal oxides, such as a zinc oxide, for example ZnO, a tin oxide, for example SnO or SnO ₂ , or an indium tin oxide, for example an ITO, are particularly suitable for this purpose. A zinc oxide is often characterized by particularly good electrical contact properties to p-type semiconductor materials, a tin oxide often by particularly good contact properties to n-type semiconductor materials. To increase the conductivity in the lateral direction, the injection element may be doped with, for example, aluminum or antimony. Aluminum is particularly suitable as a dopant for a zinc oxide, antimony as a dopant for a tin oxide.

The Injection element may have a resistance in the lateral direction of 100 Ωsq or less, in particular 50 Ωsq or less, in particular 25 Ωsq or less. The injection element preferably has one Resistance in the lateral direction on the smaller than that of the at least one semiconductor layer, due to its advantageous high resistance in the lateral direction, the lateral current expansion limited. Particularly preferred is the resistance in the lateral direction of the injection element is smaller than that of the semiconductor layers the semiconductor layer sequence between the active zone and the main surface are arranged or which form the semiconductor body. The ratio of Resistance in the lateral direction of the injection element to the the semiconductor layer (s) is preferably 0.1 or less, more preferably 0.05 or less, especially 0.025 or less.

In a further preferred embodiment, the injection element is designed as an antireflection element. Reflection losses due to reflection of radiation generated in the radiation emission region at the active zone facing side of the injection element can be reduced so. For this purpose, the injection element is preferably designed as a λ / 4 layer, in particular with a thickness of an integer, preferably odd, multiple of the quarter wavelength of the radiation generated in the semiconductor body in the medium of the injection element.

In a further preferred embodiment, the semiconductor body, in particular the semiconductor layer or a plurality of semiconductor layers of the semiconductor body, and / or the active zone contains a III-V semiconductor material, in particular a material from the III-V semiconductor material systems In _x Ga _y Al _{1 xy} P, In _x Ga _y Al _1-xy N or In _x Ga _y Al _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1. III-V semiconductor materials are disclosed efficient radiation generation, especially from the ultraviolet to the visible to the infrared spectral range, particularly suitable. Here, In _x Ga _y Al _1-xy N is particularly suitable for ultraviolet to green-yellow radiation, In _x Ga _y Al _1-xy P especially for yellow to red radiation and In _x Ga _y Al _1-xy As, especially for infrared radiation. Furthermore, by means of the material systems In _x Ga _y Al _1-xy N and In _x Ga _y Al _1-xy P, a semiconductor layer with advantageously high resistance in the lateral direction can be formed in a particularly simple manner. As for a semiconductor body, in particular for the lateral confinement of the radiation emission region, the material system In _x Ga _y Al _1-xy P has proven to be particularly suitable.

In Another preferred embodiment comprises the active zone a heterostructure, in particular a double heterostructure, or Single or multiple quantum well structure. By means of such structures, the radiation generation in the active zone, especially in the radiation emission area, especially done efficiently. Such executed active zones are for production a high radiation power in a radiation emission area a comparatively small surface area particularly suitable.

The Designation Quantum well structure includes in the context of the application any structure, in the case of carriers by confinement quantization their energy states Experienced. In particular, the term includes quantum well structure no information about the dimensionality the quantization. It thus includes u.a. Quantum wells, quantum wires and Quantum dots and any combination of these structures.

In Another preferred embodiment, the semiconductor chip a mirror layer, preferably on the opposite side of the main surface Side of the active zone is arranged. Conveniently, the mirror layer for in the radiation emission range The radiation generated in the active zone is reflective. On that way the over the main surface of the semiconductor body decoupled radiation component by reflection at the mirror layer elevated become.

The Mirror layer here, in particular monolithic, integrated in the semiconductor body and executed as a Bragg mirror be or on the semiconductor body be arranged. If the mirror layer is arranged on the semiconductor body so contains the mirror layer preferably comprises a metal, such as Au, Al, Ag, Pt, or an alloy with at least one of these materials. Prefers the mirror layer is made essentially metallic. Au characterized by advantageous high reflectivities in the red Spectral range off while Al and Ag also in blue to green Spectral range high reflectivities demonstrate. Across from one integrated in the semiconductor body Bragg mirror, whose reflectivity strong from the angle of incidence of the radiation on the mirror, the preferably formed by a plurality of semiconductor layers is, depends a metal-containing mirror layer has a low angle dependence the reflectivity on.

In Another preferred embodiment is the semiconductor chip as a thin-film semiconductor chip executed. Under a thin-film semiconductor chip In this case, a semiconductor chip is understood to be the semiconductor body a carrier is arranged, that of the growth substrate on which the semiconductor layer sequence the semiconductor body, in particular epitaxially, has grown different. The growth substrate can be detached in particular from the semiconductor body or the semiconductor chip can be carried out without waxing substrate be. Such an embodiment of the semiconductor chip is for a semiconductor chip with a metal-containing mirror layer particularly suitable. Preferably, the mirror layer between the carrier and the semiconductor body arranged, with particular preference between the mirror layer and the carrier a connection layer is arranged. By means of the bonding layer can the semiconductor body mechanically stable on the support be attached. The bonding layer can be used, for example, as a solder layer or as one formed by a wafer bonding method Layer be realized.

• – an einer zu einem Trägerelement, insbesondere dem Träger, hin gewandten Hauptfläche einer zur Strahlungserzeugung vorgesehenen Halbleiterschichtenfolge, insbesondere einer Epitaxieschichtenfolge, ist eine reflektierende Schicht, insbesondere eine Spiegelschicht, aufgebracht oder ausgebildet, die zumindest einen Teil der in der Halbleiterschichtenfolge erzeugten elektromagnetischen Strahlung in diese zurückreflektiert;
• – die Halbleiterschichtenfolge weist eine Dicke im Bereich von 20μm oder weniger, insbesondere im Bereich von 10 μm auf; und
• – die Halbleiterschichtenfolge enthält mindestens eine Halbleiterschicht mit zumindest einer Fläche, die eine Durchmischungsstruktur aufweist, die im Idealfall zu einer annähernd ergodischen Verteilung des Lichtes in der Halbleiterschichtenfolge führt, d.h. sie weist ein möglichst ergodisch stochastisches Streuverhalten auf.

A thin-film semiconductor chip may further be characterized by one or more of the following characteristics:

• On a main surface of a semiconductor layer sequence intended for generating radiation, in particular an epitaxial layer sequence, a reflective layer, in particular a mirror layer, is applied or formed on a support element, in particular the support, at least a part of the in the semiconductor layer sequence generated electromagnetic radiation reflected back into this;
• The semiconductor layer sequence has a thickness in the range of 20 μm or less, in particular in the range of 10 μm; and
• The semiconductor layer sequence contains at least one semiconductor layer with at least one surface which has a mixed-through structure which, in the ideal case, leads to an approximately ergodic distribution of the light in the semiconductor layer sequence, ie it has as ergodically stochastic scattering behavior as possible.

One Basic principle of a thin-film LED chip For example, see I. Schnitzer et al., Appl. Phys. Lett. 63 (16), 18 October 1993, 2174-2176 described, whose disclosure content insofar hereby by reference is recorded.

One Thin-film semiconductor chip is in good approximation a Lambert surface radiator.

In Another preferred embodiment is the semiconductor chip for generating incoherent radiation educated. The semiconductor chip can be used, for example, as an LED chip or RCLED chip (RCLED: Resonant Cavity Light Emitting Diode). Opposite one LED chip has a RCLED chip one, in particular internal, monolithic in the semiconductor body integrated, resonator on, preferably by means of two, in particular monolithic in the semiconductor body integrated, Bragg mirror is formed, between which the active zone is arranged. By means of a RCLED chip can be increased, amplified in direction the main surface directed radiation extraction from the semiconductor body achieved become.

In Another preferred embodiment is one of the semiconductor chip generated radiation for coupling into a light guide, such as a Polymer fiber (POF: polymer optical fiber), in particular for data transmission, intended. The light guide is preferably for an arrangement on the part of Main area especially over half the injection area provided.

In Another preferred embodiment is the inventive method in the wafer composite for the simultaneous production of a plurality of Semiconductor bodies or, in particular, inventive semiconductor chips feasible.

When Wafer composite is considered here a semiconductor layer structure arranged on a carrier layer, provided for forming a plurality of semiconductor bodies is. The carrier layer can in particular, the growth substrate of the semiconductor layer structure include or be different from this. The individual semiconductor bodies are structured with preference from the semiconductor layer structure of the composite. In particular, the method as a planar method, without mesa etching, implantation or oxidation be, with the preference to the semiconductor layer structure or on the structured semiconductor bodies no structural modifications, such as their crystal structure concerning become.

Prefers is the inventive method for producing a semiconductor body for a radiation-emitting according to the invention Semiconductor chip provided.

The here and in the following for Accordingly, the features described in the semiconductor chip can also be used for the method according to the invention be used and vice versa.

Further Features, advantageous embodiments and expediencies The invention will become apparent from the following description of the embodiments in conjunction with the figures.

It demonstrate:

1 a first embodiment of a semiconductor chip according to the invention with reference to a schematic plan view in FIG 1A and a schematic sectional view in FIG 1B .

2 A second embodiment of a radiation-emitting semiconductor chip according to the invention with reference to a schematic sectional view,

3 a schematic plan view of a third embodiment of a radiation-emitting semiconductor chip according to the invention,

4 based on schematic sectional views in the 4A and 4B two variants of semiconductor bodies for a radiation-emitting semiconductor chip according to the invention and

5 an embodiment of a method according to the invention with reference to in the 5A to 5E in intermediate views shown in schematic sectional views.

Same, similar and equally acting elements are in the figures with provided the same reference numerals. It should also be noted that the figures not to scale and faithfully made in size are. Individual elements of the figures may be exaggerated for clarity shown big be.

1 shows a first embodiment of a radiation-emitting semiconductor chip according to the invention by means of a schematic plan view in FIG 1A and a schematic sectional view in FIG 1B along the line AA 1A ,

The radiation-emitting semiconductor chip 1 comprises a semiconductor body 2 , the main lateral extension direction, a major surface 3 and a semiconductor layer sequence 4 with an active zone suitable for generating radiation 5 having. On the main surface is an electrical connection element 6 , such as a terminal metallization arranged. The main area 3 of the semiconductor body 2 has an injection area 7 and an isolation area 8th on. The injection area is with the connection element 6 electrically conductively connected, wherein with respect to the isolation region and the injection region in the operation of the semiconductor chip only over the injection region charge carriers are injected into the semiconductor body. The connection element 6 is with the injection area 7 in particular by means of an injection element 9 electrically connected, that on the main surface 3 is arranged. During operation of the semiconductor chip, charge carriers can enter the main surface via the connection element and the injection element 3 in the semiconductor body 2 be injected and get into the active zone for generating radiation.

The injection area 7 is through the contact area of the injection element 9 to the semiconductor body 2 educated. The not with the injection element 9 covered part of the main area 3 forms the isolation area 8th ,

The connection element 6 overlaps with the isolation area 8th and the injection area 7 , The connection element 6 preferably overlaps with the injection area and the isolation area only partially so that portions of the isolation area and the injection area are not separated from the terminal 6 be covered.

The injection element 9 is directly electrically conductive with the connection element 6 which is overlapped with the injection member and disposed on the semiconductor body opposite side of the injection member, and the injection region 7 connected. The connection element 6 is furthermore arranged laterally next to the injection element and extends in particular in the vertical direction along the edge of the injection element. As a result, the charge carrier injection via the connection element 6 in the injection element 9 available area can be increased with advantage simplified.

Between the connection element 6 and the isolation area 8th is an insulation layer 10 arranged, which electrically isolates the isolation region from a direct charge carrier injection into the semiconductor body via the isolation region. The insulating layer contains SiN, for example.

The semiconductor body 2 , in particular its active zone 5 , is in the lateral direction of side surfaces 11 bounded laterally. Preferably, the insulation layer extends 10 also in the region of the side surfaces, in the vertical direction along the semiconductor body, so that the semiconductor body, in particular the active zone, is protected in the area of the side surfaces by the insulating layer then acting as a protective layer. Optionally, the insulating layer can extend at least partially in the vertical direction except for the side of the injection element opposite the semiconductor body or be arranged on this side.

Furthermore, the semiconductor chip 1 a mirror layer 12 on that on the main surface 3 opposite side of the active zone 5 or of the semiconductor body 2 is arranged. The mirror layer contains, for example, a metal, such as gold and / or is arranged between the carrier and the semiconductor body. The mirror layer is designed to be reflective of the radiation that can be generated in the active zone, so that it radiates over the main surface 3 Advantageously, the radiation component coupled out of the semiconductor chip is advantageously increased. The semiconductor body 2 is on the part of the mirror layer over a connecting layer 13 on a carrier 14 attached.

The connection layer 13 is in particular between the carrier 14 and the mirror layer 12 arranged. For example, the connection layer is designed as a solder layer. By means of the bonding layer 13 the semiconductor body is preferably mechanically stable on the carrier stabilizing the semiconductor body 14 attached. The carrier 14 is preferably from the growth substrate on which the semiconductor layer sequence 4 of the semiconductor body 2 , in particular epitaxial, grown, different. Accordingly, the semiconductor chip 1 preferably designed as a thin-film chip with detached growth substrate.

The carrier 14 is further preferably formed electrically conductive. For example, the carrier contains a suitable, in particular suitably doped, semiconductor material, for example GaAs. On the the semiconductor body 2 opposite side of the carrier is a mating connection element 15 , such as a Gegenanschlussmetallisierung arranged. The mating connection element 15 is about the carrier 14 , the connecting layer 13 and the mirror layer 12 , which are each in particular electrically conductive, electrically conductive with the active zone 5 connected.

The semiconductor chip 1 can be used to generate radiation via the connecting element 6 and the mating terminal element 15 be contacted electrically. The electrical connection element 6 is preferably provided for a wire bond and the mating connection element is preferably provided for a solder connection to an external connection means.

The active zone 5 is preferably designed for efficient radiation generation as a multiple quantum well structure or a double heterostructure. Furthermore, the active zone is preferably based on the III-V material system In _x Ga _y Al _1-xy P with 0 ≦ x ≦ 1, 0 ≦ y ≦ 1 and x + y ≦ 1, in which radiation in the red spectral region generates particularly efficiently can be. For example, the active zone is formed by means of InGaP, in particular In _0.5 Ga _0.5 P.

The active zone is preferably between two cladding layers, in particular of different conductivity type, which are the semiconductor layer sequence 4 may have, arranged and / or limited. For example, the cladding layers are based on the material system In _x Ga _y Al _1-xy P.

For an In _x Ga _y Al _1-xy -based semiconductor layer sequence 4 is particularly suitable as a growth substrate GaAs. For good lattice matching to a GaAs substrate, the layers of the semiconductor layer sequence based on In _x Ga _y Al _1-xy P are expediently formed from the sub-material system In _0.5 (Ga _y Al _1-y ) _0.5 P. Layers with 0≤y≤0.33 are particularly suitable for cladding layers.

The semiconductor chip 1 is preferably designed to generate incoherent radiation, such as an LED chip.

In operation of the semiconductor chip 1 be by means of the connection element 6 and the injection element 9 over the injection area 7 and of the main surface 3 opposite side of the active zone 5 by means of the mating connection element 15 Charge carriers - electrons or holes - injected into the semiconductor body. These can be in the active zone 5 recombine under radiation generation. About the injection area 7 In the semiconductor body injected charge carriers extend in the semiconductor body 2 in the direction of the active zone, wherein the energized region of the semiconductor body widening with increasing verticality from the injection region due to the current spreading in the lateral direction. By means of the mating connection element are on the main surface 3 opposite side of the semiconductor body 2 preferably full-surface charge carriers injected into the semiconductor body.

The course of the current from the injection area 7 or from the opposite side of the injection area of the semiconductor body 2 to the active zone 5 is by the dashed lines marked with arrows in 1B clarified and limited in particular by these lines. About the injection area 7 and the main surface 3 The opposite side of the semiconductor body in these, for example, with a current of 20 mA injected carriers can in a radiation emission region 16 , which is determined by the current spreading in the lateral direction between the injection region and the active zone, recombine with radiation generation.

In the radiation emission range 16 generated radiation 17 can be direct or under reflection at the mirror layer 12 from the semiconductor chip 1 or the semiconductor body 2 couple out. The injection element is preferred 9 this radiation-permeable executed and is of the radiation 17 irradiated.

Particularly suitable is a TCO material, such as ZnO: Al, for the injection element. Such a material is characterized by high conductivity in the lateral direction with high radiation permeability. The high conductivity ensures a laterally homogeneous charge carrier injection into the semiconductor body via the injection region 7 with a comparatively small contact surface between the connection element 6 and the injection element 9 , Absorption of radiation generated in the radiation emission region in the connecting element is thus largely avoided. The injection element may, for example, have a resistance in the lateral direction of 25 Ωsq and / or a thickness of 500 nm or less, preferably 300 nm or less, approximately 200 nm. With preference, the thickness of the injection element is chosen so large that a homogeneous Stromeinprägung over the injection area is achieved. Optionally, the injection element, in particular layer-like, as an anti-reflection element having a thickness of an odd multiple of the quarter wavelength of the radiation 17 be executed.

As in 1A is shown, the connection element circulates around the injection element in the contact area with the injection element, wherein the ring 11 has an interruption. One over the isolation area 8th arranged subarea 18 of the connection element 6 is preferably provided for connection to an external connection means, such as a bonding wire.

The semiconductor body 2 is further specifically designed such that in a charge carrier injection via an injection area 7 a preference In addition, a radiation emission region of a surface area determined before the production of the semiconductor body is formed. This is between the main surface 3 and the active zone 5 a semiconductor layer 19 or a plurality of semiconductor layers arranged having such a high resistance in the lateral direction that the current expansion between the main surface and the active zone is selectively suppressed. As a result, during operation of the semiconductor chip, the previously defined radiation emission region is energized. The area of the injection area is in particular smaller than that of the radiation emission area.

The semiconductor layer 19 has, for example, a resistance of 500 Ωsq or more, preferably of 1000 Ωsq or more. The semiconductor layer contains, for example, InAlP, in particular In _0.5 Al _0.5 P. The resistance in the lateral direction can furthermore be specifically increased by a dopant concentration of the semiconductor layer 19 is deliberately reduced. Care must be taken here that the conductivity in the semiconductor body in the vertical direction and thus the current supply to the active zone is not significantly impaired.

For p-doping of the semiconductor layer 19 is for example Mg or Zn, for n-doping of the semiconductor layer 19 Si or Te particularly suitable. For a p-doped semiconductor layer 19 is a dopant concentration of 1 × 10 ¹⁹ cm ^-3 or less and for an n-type semiconductor layer 19 a dopant concentration of 5 × 10 ¹⁷ cm ^-3 or less is particularly suitable. A p-doped InAlP layer has a particularly advantageous low conductivity in the lateral direction. Optionally, a jacket layer facing the main surface can also be designed as an InAlP layer with a low transverse conductivity.

The jacket layer facing the injection region is preferably designed with a high resistance in the lateral direction. For this purpose, for example, an InAlP, in particular In _0.5 Al _0.5 P, cladding layer is particularly suitable.

The semiconductor layer 19 For example, the plurality of semiconductor layers may have a thickness, in particular a total thickness, of 1000 nm or less, preferably 500 nm or less.

The injection area 7 is preferably formed as a single continuous area of the main surface. As a result, concentrated radiation generation in a simply connected area as a radiation emission area can be simplified. For example, the injection area is circular with a diameter of 80 microns. The radiation emission region can then also be formed in a circle with an enlarged diameter, for example of 84 μm, due to the specifically set, in particular selectively reduced, lateral current expansion. The radiation emission region is preferably widened laterally by 4 μm or less, particularly preferably by 3 μm or less, in relation to the injection region.

Of the Semiconductor body is thus deliberately made so that the current expansion as possible is kept low. In particular, a predefined one can be simplified in this way Setpoint of the ratio of the area of the injection area to the surface of the radiation emission region smaller than one can be realized. With the above values, such a relationship arises 0.91.

Furthermore, the radiation emission area 16 lateral to the side surfaces 11 spaced so that the risk of non-radiative recombination of charge carriers in the area of the side surfaces is reduced.

In pulsed operation of the semiconductor chip, particularly small modulation times can be achieved due to the targeted lateral confinement of the radiation emission region of the active zone. For example, a modulation time of 3 ns can be achieved in a simplified manner in this way. On the part of the main surface 3 from the semiconductor body 2 or the semiconductor chip 1 passing radiation can be coupled into a light guide, such as a polymer fiber, for data transmission.

The lateral boundary of the radiation emission area 16 can take place in such a semiconductor chip in particular without structural change to the crystal structure of the semiconductor body. In particular, the active zone in the vertical direction over the entire surface with the main surface 3 be electrically conductive, wherein due to the appropriate design of the contact structure by means of the connecting element 6 and the injection element 9 targeted only a portion of the active zone, the radiation emission area 16 , is energized.

In the production of the semiconductor body for the semiconductor chip, first of all a radiation emission region of the active zone is defined whose surface area is smaller than that of the active zone. Subsequently, the semiconductor layer sequence for the semiconductor body on a growth substrate, in particular between the active zone and the main surface of the semiconductor body, specifically grown with such a high resistance in the lateral direction that at a charge carrier injection into the semiconductor body over a predetermined injection area of the main surface, in particular one Area smaller than that of the radiation emission area, the generation of radiation in the active area is restricted to the predetermined radiation emission area. In this case, the injection region and / or the radiation emission region can be determined in such a way that the product of the modulation time and the radiation power generated in the radiation emission region or the radiation power coupled out of the semiconductor chip assumes a predetermined desired value during pulsed operation of the semiconductor chip. As a result, a small modulation time is enabled at the same time due to the given radiation power secure data transmission.

To form the electrical contact between the injection element 9 and the active zone 5 can be a contact layer 20 be provided in the semiconductor body. The injection element preferably borders 9 directly to the contact layer 20 at. The contact layer 20 can the semiconductor body 2 from the main area 3 limit. For the electrical contact with a zinc oxide-containing injection element, a p-type contact layer, in particular made of AlGaAs, is particularly suitable. If the semiconductor body contains a layer of the material system Al _x Ga _1-x As, where 0 ≦ x ≦ 1, and another layer of the material system In _x Ga _y Al _1-xy P, then the further layer is preferably made of the material system In _0.5 (Ga _y Al _1-y ) _0.5 P, with 0 ≦ y ≦ 1. A layer of the Al _x Ga _1-x As material system can be monolithically integrated into a semiconductor body based on the In _0.5 (Ga _y Al _1-y ) _0.5 P material system in a simplified manner.

Since a layer suitable for electrical contact formation often has a comparatively high conductivity in the lateral direction, which is undesirable for a semiconductor chip according to the invention owing to the elusive current expansion, the contact layer is 20 expediently made comparatively thin, so that it does not contribute significantly to the flow expansion. For example, the contact layer has a thickness of 100 nm or less, more preferably 50 nm or less. A thickness of 20 nm or more is particularly advantageous in view of good electrical contact properties of the contact layer.

The injection area preferably takes 7 20% or less, preferably 10% or less of the entire major surface.

This is at a substantially square in plan view substantially formed semiconductor chip with an edge length of 250 microns and a circular injection area of 80 microns in diameter, the semiconductor chip 1 for example, the case.

In 2 is a second embodiment of a radiation-emitting semiconductor chip according to the invention schematically illustrated by a sectional view.

Essentially, the in 2 illustrated semiconductor chip 1 the in 1 . shown In contrast to this is the connection element 6 lateral next to and to the injection element 9 arranged adjacent. In particular, the injection element and the connection element are arranged such that they do not overlap. In this way, the vertical extent of the semiconductor chip can be reduced. Compared with the semiconductor chip 1 However, the contact area between the connection element and the injection element is reduced.

3 shows a schematic plan view of a third embodiment of a semiconductor chip according to the invention 1 , Essentially, the supervision corresponds to 3 the in 1A . shown In contrast, the overlap area between the connection element 6 and the injection element 9 not ring-like executed. The overlap is rather formed by means of an approximately point-like overlap. The absorption of radiation generated in the radiation emission region in the connection element can thus be reduced.

4 shows by means of schematic sectional views in the 4A and 4B two variants of semiconductor bodies for a semiconductor chip according to the invention. In 4 are just the ones on the carrier 14 arranged semiconductor body 2 of the semiconductor chip shown. The remaining elements may be implemented according to the previously described embodiments.

Unlike the sectional view in 1B has the semiconductor body 2 in the variant according to 4A a monolithic Bragg mirror integrated in the semiconductor body 21 on. Since such a Bragg mirror, in contrast to a metallic mirror layer, monolithically integrated in the semiconductor body, the carrier 14 the growth substrate of the semiconductor layer sequence 4 of the semiconductor body 2 include or be formed from this.

In the variant according to 4B is the semiconductor body 2 for an RCLED chip. The active zone 5 is here arranged within a resonator, by means of the monolithically integrated in the semiconductor body Bragg mirror 21 and another Bragg mirror 22 , which is also monolithically integrated in the semiconductor body is formed. Also in this variant, the carrier 14 comprise the growth substrate or be formed from this.

5 shows an embodiment of a method according to the invention with reference to in the 5A to 5E in intermediate views shown in schematic sectional views.

In 5 is a method for producing a radiation-emitting semiconductor chip having a semiconductor body, which has a lateral main direction of extension, a main surface and a semiconductor layer sequence with a suitable radiation generating active zone.

In particular shows 5 a method for the simultaneous production of a plurality of semiconductor chips in the wafer composite. The semiconductor chips produced by means of this method essentially correspond to those in the exemplary embodiment 1 shown semiconductor chip.

First, a suitable lateral extent of the semiconductor body is determined. Preferably, this extent corresponds to that of semiconductor bodies for conventional semiconductor chips, approximately 250 × 250 μm ² , so that the relevant parameters of the production and / or placement machines need not be changed. Then, a partial region of the active region of the semiconductor body is set as the radiation emission region. In this case, the radiation emission region is preferably determined such that during operation of the semiconductor chip in the radiation emission region a predetermined radiation power is generated or a predetermined radiation power generated in the radiation emission region can be coupled out of the semiconductor chip. Furthermore, the radiation emission region is preferably determined such that a predetermined modulation time can be achieved during operation of the semiconductor chip.

below, 5A , becomes a semiconductor layer structure 400 on a growth substrate 230 , preferably epitaxially grown, wherein the semiconductor layer structure 400 between a main surface 300 and an active zone suitable for generating radiation 500 the semiconductor layer structure 400 is selectively grown with such a high resistance in the lateral direction, that in a charge carrier injection over a predetermined injection area of the main surface, the radiation generation in the active zone is limited to the previously defined radiation emission range.

For efficient radiation generation, especially in the red spectral region, an active zone based on the III-V semiconductor material system In _x Ga _y Al _1-xy P is particularly suitable. By forming the active zone as a double heterostructure or multiple quantum well structure, the internal quantum efficiency in the radiation generation in the radiation emission region can advantageously be increased in a simplified manner. As the growth substrate, a GaAs or Ge substrate is particularly suitable for a semiconductor layer structure substantially based on In _x Ga _y Al _1-xy P and / or Al _x Ga _1-x As.

On the part of the main surface 300 can be a contact layer 200 monolithic in the semiconductor layer structure 400 be integrated, which facilitates the formation of an electrical contact advantageously between the semiconductor material and an injection element to be arranged in the further process on the part of the main surface. If the injection element is made of ZnO, in particular of ZnO: Al, then an, in particular p-conducting, AlGaAs contact layer is particularly suitable for forming an ohmic contact. In this case, a contact with a substantially linear current-voltage characteristic is considered to be an ohmic contact in particular. The contact layer is designed to substantially suppress current spreading in the contact layer, preferably with a thickness of 100 nm, for example.

The semiconductor layer structure has one between the contact layer 2 and the active zone 500 an arranged semiconductor layer 190 or a plurality of semiconductor layers having a resistance in the lateral direction of 500 Ωsq or more, more preferably 1000 Ωsq or more. By way of example, the semiconductor layer contains InAlP and / or is 500 nm thick.

then, 5B , becomes the main surface 300 opposite side, in particular the growth substrate 230 opposite side, the semiconductor layer structure 400 a mirror layer 120 applied. The mirror layer can be made metallic and contains, for example, Au. For applying the mirror layer, a vapor deposition or sputtering process is particularly suitable.

On the part of the mirror layer 120 the composite is subsequently connected by means of a bonding layer 130 on a carrier layer 140 that from the growth substrate 230 the semiconductor layer structure 400 different, attached, 5C , The carrier layer may contain, for example, GaAs. The carrier layer is advantageously not subject to the comparatively high requirements of a growth substrate and can be chosen comparatively freely, for example with regard to high thermal conductivity, compared with the growth substrate. The connection layer 130 can be formed for example as a solder layer. After arranging the semiconductor layer structure on the carrier layer 140 the growth substrate is detached from the semiconductor layer structure, for example by means of an etching or a laser separation method.

On the main surface 300 on the part of that Growth substrate of the semiconductor layer structure 400 is detached, is subsequently a plurality of injection elements 9 disposed 5D , In this case, preference is given to each subarea of the semiconductor layer structure provided for forming a semiconductor body 400 arranged at least one injection element. In the mechanical contact region of the respective injection element 9 the semiconductor material becomes an injection area 7 formed, which is provided for the charge carrier injection into the semiconductor material.

The injection element contains, for example, a radiation-transmissive conductive metal oxide, such as ZnO. To form an ohmic contact with the semiconductor material is a p-type AlGaAs contact layer 200 particularly suitable. The injection elements 9 For example, sputtering may be applied to the semiconductor layer structure. Furthermore, the injection elements can be applied in a structured manner, for example by using a suitable mask, in particular a photoresist mask, or after complete application of an injection element layer to the wafer composite by means of appropriate structuring of the injection element layer, for example via an etching process.

Subsequently, the wafer composite is structured such that a plurality of side by side on the carrier layer 140 arranged semiconductor bodies 2 is trained 5E , For example, an etching method in combination with a suitably designed mask is suitable for this purpose. The semiconductor body 2 are preferred by gaps 25 spatially spaced from each other. In contrast to the formation of a semiconductor body, such as by Mesaätzung with such a lateral dimension that at full-area energization of the active zone, which would thus form the radiation emission area in their entirety, a small modulation time is achieved in the invention, due to the only partial energization of the active zone in a radiation emission area spaced from the side surfaces, losses due to radiationless surface recombination are kept low. Furthermore, complicated structural changes in the semiconductor material, such as by implantation or oxidation, can be dispensed with.

Thereupon, an insulating layer is formed from the side opposite the carrier layer 10 , in particular full surface, applied to the composite. The insulating layer contains SiN, for example. The insulation layer can be applied to the composite by sputtering or PECVD (Plasma Enhanced Chemical Vapor Deposition). Will the insulation layer 10 Applied over the entire surface of the composite, the material of the insulating layer of the injection elements 9 expediently removed again so that it can be electrically contacted in a later method step. The insulation layer 10 preferably extends on the side surfaces 11 that the semiconductor bodies 2 limit laterally, along. This will protect the active zones 5 the semiconductor body 2 elevated.

The following are electrical connection elements 6 applied to the composite. Preferably, each injection element is associated with at least one connection element and a connection element with its associated injection element 9 electrically connected. The connection elements are, for example, metallic, for example containing Au, designed and can be applied by vapor deposition on the composite. Of the areas of the main surfaces not covered with the injection elements and covered by the connection elements 3 the semiconductor body 2 the connection elements are over the subregions of the insulation layer arranged between the connection elements and the semiconductor material of the semiconductor bodies 10 electrically isolated.

On the semiconductor bodies 3 or the semiconductor layer structure 400 opposite side of the carrier layer 140 can, for example by means of vapor deposition, a counterconnection layer 150 , For example, a metallic layer can be applied, which is electrically connected to the active zone.

Along the lines 26 The composite can then, for example by means of sawing, into individual semiconductor chips 1 , according to the semiconductor chip 1 to be isolated. The mating connection element 15 out 1 can singulate from the counterconnection layer 150 emerge.

The Semiconductor chips can with one over the Formation of the injection area, in particular the embodiment of the injection element, certain, laterally limited radiation emission region, in a planar process and inexpensive without modifications to the Semiconductor material of the semiconductor body made after growing become. Compared with conventional Semiconductor chips is in the process described above, only the Injection element as additional Element formed the contact structure of the semiconductor chip. This can by a conventional compared to the production additional fast maskable semiconductor chips or additional masking or Structuring step can be achieved, taking on cost-intensive structural modifications to the semiconductor material are dispensed with can.

It should be noted that, of course, the invention does not only refer to semiconductor chips on In _x Ga _y Al _1-xy P and / or Al _x Ga _1-x As base. The Rather, the invention can also be applied to semiconductor chips based on other material systems, for example semiconductor chips of In _x Ga _y Al _{1 -xy} N-base.

The The invention is not by the description based on the embodiments limited. Much more For example, the invention includes every novel feature as well as every combination of features, in particular any combination of features in the claims includes, even if this feature or this combination itself not explicitly stated in the patent claims or exemplary embodiments is.

Claims (31)

Radiation-emitting semiconductor chip ( 1 ) comprising - a semiconductor body ( 2 ), which has a main lateral extension direction, a main surface ( 3 ) and a semiconductor layer sequence ( 4 ) with an active zone suitable for generating radiation ( 5 ), and - an electrical connection element arranged on the main surface ( 6 ), wherein - the main area has an injection area ( 7 ) and an isolation area ( 8th ), - the injection region is electrically conductively connected to the connection element, - are injected into the semiconductor body with respect to the insulation region and the injection region during operation of the semiconductor chip only via the injection region charge carriers and - the connection element overlaps with the injection region and the isolation region or the connection element laterally is arranged next to the injection area. Radiation-emitting semiconductor chip according to claim 1, characterized in that the area of the injection area ( 7 ) is between 75 μm ² inclusive and 18000 μm ² inclusive. Radiation-emitting semiconductor chip according to claim 1 or 2, characterized in that during operation of the semiconductor chip ( 1 ) in a radiation emission region ( 16 ) of the active zone ( 5 ) by means of charge carrier injection over the injection area ( 7 ) Radiation is generated and the ratio of the surface area of the injection area to the area of the area covered by the radiation emission area in the lateral direction assumes a predetermined desired value smaller than 1. Radiation-emitting semiconductor chip ( 1 ) comprising - a semiconductor body ( 2 ), which has a main lateral extension direction, a main surface ( 3 ) and a semiconductor layer sequence ( 4 ) with an active zone suitable for generating radiation ( 5 ), wherein - the main surface has an injection area ( 7 ) and an isolation area ( 8th ), are injected into the semiconductor body only with respect to the insulation region and the injection region during operation of the semiconductor chip via the injection region, in which the surface area of the injection region is between 75 μm ² and including 18000 μm ² , and / or Operation of the semiconductor chip in a radiation emission region ( 16 ) of the active zone is generated by means of charge carrier injection via the injection area radiation and the ratio of the surface area of the injection area to the area of the area covered by the radiation emission area in the lateral direction assumes a predetermined desired value smaller than 1. Radiation-emitting semiconductor chip according to claim 4, characterized in that on the main surface one with the injection area ( 7 ) electrically connected electrical connection element ( 6 ) is arranged and the connection element with the injection area and the isolation area ( 8th ) overlaps or the connection element is arranged laterally next to the injection area. Radiation-emitting semiconductor chip after at least one of the claims 3 to 5, characterized in that the desired value is greater than Is 0.5. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the injection region ( 7 ) as a simply connected area of the main area ( 3 ) is executed. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the isolation region ( 8th ) and / or the injection area ( 7 ), in particular over the whole area, with the active zone ( 5 ) is electrically connected directly in the vertical direction. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the semiconductor body ( 2 ) in the vertical direction between the injection area ( 7 ) and / or the main surface ( 3 ) and the active zone ( 5 ) is free of a foreign element that selectively increases the resistance of the semiconductor body in the lateral direction. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that between the main surface ( 3 ) and the active zone ( 5 ) at least one semiconductor layer ( 19 ) is arranged and the semiconductor layer, in particular over its entire lateral Extension, has a resistance in the lateral direction, which is 500 Ωsq or greater, in particular 1000 Ωsq or greater. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the radiation emission region ( 16 ) of side surfaces ( 11 ), the semiconductor body ( 2 ) in the lateral direction, laterally spaced. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that on the main surface ( 3 ) an electrically conductive injection element ( 9 ) is arranged, which, in particular directly, electrically conductively connected to the connection element ( 6 ) and the injection area ( 7 ) connected is. Radiation-emitting semiconductor chip according to claim 12, characterized in that the injection element ( 9 ) to the semiconductor body ( 2 ) and the injection area ( 7 ) is formed by the contact region between the semiconductor body and the injection element. Radiation-emitting semiconductor chip according to claim 12 or 13, characterized in that the connecting element ( 6 ) on the semiconductor body ( 2 ) opposite side of the injection element ( 9 ) is arranged. Radiation-emitting semiconductor chip according to one of Claims 12 to 14, characterized in that the connection element ( 6 ) with the injection element ( 9 ) partially overlapped. Radiation-emitting semiconductor chip according to one of Claims 12 to 15, characterized in that the connection element ( 6 ) laterally next to the injection element ( 9 ) is arranged. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that between the connection element ( 6 ) and the isolation area ( 8th ) an insulation layer ( 10 ) is arranged or formed, which electrically isolates the insulation region from the connection element. Radiation-emitting semiconductor chip according to one of Claims 12 to 17, characterized in that the injection element ( 9 ) is made permeable to the generated radiation. Radiation-emitting semiconductor chip according to one of Claims 12 to 18, characterized in that the injection element ( 9 ) contains a radiation-transmissive electrically conductive oxide. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the semiconductor body ( 2 ), in particular the semiconductor layer ( 19 ), and / or the active zone ( 5 ) a III-V semiconductor material, in particular a material of the III-V semiconductor material systems In _x Ga _y Al _1-xy P, In _x Ga _y Al _1-xy N or In _x Ga _y Al _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the semiconductor chip ( 1 ) a mirror layer ( 12 ) and the mirror layer on the main surface ( 3 ) opposite side of the active zone ( 5 ) is arranged. Radiation-emitting semiconductor chip after at least one of the preceding claims, characterized characterized in that the semiconductor chip is provided for pulsed operation is. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that the semiconductor chip ( 1 ) for generating incoherent radiation ( 17 ) is trained. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that one of the semiconductor chip ( 1 ) generated radiation ( 17 ) is provided for coupling into an optical waveguide, in particular for data transmission. Radiation-emitting semiconductor chip according to at least one of the preceding claims, characterized in that with the semiconductor chip ( 1 ) a modulation time of 20 ns or less, in particular 10 ns or less or 5 ns or less, is achievable. Method for producing a semiconductor body ( 2 ) for a radiation-emitting semiconductor chip ( 1 ), wherein the semiconductor body has a lateral main extension direction, a main surface ( 3 ) and a semiconductor layer sequence ( 4 ) with an active zone suitable for generating radiation ( 5 ), characterized by the steps, a) determining a radiation emission region ( 16 ) of the active zone, the surface area of the area covered by the radiation emission area in the lateral direction being smaller than the area of the area covered by the active zone in the lateral direction, b) growing the semiconductor layer sequence for the semiconductor body on a growth substrate ( 230 ), wherein the semiconductor layer sequence between the active zone and the main surface of the semiconductor body targeted with such a high resistance in lateral Is grown in a carrier injection into the semiconductor body over a predetermined injection area ( 7 ) of the main area, the generation of radiation in the active zone is restricted to the predetermined radiation emission area. A method according to claim 26, characterized in that prior to step b) a suitable formation of the injection area ( 7 ) is determined such that the product of the pulsed operation of the semiconductor chip ( 1 ) achievable modulation time and from the semiconductor body ( 2 ), in the radiation emission range ( 16 ) radiation power assumes a predetermined setpoint. Method according to claim 26 or 27, characterized in that the radiation emission region ( 16 ) is selected such that during operation of the semiconductor chip ( 1 ) a predetermined radiation power is coupled out of the semiconductor chip. Method according to one of Claims 26 to 28, characterized in that the radiation emission region ( 16 ) is selected such that in the pulsed operation of the semiconductor chip ( 1 ) a predetermined modulation time is achieved. Method according to one of claims 26 to 29, characterized in that the semiconductor body ( 2 ) at least one growthable, in particular epitaxable, semiconductor layer ( 19 ) between the active zone ( 5 ) and the main surface ( 3 ), in particular the injection area ( 7 ), wherein the semiconductor layer is deliberately grown in such a way that the ratio of the area of the injection area to the area of the area of the radiation emission area ( 16 ) in the lateral direction covered area is greater than or equal to a predetermined value. Method according to one of claims 26 to 30, characterized in that the method for producing a semiconductor body ( 2 ) for a radiation-emitting semiconductor chip ( 1 ) is provided according to one of claims 1 to 25.