WO2019043003A1

WO2019043003A1 - Method for producing a plurality of radiation-emitting semiconductor chips, radiation-emitting semiconductor chip and radiation-emitting semiconductor chip array

Info

Publication number: WO2019043003A1
Application number: PCT/EP2018/073132
Authority: WO
Inventors: Martin Rudolf Behringer; Christian Müller
Original assignee: Osram Opto Semiconductors Gmbh
Priority date: 2017-08-31
Filing date: 2018-08-28
Publication date: 2019-03-07
Also published as: DE102017120037A1

Abstract

The invention relates to a method for producing a plurality of radiation-emitting semiconductor chips, comprising the steps of: - providing a growth substrate (1), - epitaxial growing of an epitaxial semiconductor layer sequence (2) having an active zone (3), which is suitable for generating electromagnetic radiation, on the growth substrate (1), wherein the semiconductor layer sequence (2) comprises a nitride compound semiconductor material, - applying a structured photoresist layer (4) having hexagonal or triangular structural elements (5) to the semiconductor layer sequence (2), wherein regions of the semiconductor layer sequence (2) between the structural elements (5) are freely accessible, and - etching the semiconductor layer sequence (2) in the freely accessible regions so as to create hexagonal or triangular semiconductor layer stacks (2) having lateral surfaces (11), of which at least one lateral surface (11) extends parallel to an m-surface (7) or parallel to an a-surface (6) of the nitride compound semiconductor material, wherein the semiconductor layer stacks are in the form of six-sided or three-sided prisms, and the active zone stands perpendicular to the lateral surfaces of the semiconductor layer stacks.

Description

description

METHOD FOR THE PRODUCTION OF A VARIETY OF RADIATION-EMITTING SEMICONDUCTOR CHIPS, RADIATION-EMITTING SEMICONDUCTOR CHIP AND

RADIATION-EMITTING SEMICONDUCTOR CHIP ARRAY

There will be a method of manufacturing a plurality of radiation-emitting semiconductor chips

radiation-emitting semiconductor chip and a

radiation-emitting semiconductor chip array indicated.

One object in the present case is to specify a method for producing an improved radiation-emitting semiconductor chip, an improved semiconductor chip and an improved radiation-emitting semiconductor chip array.

In particular, a semiconductor chip is to be specified which has a comparatively small radiation exit area with increased efficiency. Furthermore, a should

radiation-emitting semiconductor chip array can be given with increased efficiency.

These objects are achieved by a method having the steps of claim 1, by a radiation-emitting semiconductor chip having the features of patent claim 11 and by a radiation-emitting semiconductor chip array having the features of patent claim 16.

Advantageous embodiments and further developments of

Method, the semiconductor chip and the semiconductor chip array are the subject of the respective dependent claims. According to one embodiment of the method for producing a plurality of radiation-emitting semiconductor chips, a growth substrate is first provided. The

Growth substrate may include, for example, sapphire, gallium nitride, silicon carbide or silicon or consist of one of these materials.

According to a further embodiment of the method, an epitaxial semiconductor layer sequence with an active zone, which is suitable for generating electromagnetic radiation, is epitaxially grown on the growth substrate. The epitaxial semiconductor layer sequence is here

particularly preferably from a

Nitride compound semiconductor material formed or comprises a nitride compound semiconductor material.

Nitride compound semiconductor materials are

Compound semiconductor materials containing nitrogen, such as the materials of the system In _x Al _y Gai _x - _y N with 0 <x <1, 0 <y <1 and x + y <1. For example, the nitride compound semiconductor material is GaN or AlInGaN.

Based the epitaxial semiconductor layer sequence and

especially the active zone on one

Nitride compound semiconductor material, it is particularly preferred short-wave visible radiation, for example from the ultraviolet, blue or green spectral range generated in the active zone.

According to a further embodiment of the method, a structured photoresist layer with hexagonal or

triangular structural elements on the

Semiconductor layer sequence applied. Here are areas the semiconductor layer sequence between the structural elements particularly preferably freely accessible.

According to a further embodiment of the method, the semiconductor layer sequence is etched in the freely accessible regions, so that hexagonal or triangular

Semiconductor layer stack arise with side surfaces, of which at least one side surfaces parallel to an m-surface or parallel to an a-surface of the

Nitride compound semiconductor material runs. The

Side surface may also be formed by the m-surface or by the a-surface of the nitride compound semiconductor material. By the term "parallel" is meant here that the

Side surface with the m-surface or the a-surface forms an angle which is not greater than 5 °, more preferably not greater than 1 °. In particular, in this embodiment of the method for producing hexagonal semiconductor layer stacks, hexagonal structural elements and for producing triangular semiconductor layer stacks are triangular structural elements

used. When triangular semiconductor layer stacks are generated, a side surface of the triangular one runs

Semiconductor layer stack preferably parallel to the a-surface.

Thereafter, further steps may be taken, such as applying a metallization, inspection or removal of the photoresist layer.

The nitride compound semiconductor material, such as GaN or AlInGaN, is usually hexagonal Crystal structure, in particular a

Wurzit crystal structure. At the a-surface of the

Nitride compound semiconductor material is in the

Usually around the non-polar (ll20) surface of the hexagonal

Crystal structure, while it is in the m-surface in the

Usually around the non-polar (llOO) surface of the

hexagonal crystal structure. Furthermore, a nitride compound semiconductor material with hexagonal

Crystal structure usually a c-surface, which is usually in the polar (OOOl) surface. On the c surface is a c-axis of the crystal structure

vertical.

The side surfaces of the semiconductor layer stacks are

preferably between a first main surface of the respective

Semiconductor layer stack and a second major surface of the respective semiconductor layer stack arranged. The first main surface and the second main surface of the

Semiconductor layer stacks are preferably parallel to the c-face of the nitride compound semiconductor material and in the

Usually also arranged parallel to a c-surface of the growth substrate or through the c-surface of the

Nitride compound semiconductor material formed. The

Side surfaces are preferably perpendicular to the c-surface.

According to a further embodiment of the method, the patterned photoresist layer with the below

described steps on the epitaxial

Semiconductor layer sequence applied. First, a photoresist layer is applied over the entire surface of the semiconductor layer sequence, for example by means of spinning. Then the photoresist layer is exposed with a mask, wherein the mask has hexagonal or triangular structural elements. The In this case, the mask is particularly preferably adjusted such that at least one side surface of each structure element of the mask runs parallel to the m surface or parallel to the a surface of the nitride compound semiconductor material. Become

creates triangular structural elements, so runs one

Side surface of the triangular structural element of the mask preferably parallel to the a-surface. After exposure, the photoresist layer is preferably developed so that the

Structure elements arise.

According to a further embodiment of the method, in the etching of the semiconductor layer sequence, the active zone of the semiconductor layer sequence is completely severed. According to a further embodiment of the method, the semiconductor layer sequence with a dry-chemical

Etched or etched using a wet-chemical etching process. Particularly preferably arise in the dry ^¬ chemical etching or in the wet-chemical

Etching the side surfaces of the semiconductor layer stack. Preferably, the active zone is perpendicular to the

Side surfaces of the semiconductor layer stacks. Preferably, the side surfaces cover the active zone. Furthermore, it is also possible that the

Semiconductor layer sequence is first cut with the dry-chemical etching process and then the resulting

Side surfaces of the semiconductor layer stacks are smoothed with the wet chemical etching process. Particularly preferred arise in this embodiment of the method

Side surfaces of the semiconductor layer stacks, which are as free as possible of defects, such as steps and edges. Particularly preferably, the side surfaces of the Semiconductor layer stacks do not have steps parallel to the c-axis of the nitride compound semiconductor material.

According to a further embodiment of the method, a mirror layer is applied to a first main surface of the semiconductor layer sequence facing away from the growth substrate. Particularly preferably, the mirror layer is suitable for particularly well reflecting electromagnetic radiation that is generated in the active zone. The mirror layer may, for example, have a metallic layer or consist of a metallic layer. Furthermore, it is also possible that the mirror layer as a Bragg reflector

is trained. For example, the mirror layer can serve as an electrical contact for the semiconductor layer sequence. For this purpose, the mirror layer must be electrically conductive.

According to a further embodiment of the method, a carrier is applied to the mirror layer and the

Growth substrate removed below. For example, the growth substrate can be removed by means of a laser lift-off method, by means of an etching process, by polishing or grinding. Alternatively, it is also possible for the growth substrate to remain in the semiconductor chips.

Is the growth substrate no longer of the finished one

Semiconductor chip comprises, so the second main surface of the semiconductor layer stack preferably to a

Radiation exit surface of the semiconductor chip, while the first main surface to a mounting surface of the finished

Semiconductor chips points. If, however, the growth substrate is still covered by the finished semiconductor chip, then the first main surface of the semiconductor layer stack preferably has one

Radiation exit surface of the semiconductor chip, while the second main surface to a mounting surface of the finished

Semiconductor chips points.

The carrier may be, for example, a

Silicon carrier or a wafer with an integrated circuit ("IC wafer") act. The carrier serves to mechanically stabilize the semiconductor layer sequence.

In addition, it is possible for the semiconductor chip to be supplied with current via the carrier.

According to a further embodiment of the method, an electrical contact is applied to one of the main surfaces of the semiconductor layer sequence, which faces away from the mounting surface of the semiconductor chip. In the electric

Contact may be, for example, a transparent contact layer, the entire surface on the second

Main surface of the semiconductor layer sequence is applied.

The electrically transparent contact layer can

For example, a transparent conductive oxide (TCO for

Transparent conductive oxides are generally metal oxides, such as zinc oxide, tin oxide, cadmium oxide, titanium oxide, indium oxide or indium tin oxide (ITO), in addition to binary metal oxygen compounds, such as

for example, ZnO, SnO ₂ or Ιη ₂ θ3 also include ternary

Metal oxygen compounds such as Zn ₂ SnO ₄ , ZnSnO 3, Mgln ₂ O ₄ , GalnO 3, Zn _{2 In} ₂ O or In ₄ Sn ₂ O ₂ or mixtures different transparent conductive oxides to the group of TCOs. Furthermore, the TCOs do not necessarily correspond to a stoichiometric composition and may furthermore also be p- and n-doped.

The transparent contact layer may also comprise graphene or consist of graphene.

Furthermore, it is also possible that the electrical contact is a metallic frame or comprises a metallic frame. For example, the metallic frame completely surrounds a radiation exit surface of each semiconductor chip.

Furthermore, it is also possible that the electrical contact both the transparent contact layer and the

metallic frame or transparent

Contact layer and the metallic frame is formed.

By way of example, the transparent contact layer is applied over the entire surface of the first main area or the second main area of the semiconductor layer sequence, and the metallic one

Frame again in direct contact on the transparent

Contact layer arranged.

According to a further embodiment of the method, the semiconductor chips are singulated so that each semiconductor chip comprises a single semiconductor layer stack.

Furthermore, it is also possible that when separating a plurality of semiconductor layer stack in a composite

be summarized, so that a semiconductor chip array is formed. In other words, the wafer that is the

epitaxial semiconductor layer sequence comprises, so isolated, that several semiconductor layer stacks remain in a composite.

The method described here is in particular

suitable to a radiation-emitting semiconductor chip or a radiation-emitting semiconductor chip array

produce. Embodiments, features and elements described herein in connection with the method may therefore also be used in the radiation-emitting

Semiconductor chip or the radiation-emitting

Semiconductor chip array can be realized and vice versa.

A radiation-emitting semiconductor chip according to an embodiment comprises a semiconductor layer stack with an active zone. The active zone is suitable for generating electromagnetic radiation. Particularly preferably, the semiconductor layer stack comprises a

Nitride compound semiconductor material or is made of a

Nitride compound semiconductor material formed. In particular, the active zone is particularly preferred by a

According to an embodiment of the radiation-emitting

Semiconductor chips, the semiconductor layer stack has a hexagonal or triangular base. Preferably, a base area of the semiconductor chip is defined by the base area of the semiconductor layer stack. The base area of the semiconductor chip is likewise preferably hexagonal or triangular. For example, the semiconductor chip and / or the semiconductor layer stack are formed as a six-sided or three-sided prism. The base area and a top surface of the six-sided prism are preferred as Hexagon trained. The base surface and a top surface of the three-sided prism are preferably formed as a triangle. The top surface of the prism is hereby preferably the

Base of the prism opposite. Preferably, the prism is straight.

Particularly preferred is at least one side surface of the

Semiconductor layer stack parallel to the m-surface or

parallel to the a-surface of the

Aligned Nitridverbindungshalbleitermaterials. Furthermore, it is also possible for at least one side face of the semiconductor layer stack to be formed by the m face or the a face of the nitride compound semiconductor material. In a triangular semiconductor layer stack, a side surface is preferably parallel to the a surface.

Particularly preferably, a side edge of the base area of the semiconductor layer stack and / or of the semiconductor chip is not larger than 30 micrometers. Particularly preferred is a

Side edge of the base of the semiconductor layer stack and / or the semiconductor chip not larger than 1 micron.

According to an embodiment of the radiation-emitting

Semiconductor chip has this a carrier on which the semiconductor layer stack is arranged. In this case, the carrier is particularly preferably different from the growth substrate. Between the carrier and the semiconductor layer stack, a mirror layer is preferably arranged. The mirror layer is intended to electromagnetic radiation generated in the active region of the semiconductor chip to a

To direct radiation exit surface of the semiconductor chip.

Particularly preferably, the mirror layer is designed to be electrically conductive, so that the semiconductor chip has its own Mounting surface, which is opposite to a radiation exit surface, can be electrically contacted.

According to another embodiment, the semiconductor chip is free of a carrier and a growth substrate. In this embodiment, the semiconductor layer stack is preferably arranged on a metallic carrier layer, for example in direct contact. The metallic one

Carrier layer is, for example, electrodeposited. The metallic carrier layer stabilizes the

Semiconductor layer sequence preferably mechanically. For example, the metallic support layer has a thickness between 2 microns inclusive and 10 microns inclusive. Particularly preferably, the metallic carrier layer acts as a mirror, the electromagnetic radiation generated in the active zone of the semiconductor chip to the

Radiation exit surface of the semiconductor chip directs.

According to another embodiment of the

Radiation-emitting semiconductor chips, an electrical contact is disposed on one of the two main surfaces of the semiconductor layer stack, which is a transparent

Contact layer and / or a metallic frame comprises. The hexagonal or triangular ones described here

Semiconductor chips and / or those described here

Semiconductor layer stacks are particularly preferably part of a semiconductor chip array. A radiation-emitting semiconductor chip array preferably comprises a multiplicity of semiconductor layer stacks.

Preferably, each semiconductor layer stack has an active zone suitable for electromagnetic radiation to create. The semiconductor layer stacks preferably comprise a nitride compound semiconductor material or are formed of a nitride compound semiconductor material. Particularly preferably, each semiconductor layer stack has a

hexagonal or triangular base. Preferably, at least one side surface extends each

Semiconductor layer stack parallel to the m-surface or

parallel to the a-surface of the

Nitride compound semiconductor material.

Preferably, the semiconductor layer stacks are one

Radiation-emitting semiconductor arrays on a

arranged common carrier. In this case, the carrier particularly preferably has an integrated circuit for controlling the semiconductor layer stacks. Everyone is here

Semiconductor layer stack particularly preferably electrically connected via the main surface facing the mounting surface electrically connected to the integrated circuit. In this embodiment of the radiation-emitting semiconductor chip array, the semiconductor layer stacks are particularly preferably over their main sides facing the radiation exit area

electrically connected to each other.

According to another embodiment of the

radiation-emitting semiconductor chip arrays, each has

Semiconductor layer stack a hexagonal or a

triangular radiation passage surface, which is circulated by a metallic frame. The

Radiation passage surface points to a

Radiation exit surface of the semiconductor chip array or forms the radiation exit surface at least partially.

For example, the radiation passage area of the

Semiconductor layer stack further layers applied, of which the outermost layer at least partially the radiation exit surface of the semiconductor chip array

trains. The metallic frame alone or together with the transparent contact layer serves as an electrical contact for the semiconductor layer stack. Particularly preferred are the

Semiconductor layer stack in this embodiment of the radiation-emitting semiconductor chip arrays via webs electrically connected to each other, the

metallic frame adjacent semiconductor layer stack electrically conductively interconnect. The webs are preferably formed metallic. The semiconductor chip array can, for example, in one

Find headlight for a motor vehicle use. In this case, individual semiconductor layer stacks are particularly preferably switched on and off, for example using a carrier with an integrated circuit. In this way, the emission characteristics of the headlamp can be adjusted as desired, such as dipped beam,

High beam or curve lighting.

Furthermore, it is also possible that the semiconductor chip array is used as a structured light source in a display or in a spotlight for a stage lighting. Again, it may be useful and desirable to have parts of

Switch semiconductor chip arrays arbitrarily on or off to change the radiation characteristic desired.

In the present case, it is an idea, comparatively small

Semiconductor chips, such as with edge lengths less than or equal to 30 microns or even less than or equal to 1 microns, form hexagonal or triangular and the side surfaces of the semiconductor chip on the crystal surfaces of

Orienting nitride compound semiconductor material on which the semiconductor chip is based. Furthermore, the

Side surfaces of the semiconductor chip preferably generated by etching.

In this way, comparatively small

Radiation-emitting semiconductor chips are produced which have few or no defects on their side surfaces

respectively. Such defects, such as dangling bonds, can lead to leakage and non-radiative

Recombination that reduce the efficiency of the semiconductor chip. Defects in edge regions of the semiconductor chips are particularly disadvantageous in particular if the size of the semiconductor chip is comparatively small and the

Edge regions therefore comprise a comparatively large proportion of the surface of the semiconductor chip. Further advantageous embodiments and developments of the invention will become apparent from the embodiments described below in conjunction with the figures.

On the basis of the schematic representations of Figures 1 to 13, a method for producing an optoelectronic semiconductor chip and for producing a

Radiation emitting semiconductor chip arrays according to an embodiment explained in more detail. Figure 14 shows a schematic plan view of a

A radiation-emitting semiconductor chip according to a

Embodiment. Figure 15 shows a schematic plan view of a

Radiation-emitting semiconductor chip array according to an embodiment. FIG. 16 shows a schematic sectional representation of a radiation-emitting semiconductor chip array according to one exemplary embodiment.

Figure 17 shows a schematic plan view of the

radiation-emitting semiconductor chip array according to FIG. 16.

FIG. 18 shows a schematic plan view of one

radiation-emitting semiconductor chip array according to another embodiment.

Based on the schematic plan views of FIGS. 19 and 20, semiconductor layer stacks with a triangular base are explained in greater detail according to one embodiment. The same, similar or equivalent elements are provided in the figures with the same reference numerals. The figures and the proportions of the elements shown in the figures with each other are not to scale

consider. Rather, individual elements, in particular layer thicknesses, can be shown exaggeratedly large for better representability and / or better understanding.

In the method according to the exemplary embodiment of FIGS. 1 to 13, in a first step, a growth substrate 1 is provided, to which an epitaxial growth element 1 is provided

Semiconductor layer sequence 2 is epitaxially grown. FIG. 1 shows a sectional view through the

Composite of growth substrate 1 and epitaxial Semiconductor layer sequence 2, while the figure 2 a

schematic plan view of the epitaxial

Semiconductor layer sequence 2 represents. The epitaxial semiconductor layer sequence 2 is in the present case formed from a nitride compound semiconductor material and has an active zone 3 which is suitable for

to generate electromagnetic radiation. Particularly preferably, the active zone 3 is suitable for blue light

produce. The growth substrate 1 is

for example, a sapphire wafer.

In a next step, which is shown schematically in FIGS. 3 and 4, reference is made to the epitaxial

Semiconductor layer sequence 2 over the entire surface of a photoresist layer 4 applied. The figure 4 is again a schematic

Top view of the composite of the schematic

Sectional view of Figure 3. In a next step, which is shown schematically in Figures 5 and 6, the photoresist layer 4

structured. For this purpose, a mask is preferably used which has hexagonal structural elements (not

shown). With the aid of the mask, the photoresist layer 4 is patterned into hexagonal structural elements 5, which leaves areas of the epitaxial semiconductor layer sequence 2 free.

The nitride compound semiconductor material of the epitaxial semiconductor layer sequence 2 in this case has a hexagonal crystal structure with an a-surface 6, an m-surface 7 and a c-surface 8. The unit cell of hexagonal

Crystal structure is to explain the a-surface 6, the m- Surface 7 and the c-surface 8 shown schematically in Figures 7 to 9.

The unit cell of the hexagonal crystal structure is formed as a prism having a hexagonal base whose corners are each formed by a gallium atom 9. The c-area 8 of the unit cell with the Miller indices (0001) is shown hatched in FIG. The c-surface 8 forms a top surface of the prism. The m-area 7 of the unit cell with the Miller indices (1100) is shown hatched in FIG. The m-surface 7 forms a side surface of the prism. The a-surface 6 of

A unit cell with the Miller indices (1120) is shown hatched in FIG. The a-surface 6 is an area that runs inside the unit cell. The a-surface 6 is perpendicular to the c-surface 8 and connects two corner points of the unit cell, between which a single further corner is arranged. In the present case, the epitaxial semiconductor layer sequence 2 has grown epitaxially in such a way that its main surfaces are arranged parallel to the c-surface 8 of the unit cell.

In the present case, the structural elements of the mask are preferably adjusted such that at least one of their edges runs parallel to the m-surface 7 or parallel to the a-surface 6. In this way, structural elements 5 in the

Photoresist layer 4 generated, which also extend parallel to the m-surface 7 or parallel to the a-surface 6.

In a next step, shown schematically in FIGS. 10 and 11, the epitaxial

Semiconductor layer sequence 2 through the freely accessible Etched areas in the photoresist layer 4, for example by dry etching and / or wet chemical etching, so that semiconductor layer stack 10 arise on the growth substrate 1, which are completely separated from each other. The semiconductor layer stacks 10 have a hexagonal

Base area up. Furthermore, at least one runs

Side surface 11 of each semiconductor layer stack 10 parallel to the a-surface 6 or parallel to the m-surface 7 of the

Nitride compound semiconductor material.

In a further step, on the freely accessible first main surface of the semiconductor layer stack 10 a

Mirror layer 12 can be applied, which is adapted to radiation generated in the active zone 3 to

reflect. Then, a carrier 13 is applied to the mirror layer 12 and the growth substrate 1 is removed. On a second main surface of the semiconductor layer stack 10, which is opposite to the first main surface, a transparent contact layer 14 is further applied. The composite produced in this way is shown schematically in FIGS. 12 and 13, wherein FIG. 12 is a schematic sectional view and FIG. 13 is a schematic sectional view

Show top view. In a next step, the bond with the

Semiconductor layer stacks 10 isolated. For example, the composite can be singulated so that individual

Radiation-emitting semiconductor chips are formed, each of which comprises a single semiconductor layer stack 10.

A plan view of a radiation-emitting

Semiconductor chip comprising a single semiconductor layer stack 10 is schematically shown in FIG. 14, for example shown. The semiconductor chip has like the

Semiconductor layer stack 10 has a hexagonal base. At least one side surface 11 of the

Semiconductor layer stack 10 is parallel to the a-surface 6 or parallel to the m-surface 7 of the

Nitride compound semiconductor material of

Semiconductor layer stack 10 is arranged.

Furthermore, it is also possible that the composite with the

Variety of semiconductor layer stacks 10 is singled so that a radiation-emitting semiconductor chip array is formed comprising a plurality of semiconductor layer stacks 10. Such a radiation-emitting semiconductor chip array is shown schematically, for example, in FIG. The semiconductor layer stacks 10 of the semiconductor chip array according to the exemplary embodiment of FIG. 15 each have a hexagonal base surface, wherein a side surface 11 of each semiconductor layer stack 10 is parallel to the a surface 6 or parallel to the m surface 7 of FIG

Nitride compound semiconductor material is arranged.

The radiation-emitting semiconductor chip array according to the exemplary embodiment of FIGS. 16 and 17 has a

common carrier 13, which comprises an integrated circuit. An electrical control element 15 of the integrated circuit is, for example, below the

Semiconductor layer stack 10 shown. Between the

Carrier 13 and the semiconductor layer stack 10 in the present case, a mirror layer 12 is arranged. On the first main surface of the semiconductor layer stack 10 is a transparent

Contact layer 14 and a metallic frame 16 applied, the radiation passage area of the

Semiconductor layer stack 10 completely rotates.

In the semiconductor chip array according to the exemplary embodiment of FIG. 18, adjacent semiconductor layer stacks 10 are electrically conductively connected via the metal frames 16 by way of webs 17. About the electrical controls 15 of the integrated circuit of the carrier 13, the

individual semiconductor layer stack 10 individually switched on and off.

In contrast to the embodiment of Figures 1 to 18, the semiconductor chip array according to the

Embodiment of Figure 20 semiconductor layer stack 10 with a triangular base. The

Semiconductor layer stacks 10 are straight as triangular

Prisms formed, wherein a top surface of each prism has a radiation exit surface. Figure 19 shows schematically as a triangular

Semiconductor layer stack 10 is preferably arranged with respect to a hexagonal semiconductor layer stack 10, each based on a nitride compound semiconductor material. The side surface 11 of a triangular

Semiconductor layer stack 10 in this case connects two corners of the hexagonal semiconductor layer stack 10, between which another corner of the hexagonal

Semiconductor layer stack 10 is arranged. The

Side face 11 of the triangular semiconductor layer stack 10 runs parallel to an a face 6 of FIG

Nitride compound semiconductor material. The present application claims the priority of the German application DE 102017120037.1, whose

The disclosure is hereby incorporated by reference. The invention is not limited by the description based on the embodiments of these. Rather, the invention encompasses every new feature as well as every combination of features, which in particular includes any combination of features in the patent claims, even if this feature or combination itself is not explicitly incorporated in the claims

Claims or embodiments is given.

Reference sign list

1 growth substrate

2 epitaxial semiconductor layer sequence 3 active zone

4 photoresist layer

5 structural element

6 a surface

7 m area

8 c area

9 gallium atom

10 semiconductor layer stacks

11 side surface

12 mirror layer

13 carriers

14 transparent contact layer

15 electrical control

16 metallic frame

17 footbridge

Claims

claims

1. A process for producing a variety

radiation-emitting semiconductor chips with the following steps:

Providing a growth substrate (1),

Epitaxial growth of an epitaxial

A semiconductor layer sequence (2) having an active region (3) suitable for generating electromagnetic radiation is applied to the growth substrate (1), wherein the

Semiconductor layer sequence (2)

Comprises nitride compound semiconductor material,

Applying a structured photoresist layer (4) with hexagonal or triangular structural elements (5) to the semiconductor layer sequence (2), wherein regions of the

Semiconductor layer sequence (2) between the structural elements (5) are freely accessible, and

- Etching the semiconductor layer sequence (2) in the free

accessible areas such that hexagonal or triangular semiconductor layer stacks (2) with side surfaces (11)

arise, of which at least one side surface (11)

parallel to an m-surface (7) or parallel to an a-surface (6) of the nitride compound semiconductor material, wherein

- The semiconductor layer stack as six-sided or

three-sided prisms are formed, and

- the active zone perpendicular to the side surfaces of the

Semiconductor layer stack is.

2. Method according to the preceding claim, in which the structured photoresist layer (4) is applied to the epitaxial semiconductor layer sequence (2) by the following steps: - full-surface application of a photoresist layer (4) on the semiconductor layer sequence (2),

- exposing the photoresist layer (4) with a mask having hexagonal or triangular structural elements (5), wherein the mask is adjusted so that at least one

Side surface (11) of each structural element (5) parallel to the m-surface (7) or parallel to the a-surface (6) of the

Nitride compound semiconductor material runs.

3. The method according to any one of the above claims, wherein in the etching, the active zone (3) of the semiconductor layer sequence (2) is completely severed.

4. The method according to any one of the above claims, wherein the semiconductor layer sequence (2) is etched by a dry-chemical etching process or by a wet-chemical etching process, so that the side surfaces (11) of the

Semiconductor layer stack (2) arise.

5. The method according to any one of the above claims, ^wherein the semiconductor ^{layer sequence} (2) is first severed by a dry ^¬ chemical etching process and then the

resulting side surfaces (11) of the semiconductor layer stack (2) are smoothed with a wet-chemical etching process.

6. The method according to any one of the above claims, wherein

- On a the growth substrate (1) facing away from the first main surface of the semiconductor layer sequence (2) a

Mirror layer (12) is applied,

- On the mirror layer (12), a carrier (13) is applied, and

- The growth substrate (1) is removed.

7. The method according to any one of the above claims, wherein on a main surface of the semiconductor layer sequence (2) a

electrical contact is applied.

8. The method according to the preceding claim, wherein the electrical contact comprises a transparent contact layer (14) and / or a metallic frame (16).

9. The method according to any one of the above claims, wherein the semiconductor chips are singulated so that each

Semiconductor chip comprises a single semiconductor layer stack (10).

10. The method according to any one of claims, wherein the

Separate a plurality of semiconductor layer stacks (10) are combined in a composite, so that a semiconductor chip array is formed.

11. Radiation-emitting semiconductor chip with a

Semiconductor layer stack (2) comprising an active region (3) adapted to generate electromagnetic radiation, wherein

- The semiconductor layer stack (10) a

Comprises nitride compound semiconductor material,

the semiconductor layer stack (2) has a hexagonal or triangular base area,

- At least one side surface (11) of the

Semiconductor layer stack (2) parallel to the m-surface (7) or parallel to the a-surface (6) of the

Nitride compound semiconductor material runs,

- The semiconductor layer stack is formed as a six-sided or three-sided prism, and - the active zone perpendicular to the side surfaces of the

Semiconductor layer stack is.

12. Radiation-emitting semiconductor chip after the

Previous claim, wherein a side edge of the base of the semiconductor layer stack (10) is not greater than 30 microns.

13. The radiation-emitting semiconductor chip according to one of claims 11 to 12, which has a carrier (13) on which the semiconductor layer stack (10) is arranged, wherein a mirror layer (12) is arranged between the carrier (13) and the semiconductor layer stack (10) ,

14. A radiation-emitting semiconductor chip according to one of claims 11 to 13, wherein on a main surface of the

Semiconductor layer stack (10) is arranged an electrical contact comprising a transparent contact layer (14) and / or a metallic frame (16).

15. A radiation-emitting semiconductor chip according to any one of claims 11 to 14, wherein the side surfaces cover the active zone.

16. A radiation-emitting semiconductor chip array having a plurality of semiconductor layer stacks (10), wherein

each semiconductor layer stack comprises an active zone suitable for generating electromagnetic radiation;

- The semiconductor layer stack (10) a

Comprise nitride compound semiconductor material,

each semiconductor layer stack (10) has a hexagonal or triangular base area, - At least one side surface (11) each

Semiconductor layer stack (10) parallel to the m-surface (7) or parallel to the a-surface (6) of the

Nitride compound semiconductor material runs,

- The semiconductor layer stack as six-sided or

three-sided prisms are formed, and

- the active zone perpendicular to the side surfaces of the

Semiconductor layer stack is.

17. A radiation-emitting semiconductor chip array according to the preceding claim, wherein

- The semiconductor layer stacks (10) are arranged on a common carrier (13) having an integrated circuit for controlling the semiconductor layer stack (10), - Each semiconductor layer stack (10) via a first

Main surface is electrically connected to the integrated circuit, and

- The semiconductor layer stack (10) via their second

Main pages are electrically connected to each other.

18. A radiation-emitting semiconductor chip array according to the preceding claim, wherein

- Each semiconductor layer stack (10) on its second major surface a hexagonal or triangular

Radiation passage surface, of a

circulating metallic frame (16), which serves as an electrical contact, and

- The semiconductor layer stack (10) via webs (17)

electrically conductively connected to each other, the metallic frame (16) adjacent

Semiconductor layer stack (10) electrically conductively interconnect.