RADIATION-EMITTING SEMICONDUCTOR COMPONENT AND METHOD FOR PRODUCING RADIATION-EMITTING SEMICONDUCTOR COMPONENT

Abstract

A radiation-emitting semiconductor device (1) is specified, comprising a semiconductor body (2) having an active region (20) provided for generating radiation, a carrier (3) on which the semiconductor body is arranged and an optical element (4), wherein the optical element is attached to the semiconductor body by a direct bonding connection.

Furthermore, a method for producing of radiation-emitting semiconductor devices is specified.

Claims

1. A radiation-emitting semiconductor device comprising: a semiconductor body having an active region provided for generating radiation; and a carrier on which the semiconductor body is arranged; and an optical element, wherein: the optical element is attached to the semiconductor body with a direct bonding connection, the active region is arranged between a mirror region and a further mirror region, and the semiconductor body is completely free of elements for external electrical contacting on a side facing the optical element.

2. The radiation-emitting semiconductor device according to claim 1, wherein the mirror region is arranged between the active region and the optical element.

3. The radiation-emitting semiconductor device according to claim 1, wherein the mirror region and the further mirror region are part of the semiconductor body.

4. The radiation-emitting semiconductor device according to claim 1, wherein the semiconductor body comprises a first semiconductor region and a second semiconductor region, the first semiconductor region and the second semiconductor region are different from one another with respect of the charge type, the mirror region is a part of the second semiconductor region, and the further mirror region is a part of the first semiconductor region.

4. The radiation-emitting semiconductor device according to claim 1, wherein the optical element has a plurality of optical segments.

5. The radiation-emitting semiconductor device according to claim 1, wherein the optical element extends continuously over the active region.

6. The radiation-emitting semiconductor device according to claim 1, wherein the carrier and the optical element terminate flush with a side surface delimiting the radiation-emitting semiconductor device.

7. The radiation-emitting semiconductor device according to claim 1, wherein the mirror region is arranged between the active region and the direct bonding connection.

8. The radiation-emitting semiconductor device according to claim 1, wherein the radiation-emitting semiconductor device has two contacts for external electrical contacting on a side of the carrier facing away from the optical element.

9. The radiation-emitting semiconductor device according to claim 1, wherein a auxiliary bonding layer is arranged between the semiconductor body and the optical element.

10. The radiation-emitting semiconductor device according to claim 9, wherein the direct bonding connection is formed between the auxiliary bonding layer and a further auxiliary bonding layer.

11. The radiation-emitting semiconductor device according to claim 10, wherein the auxiliary bonding layer and the further auxiliary bonding layer each contain an oxide.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Further embodiments and expediencies result from the following description of the exemplary embodiments in connection with the Figures.

[0043] FIG. 1, FIG. 2, FIG. 3 and FIG. 4 each show an exemplary embodiment of a radiation-emitting semiconductor device using a schematic sectional view; and

[0044] FIGS. 5A, 5B, 5C and 5D and FIGS. 6A and 6B each show an exemplary embodiment of a method for producing radiation-emitting semiconductor devices on the basis of intermediate steps each represented in schematic sectional view.

DETAILED DESCRIPTION

[0045] Identical, similar or similar-acting elements are marked with the same reference signs in the Figures.

[0046] The Figures are all schematic representations and therefore not necessarily true to scale. Rather, comparatively small elements and in particular layer thicknesses can be shown in exaggerated size for clarification.

[0047] FIG. 1 shows an exemplary embodiment of a radiation-emitting semiconductor device. The radiation-emitting semiconductor device 1 has a semiconductor body 2 with an active region 20 provided for generating radiation. The semiconductor body 2 is arranged on a carrier 3. For example, the carrier is a growth substrate for the epitaxial deposition of the semiconductor layers of the semiconductor body. The carrier can also be different from the growth substrate. In this case, the carrier can be attached to the semiconductor body 2 by means of a bonding layer.

[0048] The semiconductor device 1 further has an optical element 4. The optical element 4 is attached to the semiconductor body 2 by a direct bonding connection 6. The direct bonding connection is exemplarily formed between an auxiliary bonding layer 61 and a further auxiliary bonding layer 62. For example, the auxiliary bonding layer 61 and the further auxiliary bonding layer 62 each contain an oxide, such as a silicon oxide. In contrast thereto, the semiconductor device 1 can, however, also have only one auxiliary bonding layer or no auxiliary bonding layer.

[0049] The optical element 4 is formed transmissive for the radiation to be generated in the active region 20. For example, the optical element 4 has a glass, gallium phosphide, gallium nitride or silicon. Silicon is particularly suitable for radiation in the infrared spectral range with a wavelength of at least 1100 nm.

[0050] The optical element 4 is exemplarily formed as a refractive optics, which for example collimates or focuses the radiation to be generated. In plan view of the semiconductor device, the optical element has, for example, a convexly curved radiation exit surface 40. However, the optical element can also be formed, for example, for a beam widening or, in general, for a beam shaping according to a predetermined radiation characteristic.

[0051] Furthermore the optical element 4 can also be formed as a diffractive optical element. In the case of a diffractive optical element, the mode of operation is not based on refraction, but rather on diffraction of the radiation impinging on the optical element.

[0052] The optical element 4 and the carrier 3 form in places a part of the side surface 11, which delimits the semiconductor device 1 in the lateral direction. A side surface 45 of the optical element and a side surface 30 of the carrier terminate flush with one another on the side surface 11 of the semiconductor device 1.

[0053] For the external electrical contacting, the semiconductor device 1 has two contacts, wherein one of the contacts is arranged on the side of the semiconductor body 2 facing the optical element 4. The optical element 4 has a breakthrough 41 in which the contact 5 is exposed for the electrical contacting, for example, by means of a bonding wire. The breakthrough 41 also extends through the auxiliary bonding layers 61, 62, if present.

[0054] The semiconductor device 1, for example, is formed as a surface-emitting laser or as a light-emitting diode with resonant cavity. The active region 20 is arranged between a mirror region 7 and further mirror region 75.

[0055] In the exemplary embodiment shown, both mirror region 7 and the further mirror region 75 are part of the semiconductor body. The electrical contacting of the active region 20 is carried out through the mirror region 7 and the further mirror region 75.

[0056] The semiconductor body 2 comprises a first semiconductor region 21 and a second semiconductor region 22, wherein the first semiconductor region and the second semiconductor region are different from one another with respect of the charge type, and the active region is arranged between the first semiconductor region 21 and the second semiconductor region 22. The active region 20 is thus located in a pn-junction. The mirror region 7 is a part of the second semiconductor region 22, and the further mirror region 75 is a part of the first semiconductor region 21.

[0057] For example, the active region is provided for generation radiation in the ultraviolet, visible or infrared spectral range.

[0058] The semiconductor body 2, in particular the active region 20, preferably contains III-V compound semiconductor material.

[0059] III-V compound semiconductor materials are particularly suitable for generating radiation in the ultraviolet (Al.sub.x In.sub.y Ga.sub.1-x-y N) over the visible (Al.sub.x In.sub.y Ga.sub.1-x-y N, in particular for blue to green radiation, or Al.sub.x In.sub.y Ga.sub.1-x-y P, in particular for yellow to red radiation) to the infrared (Al.sub.x In.sub.y Ga.sub.1-x-y As) spectral range. Here, 0x1, 0y1 and x+y1 apply in each case, in particular with x1, y1, x0 and/or y0. With III-V compound semiconductor materials, in particular from the material systems mentioned, high internal quantum efficiencies can further be achieved during radiation generation.

[0060] The exemplary embodiment shown in FIG. 2 substantially corresponds to the exemplary embodiment described in connection with FIG. 1. In contrast, the semiconductor device 1 has a plurality of segments 20A, 20B of the active region. The segments can be arranged next to one another in lateral direction, i.e. along a main plane of extension of the active region, in a rows-like or in a matrix-like manner.

[0061] The optical element 4 extends continuously over the segments 20A, 20B. The segments are each assigned to an optical segment 42, wherein the optical segments 42 are each formed in the same way with respect to their beam shaping properties. However, the optical segments 42 can differ from one another in terms of beam shaping. The segments 20A, 20B can each be externally electrically contacted independently of one another via assigned contacts 5. A contact 5 arranged on the side of the carrier 3 facing away from the semiconductor body 2 can form a common back contact for two or more, in particular all segments.

[0062] Such a segmentation of the active region can also be used for the exemplary embodiment described below.

[0063] The exemplary embodiment shown in FIG. 3 substantially corresponds to the exemplary embodiment described in connection with FIG. 1. In contrast, the mirror region 7 is arranged between the direct bonding connection 6 and the optical element 4. During the production of the semiconductor device, the mirror region 7 can thus be formed separately from the semiconductor body 2 on the optical element 4. For example, the mirror region 7 is formed by a Bragg mirror in the form of several dielectric layers, wherein adjacent layers differ from one another in terms of their refractive indices.

[0064] The layer of the mirror region 7 closest to the semiconductor body 2 also forms the interface for the production of the direct bonding connection 6. In contrast, as described in connection with FIG. 1, a further auxiliary bonding layer can also be provided.

[0065] The exemplary embodiment shown in FIG. 4 substantially corresponds to the exemplary embodiment described in connection with FIG. 1.

[0066] In contrast thereto, the semiconductor device 1 has two contacts 5 for external electrical contacting on the side of the semiconductor body 2 facing away from the optical element 4, in particular on the side of the carrier 3 facing away from the optical element. On the side facing the optical element 4, the semiconductor body 2 is completely free of elements for external electrical contacting. The optical element 4 can completely cover the semiconductor body 2 without affecting the external electrical contacting of the semiconductor device 1. The second semiconductor region 22, which is arranged on the side of active region 20 facing away from carrier 3, is electrically contacted via a recess 25 in the semiconductor body. The recess 25 extends in particular through the active region 20. To avoid an electrical short of the active region 20, the recess is lined with an insulating layer 26.

[0067] FIGS. 5A to 5D show an exemplary embodiment of a method for producing semiconductor devices, wherein only one semiconductor device is produced exemplarily as described in connection with FIG. 1.

[0068] As shown in FIG. 5A, a semiconductor layer sequence 29 with an active region 20 provided for generating radiation is provided on a carrier 3. The semiconductor layer sequence 2 can already be structured into a plurality of semiconductor bodies in lateral direction. This is not shown for simplification.

[0069] A contact 5 is arranged on the side of the semiconductor layer sequence 29 facing away from carrier 3. An auxiliary bonding layer 61 completely covers the contact 5 and fills the interspaces 51 between the contacts 5. In the interspaces 51 the auxiliary bonding layer adjoins the semiconductor layer sequence 29. The auxiliary bonding layer 61 forms a first interface 81. Subsequently, the first interface 81 is levelled if necessary, as shown in FIG. 5B, for example by chemo-mechanical polishing.

[0070] An optics carrier 49 is provided, wherein the optics carrier in the exemplary embodiment shown has a plurality of optical elements 4 (FIG. 5B). The optical elements 4 are formed continuously in the optics carrier 49. The optics carrier 49 completely covers the semiconductor layer sequence 29. A second interface 82 of the optics carrier 49 is exemplarily formed by means of a further auxiliary bonding layer 62.

[0071] A high-precision relative adjustment between the optics carrier 49 and the carrier 3 with the semiconductor layer sequence 29 can be achieved, for example, by means of alignment marks, which can be arranged at the edge of the optics carrier 49 and/or the carrier 3 with the semiconductor layer sequence 29. These are arranged outside the semiconductor devices to be produced and are therefore not explicitly shown in the Figures. Thus, accuracies of 1 m or less of the relative adjustment between optics carrier and semiconductor layer sequence in lateral direction can be achieved.

[0072] Subsequently, a direct bonding connection 6 is produced between the first interface 81 and the second interface 82, as shown in FIG. 5C.

[0073] The contacts 5 are exposed. For this purpose, a plurality of breakthroughs 41 are formed in the optics carrier 49, for example by etching.

[0074] Finally, a separation into a plurality of semiconductor devices 1 is performed along separation lines 9 (FIG. 5D). During separation, the optics carrier 49 and the carrier 3 with the semiconductor layer sequence 29 are severed in such a way that the finished semiconductor devices each have a part of the carrier 3, a semiconductor body 2 formed from the semiconductor layer sequence 29 and an optical element 4. After separation, it is therefore no longer necessary to apply an optical element to each individual semiconductor device.

[0075] Separation can be carried out mechanically, for example by sawing, chemically, for example by etching, or by means of coherent radiation, for example by a laser separation process.

[0076] FIGS. 6A and 6B show another exemplary embodiment of a method. This exemplary embodiment substantially corresponds to the exemplary embodiment described in connection with FIGS. 5A to 5D.

[0077] In contrast thereto, the optics carrier 49 is attached to the carrier 3 with the semiconductor layer sequence 29 in a completely unstructured lateral direction by means of a direct bonding connection 6 (FIG. 6A). Only subsequently, the optics carrier 49 is processed at a radiation exit surface 40 facing away from the semiconductor layer sequence 29 in order to form the optical elements 4 (FIG. 6B). This can be carried out by an etching process, for example. In this case, a high-precision adjustment of the optics carrier 49 relative to the carrier 3 with the semiconductor layer sequence 29 can be dispensed with.

[0078] The further steps, such as the separation, can be carried out as described in connection with FIGS. 5A to 5D.

[0079] The invention is not limited by the description based on the exemplary embodiments. Rather, the invention comprises any new feature as well as any combination of features, which in particular includes any combination of features in the claims, even if this feature or combination itself is not explicitly stated in the claims or the exemplary embodiments.