DE102013113191A1 - Method for producing optoelectronic components for the encapsulation of layers - Google Patents

Abstract

The invention relates to a method for producing optoelectronic components for the encapsulation of layers. For this purpose, a carrier (1) with a carrier main side (10) is provided. On the carrier main side (10) of the carrier (1), a mask (2) is applied. The mask (2) has a first mask layer (21) and a second mask layer (22). Furthermore, the mask (2) has at least one opening (200) which completely penetrates the mask (2) in the direction perpendicular to the carrier main side (10). Furthermore, the first mask layer (21) has at least one undercut (201) with respect to the second mask layer (22) in the area of the opening (200). After the mask (2) has been applied to the carrier (1), a functional material (4) is deposited such that at least one material structure (41) arranged on the carrier main side (10) is formed in the area of the opening (200). Subsequently, a capsule layer (5) is deposited on at least the material structure (41). The capsule layer (5) is deposited such that before the application of the capsule layer (5) exposed sides of the material structure (41) are completely covered with the capsule layer (5). In a further step, the mask (2) is removed after the application of the capsule layer (5).

Description

The invention relates to a method for producing optoelectronic components for the encapsulation of layers.

An object to be solved is to provide a simple method for encapsulating layers.

This object is achieved inter alia by a method having the features of the independent patent claim. Advantageous embodiments and further developments are the subject of the dependent claims.

In accordance with at least one embodiment of the method, a carrier is provided. The carrier comprises a carrier main side with main directions of extension.

The support preferably has a radiation-permeable, in particular transparent or milky-turbid material, for example glass. Alternatively or additionally, the carrier may comprise or be a semiconductor layer sequence suitable for emitting light. The support may, for example, be a sapphire substrate with a III-V semiconductor layer sequence grown thereon, for example an AlInGaN layer sequence. Furthermore, the carrier may also comprise or consist of a metal.

In accordance with at least one embodiment of the method, a mask is applied to the carrier main side. It has the mask on one of the carrier main side facing mask bottom. Furthermore, the mask has a first mask layer, wherein the first mask layer comprises the mask underside of the mask.

In accordance with at least one embodiment of the method, the mask further comprises a second mask layer. The second mask layer is in particular directly downstream of the first mask layer in the direction away from the mask underside.

The mask may have, in addition to the first and second mask layer, further mask layers, for example a total of three or four or five mask layers.

The first and the second mask layer or each further mask layer may have the same but also different materials. In particular, the first and the second mask layer and also each further mask layer may consist of the same material.

In accordance with at least one embodiment of the method, the mask has one or more apertures. In this case, the at least one breakthrough completely penetrates the mask in a direction perpendicular to the carrier main side. In the area of the breakthrough so a part of the main carrier side is exposed. In this case, the exposed part of the main carrier side is in particular completely exposed, that is, in the region of the opening there are no mask residues on the carrier main side.

In accordance with at least one embodiment of the method, the first mask layer has at least one undercut with respect to the second mask layer in the area of the aperture.

In particular, the undercut of the first mask layer can be present in the entire area of the opening. By subsection is meant, for example, a region of the breakdown in the first mask layer, which is surmounted in the direction away from the carrier main side by the second mask layer.

According to an alternative definition, the undercut of the first mask layer is a defined space region of the opening. In this case, all points in space of the undercut are characterized in particular by the fact that an imaginary straight line perpendicular to the carrier main side can be drawn through each space point of the undercut. If one follows the straight line from the respective point in space in a direction away from the wearer's main side, then the straight line eventually cuts the mask. If one follows the straight line from the point of space in the direction of the carrier main side, then the straight line does not cut the mask. All vertex points of the breakthrough that have these properties are part of the undercut of the first mask layer.

Another alternative definition for the undercut is that the undercut is a contiguous volume of the breakthrough which is partially adjacent to the wearer's main face and completely surmounted by the mask in the direction away from the wearer's wearer's side.

At least one of the three mentioned definitions of the undercut is applicable to the mask according to the specified method. All or more of the definitions may apply.

Considering the cross section of the undercut, wherein the cross-sectional plane cuts through the aperture and is selected perpendicular to the carrier main side, the undercut may for example have a rectangular shape. The undercut can also be a triangular or a have a concave or a convex cross-sectional shape.

In accordance with at least one embodiment of the method, in the region of the second mask layer the aperture has its smallest width and / or smallest diameter.

In accordance with at least one embodiment of the method, a functional material is deposited on the mask in such a way that at least one material structure arises on the main carrier side in the region of the aperture. The material structure is based on the functional material, or is formed from the functional material.

The functional material can furthermore be deposited at least partially on the side of the second mask layer facing away from the carrier main side. At least part of the functional material passes through the mask and deposits on the carrier main side exposed by the opening, so that the material structure is formed.

In accordance with at least one embodiment of the method, at least one capsule layer is applied at least to the material structure. The capsule layer is applied so that it completely covers all exposed before the application of the capsule layer sides and / or surfaces of the material structure. In particular, the material structure therefore has no exposed sides and / or surfaces after the application of the capsule layer.

The capsule layer may deposit on parts of the side of the second mask layer which faces away from the carrier main side. At least part of the capsule layer passes through the breakthrough and deposits on the material structure.

According to at least one embodiment of the method, the mask is removed after the application of the at least one capsule layer. The material structure and the capsule layer applied to the material structure therefore predominantly remain on the carrier. In particular, the mask can be completely removed so that only the material structure and the capsule layer applied to the material structure remain on the carrier.

In at least one embodiment of the method, a carrier, comprising a carrier main side with main directions of extension, is provided. A mask is applied to the carrier main side of the carrier, the mask having a mask underside facing the carrier main side. Furthermore, the mask has a first mask layer which comprises the mask underside. The first mask layer is followed by a second mask layer in the direction away from the mask underside. Furthermore, the mask has at least one opening, which completely penetrates the mask in the direction perpendicular to the carrier main side. Furthermore, the first mask layer has at least one undercut in the area of the opening with respect to the second mask layer, wherein the undercut is a region of the opening which projects beyond the second mask layer in the direction away from the carrier main side. After the mask has been applied to the carrier, a functional material is deposited in such a way that at least one material structure arranged on the carrier main side is produced in the area of the opening. The material structure is based on the functional material. Subsequently, at least one capsule layer is deposited on at least the material structure. The capsule layer is deposited in such a way that, prior to the application of the capsule layer, exposed sides of the material structure are completely covered with the capsule layer. In a further step, the mask is removed after the application of the capsule layer.

The method described here allows the application of a material structure and the subsequent encapsulation of the material structure with only a single mask. The capsule layer serves, for example, to protect the material structure or as a diffusion barrier between the material structure and further layers. Advantageously, the planned tolerances are low in the specified method. Using a single mask layer simplifies the encapsulation process. Furthermore, the method achieves a high quality of overmolding, whereby a thickness of the material structure and / or the capsule layer can be minimized.

The preferred thickness of the material structure is dependent on the function provided for the material structure, for example, the material structure may be formed as a reflection layer and / or current-carrying layer. In particular, therefore, the thickness of the capsule layer can be minimized by the method.

In accordance with at least one embodiment of the method, the application and removal of the mask comprises intermediate steps. In a first step, a first lacquer layer is applied to the carrier main side of the carrier. The first lacquer layer forms the first mask layer of the mask.

In a subsequent step, a second lacquer layer is applied to the side of the first lacquer layer facing away from the main side of the carrier. The second lacquer layer forms the second Mask layer. The second lacquer layer may have at least partially different chemical properties than the first lacquer layer.

After the second lacquer layer has been applied, at least one breakthrough is made in the first and the second lacquer layers by means of a lithographic process, for example by means of an optical lithography process. Preferably, the first and the second lacquer layer have different chemical properties, for example different development rates or different exposure sensitivities, so that the undercut of the first mask layer is formed automatically by the lithography method. For example, the first resist layer is provided with a higher exposure sensitivity than the second resist layer.

After application of the functional material and after application of the capsule layer, the mask is completely removed. The mask can be removed, for example, by means of a suitable solvent, for example via a tape-lift-off method. Alternatively, the mask can also be removed by ashing and / or washing.

According to at least one embodiment of the method, the functional material comprises or consists of an electrically conductive and / or reflective material. For example, the functional material has silver or aluminum or gold. Furthermore, the functional material may comprise a transparent material, for example a transparent conductive material, such as indium tin oxide, ITO for short. Furthermore, the functional material may also comprise or consist of a semiconducting material.

In accordance with at least one embodiment of the method, the at least one capsule layer is applied to protect the material structure. The capsule layer may, for example, comprise a material which does not chemically react with the functional material and / or protects the functional material from chemical reactions with other materials. Furthermore, the capsule layer may also constitute a diffusion barrier for the functional material, for example the capsule layer may protect the functional material from moisture. The capsule layer may, for example, comprise or consist of a metal, such as, for example, platinum or gold. Preferably, the capsule layer comprises or consists of an optically transparent material. The capsule layer may comprise, for example, silicon dioxide or silicon nitride or a metal oxide such as zinc oxide or indium tin oxide. Likewise, the capsule layer may be formed of metal nitrides such as TiWN.

According to at least one embodiment, a further material layer is applied after the application of the at least one capsule layer and before the removal of the mask. Alternatively or additionally, a further layer sequence of further material layers and further capsule layers can also be applied. In particular, the capsule layer then protects the material structure from chemical reactions with the further material layer and / or with the further layer sequence.

In accordance with at least one embodiment of the method, the material structure applied to the carrier main side has a material base surface facing the carrier main side. The material base area is limited by material side surfaces along the main extension directions of the carrier main side. The shape of the material base is determined by the shape of the opening. For example, the shape of the material base can be predetermined by projecting the aperture along a main coating direction onto the carrier main side. The shadow of the mask projected onto the carrier main side through the main coating direction is then preferably not covered or only slightly covered by the material structure.

For the application of the functional material, for example, a material flow of ions and / or atoms and / or molecules and / or clusters, hereinafter generally referred to as particles or particle flow, is directed onto the main carrier side. Each individual particle of the functional material has a direction of flight. The main coating direction results, for example, from the mean direction of flight of all particles of the functional material. For example, the main coating direction is perpendicular to the carrier main side. Alternatively, however, the main coating direction can also extend at an angle of less than 90 °, for example less than 85 °, to the main carrier side.

Furthermore, the particle flow may have a widening in the direction of the carrier main side. In directional deposition methods, for example in thermal evaporation with spherical cap, the expansion of the particle flow is low, for example, avoids the direction of flight of a particle striking the carrier to at least 95% by less than 20 ° from the main coating direction. In low-directed or non-directional processes, for example in the case of evaporation with Knudsen dome or sputtering, English sputtering, or CVD, English Vapor Deposition, the expansion is greater, for example, the direction of flight of a particle striking the support by more than 20 ° of the The main coating direction deviate or the application is isotropic or substantially isotropic.

The extension of the projection of the aperture along the main coating directions, and thus the expansion of the material base area, becomes greater the greater the expansion of the particle flow.

The deposition of the functional material and / or the capsule layer can also take place, for example, in a reactor. A source of the particle stream may then be placed, for example, in the center of the reactor and / or emit particles radially in all directions. The above-mentioned particle flow is then local, to be defined on the space angle occupied by the carrier and / or with regard to the respective material base area. The farther the carrier is away from the radially emitting source, the smaller is the solid angle occupied by the carrier and the smaller is the widening of the particle stream locally defined on the carrier.

In accordance with at least one embodiment of the method, the material structure applied on the carrier main side is formed as a material island. The material island is a contiguous layer of the functional material bounded along the main extension directions. Within the material island, there are preferably no breakthroughs, that is to say no regions of the carrier main side which are free of the functional material and are completely enclosed by the functional material in the main directions of extent. Furthermore, two adjacent islands of material are not interconnected by functional material.

The extent or average extent of the material island along the main extension directions is preferably at most 5 mm, for example ≦ 200 μm, for example ≦ 100 μm. Alternatively or additionally, the expansion of the material island is at least 1 μm, for example ≥ 2 μm, for example ≥ 10 μm. The material base of the material island may, for example, have a round or elliptical or rectangular or hexagonal shape.

In accordance with at least one embodiment of the method, the material structure applied to the carrier main side has a grid-like shape. The material structure thus has at least one region in which the main carrier side is not covered by the functional material, this region being limited in all main directions of extension of functional material. A lattice-like material structure may be, for example, a coherent layer of the functional material, which has, after removal of the mask, regions arranged in matrix-like manner, in which the carrier main side is free of the functional material.

In particular, the material structure can thus be applied in the form of grid lines on the carrier main side.

According to at least one embodiment of the method, prior to removal of the mask, the material structure arranged in the aperture and / or the capsule layer adjoining this material structure are not in direct contact with the first and / or the second mask layer. It is thereby achieved that when the mask is removed, neither the material structure applied on the carrier main side nor the capsule layer located on this material structure is deformed or at least partially destroyed. Thus, the encapsulation of the material structure remains intact and any protection of the material structure by the capsule layer is ensured.

In accordance with at least one embodiment of the method, the first mask layer has a thickness. The thickness of the first mask layer may be greater than a common thickness of the material structure and of the capsule layer located on the material structure. Alternatively, however, the thickness of the first mask layer may also be less than or equal to the common thickness of the material structure and of the capsule layer located on the material structure.

The first mask layer has, for example, a thickness of at least 100 nm, for example ≥ 200 nm, for example ≥ 500 nm. Alternatively or additionally, the thickness of the first mask layer is ≦ 5 μm, for example ≦ 2 μm, for example ≦ 1 μm. The second mask layer typically has a thickness of at least 500 nm, for example ≥ 700 nm, for example ≥ 1 μm. Alternatively or additionally, the thickness of the second mask layer is ≦ 10 μm, for example ≦ 8 μm. In particular, the thickness of the second mask layer may be greater than the thickness of the first mask layer, for example at least twice or at least three times or at least four times as thick.

In accordance with at least one embodiment of the method, the undercut has a depth or average depth or maximum depth or minimum depth parallel to the main extension directions, which is ≦ 50 μm, for example ≦ 30 μm, for example ≦ 10 μm. Alternatively or additionally, the depth of the undercut is ≥ 1 μm, for example ≥ 2 μm, for example ≥ 5 μm. Preferably, the depth of the undercut is greater than the thickness of the first mask layer, for example three times or five times or ten times larger.

In accordance with at least one embodiment of the method, the material structure has a thickness or average thickness or maximum thickness or minimum thickness of ≥ 10 nm, for example ≥ 50 nm, for example ≥ 150 nm. Alternatively or additionally, the material structure has a thickness of ≦ 5 μm, for example ≦ 500 nm, for example ≤ 200 nm.

In accordance with at least one embodiment of the method, the capsule layer has an average thickness of at least 1 nm, for example ≥ 10 nm, for example ≥ 50 nm. Alternatively or additionally, the average thickness of the capsule layer is ≦ 10 μm or ≦ 500 nm or ≦ 200 nm. The local thickness of the capsule layer, ie the thickness at any point of the capsule layer, preferably deviates from the average thickness of the capsule layer by less than 50% ,

By a very homogeneous thickness of the capsule layer, a secure encapsulation of the material structure is achieved even with a small thickness of the capsule layer.

In accordance with at least one embodiment of the method, the capsule layer located on the material structure has protrusions with respect to the material structure in all main directions of extension. The supernatants result, for example, from the thickness of the applied on the material side surfaces capsule layer. The supernatants of the capsule layer are preferably ≦ 10 μm or ≦ 500 nm or ≦ 200 nm. Alternatively or additionally, the supernatants are ≥ 1 nm or ≥ 10 nm or ≥ 50 nm.

In accordance with at least one embodiment of the method, the functional material is deposited in an at least locally directed method. By the directed method, the material structure on the carrier main side is preferably formed sharp-edged. The material side surfaces include, for example, an angle of at least 70 ° with the material base. The subsequent deposition of the capsule layer can be carried out, for example, via a slightly directed or non-directional method.

For the directed method for applying the functional material, it is possible, for example, to use thermal evaporation, for example with a spherical-cap reactor, as the deposition process. The low-directed or non-directional application of the capsule layer can be carried out, for example, by thermal evaporation with a Knudsen calotte or sputtering or via a CVD, English Chemical Vapor Deposition, process.

By the above definition, a directional deposition process is a process in which the direction of flight of a particle striking the support deviates, for example, by at least 95% by less than 20 ° from the main coating direction. For example, in a low-profile deposition process, the direction of flight of a particle impacting the support may be more than 20 ° from the main coating direction. By undirected method, for example, a method may be meant in which particles are applied as isotropically as possible and as homogeneously as possible on the carrier. This allows, for example, an effective deposition of the capsule layer on the material side surfaces of the material structure. In non-directional processes, the directions of flight of individual particles can deviate greatly, for example, more than 90 ° or more than 150 °, from the main coating direction. It may then be difficult to specify a specific main coating direction at all. Non-directional methods can be, for example, sputtering or CVD.

In accordance with at least one embodiment of the method, the functional material is deposited in a slightly directed method. Due to the less directed method, the material structure preferably has flattened material side surfaces. The material side surfaces include, for example, with the material base an angle of at most 70 °. In the subsequent application of the capsule layer, for example, a non-directional method can be used.

According to at least one embodiment of the method, further layers are applied to the carrier main side after the deposition of the capsule layer or after removal of the mask. Additionally or alternatively, the carrier can also be further structured.

For example, after removal of the mask, further layers can be applied to the support in an ALD process, in particular atomic layer deposition, in particular with ozone support. Alternatively or additionally, the support can be further structured, for example, by wet-chemical or dry-chemical etching with chlorine. By encapsulating the material structure is preferably protected from chemical reactions with, for example, ozone or chlorine.

In accordance with at least one embodiment of the method, the mask has a plurality of apertures arranged in the manner of a matrix. In this way, a plurality of encapsulated material structures can be produced in one step during the deposition of the functional material and / or the capsule layer. This may be advantageous, for example, for the simultaneous production of multiple chips on a sapphire or silicon wafer.

In accordance with at least one embodiment of the method, the distance between two separate material structures arranged on the carrier and adjacent one another is ≦ 100 μm, for example ≦ 50 μm, for example ≦ 20 μm.

The distance between two material structures can be understood as the shortest distance between any two points located on two adjacent islands of material.

By applying the material structures and the capsule layer with a single mask tolerances to be considered can be kept low. This makes it possible to produce material structures with a small distance from each other. Furthermore, the method described here makes possible an exact and self-aligned bringing together of the material structure and the capsule layer.

In the following, a method described here for producing optoelectronic components for the encapsulation of layers will be explained in more detail with reference to the drawings on the basis of exemplary embodiments. The same reference numerals indicate the same elements in the individual figures. However, there are no scale relationships shown, but individual elements can be shown exaggerated for better understanding.

Show it:

1a to 1e schematic sectional views of exemplary embodiments of the method described here,

2a to 2c schematic cross-sectional views of the method described here using different degrees of deposition processes,

3a to 3c schematic sectional views of different embodiments of the mask described here,

4a to 4b individual steps for producing the mask from at least two paint layers,

5a to 5b schematic plan view of a mask with multiple openings or a coherent lattice-like breakthrough.

In 1a is shown in a sectional view, a first step of the method. A provided carrier 1 includes a carrier main page 10 with main directions of extension T. On the carrier main side 10 becomes a mask 2 applied. The mask 2 includes one of the main carrier side 10 facing mask underside 20 , Further, the mask faces 2 a first mask layer 21 on top of the mask bottom 20 includes. The mask layer 21 is heading off the mask base 20 a second mask layer 22 downstream.

1b shows a further step of the method according to which the mask 2 on the carrier main page 10 was applied. In this embodiment, the mask 2 a breakthrough 200 on, parts of the vehicle's main side 10 exposes. The second mask layer 22 here includes the area of the breakthrough 200 at which the diameter of the breakthrough 200 is lowest. Further, the breakthrough 200 designed so that the first mask layer 21 undercuts 201 with respect to the second mask layer. In the undercuts 201 becomes a part of the breakthrough 200 towards the vehicle's main side 10 from the second mask layer 22 surmounted. In the sectional view according to 1b show the undercuts 201 rectangular cross-sectional shapes on.

The height of the undercuts defines a thickness H1 of the first mask layer 21 , The first mask layer 21 has, for example, a thickness H1 of 800 nm. The second mask layer 22 has, for example, a thickness H2 of 5 μm.

In the direction parallel to the main directions of extension T have the undercuts 201 a depth U on. The depth U of the undercuts is for example 5 microns.

The one through the breakthrough 200 uncovered part of the vehicle's main side 10 For example, has an extent along the main extension directions T of 80 microns.

1c shows a further step of the method. On the mask 2 , in particular to the breakthrough 200 uncovered vehicle main page 10 , becomes a functional material 4 applied. On the vehicle main page 10 This creates a material structure 41 , The material structure 41 For example, a material island 41 be. The material structure 41 has a material footprint 410 on. Along the main extension directions T is the material footprint 410 through material side surfaces 411 limited.

In the in 1c illustrated embodiment, the functional material 4 For example, by a directed method, for example, by thermal evaporation with a spherical cap as a deposition process applied. The material structure 41 is thus formed sharp-edged, that is, the material side surfaces 411 close with the material basis 410 an angle of at least 70 °.

The shape of the material base 410 is through a projection of the breakthrough 200 along a main coating direction M on the carrier main side 10 specified. The main coating direction M results, for example, from a mean direction of flight of all particles of the functional material 4 by means of one on the carrier main side 10 directed particle flow can be applied. For example, particles may include ions and / or atoms and / or molecules and / or clusters of the functional material 4 be understood. In 1c the main coating direction M is perpendicular or nearly perpendicular to the carrier main side 10 ,

In the in 1c given embodiment, the shape of the material base 410 through the shape of the breakthrough 200 in the area of the second mask layer 22 given, so that in particular a width of the opening 200 in the area of the second mask layer 22 a width of the material base 410 equivalent. Further, the carrier main side 10 in the area of undercuts 201 free or almost free of the functional material 4 , The width or average width of the material base 411 is, for example, 70 μm, an average thickness of the material structure 41 is for example 500 nm.

In 1d an embodiment is shown for a further step of the method. A capsule layer 5 gets on the functional material 4 especially on the material structure 41 or the material island 41 applied. The capsule layer 5 It is deposited via a little directional or non-directional method, such as thermal evaporation with a Knudsen dome or sputtering or CVD, English Chemical Vapor Deposition, or ALD, English atomic layer deposition. This is where the capsule layer settles 5 on all previously exposed pages of the material structure 41 off, leaving the material structure 41 completely with the capsule layer 5 is covered. The capsule layer 5 has an average thickness of 100 nm, for example.

1e shows the on the carrier 1 arranged material structure 41 with capsule layer 5 after completely removing the mask 2 , The capsule layer 5 encloses the material structure 41 Completely. By using a single mask 2 for applying the functional material 4 and the capsule layer 5 a high quality overshoot is achieved with low scheduling tolerances. This enables a minimization of the thickness of the capsule layer 5 ,

In 1e points to the material structure 41 located capsule layer 5 In all main directions of extension T protrusions with respect to the material structure. The supernatants are, for example, by the thickness of the capsule layer 5 on the material side surfaces 411 determined and are for example 80 nm wide.

2a shows similar to 1d an embodiment of a method step in which the capsule layer 5 already on the functional material 4 was applied. In contrast to 1d has the capsule layer 5 in 2a Runners on, which are in the area of the material side surfaces 411 are arranged. These spurs may arise, for example, when the capsule layer 5 is applied in a low-profile process. The foothills cover an additional portion of the vehicle's main side 10 and may, for example, have an extent along the main extension direction T of at least 1 μm.

2 B shows a further embodiment analogous to 2a , In contrast to 2a was in the embodiment of 2 B the functional material 4 applied by a low-profile method, for example by thermal evaporation with Knudsen dome. By the little-directed method, the material structure 41 a flattened shape. The material side surfaces 411 close for example with the material base 410 an angle of 40 °.

The capsule layer 5 in turn has been applied by a low-profile or non-directional method, so that all prior to application of the capsule layer 5 exposed surfaces of the material structure 41 from the capsule layer 5 completely covered.

In the embodiment according to 2c became the functional material 4 and the capsule layer 5 for example as well as in 2 B applied. Additionally is in 2c yet another layer of material 6 , For example, via a non-directional method applied. At the material layer 6 it may be a single material or even a layer sequence of several further material layers and further capsule layers. For example, in FIG 2c the functional material 4 Aluminum on, the capsule layer 5 may, for example, have platinum. Furthermore, the further material layer can also be used 6 have a metal. The capsule layer 5 For example, it acts as a diffusion barrier and prevents a reaction between the material structure 41 and the further material layer 6 ,

In the embodiment according to 3a is a mask 2 with a breakthrough 200 shown, whose cross-sectional shape of the cross-sectional shape of the apertures 200 in the 1a to 2 B differs. The cross - sectional shape shown here breakthrough 200 is shown less idealized than that in the previous embodiments. In particular, the breakthrough shows 200 in the area of the first mask layer 21 and in the region of the second mask layer 22 rounded side surfaces on. Such side surfaces may arise, for example, in a lithographic process, wherein the first mask layer 21 for example, a higher exposure sensitivity than the second mask layer 22 having.

The second mask layer comprises the area of the aperture 200 at which the breakthrough 200 having the smallest diameter. Furthermore, the first mask layer 21 also undercuts here 201 with respect to the second mask layer 22 on.

The delineations of the undercuts 201 along the main directions of extension T are each about two dashed, perpendicular to the carrier main page 10 characterized by running lines. The position of a dashed line in each case is over a point of the first mask layer 21 Are defined. This point is on the breakthrough 200 adjacent side surface of the first mask layer 21 and is the closest to the carrier main page 10 , The position of each other dashed line becomes over a point of the second mask layer 22 Are defined. This point is a point of the second mask layer 22 at which the breakthrough 200 having the smallest diameter.

Between, for example, the two leftmost dashed, perpendicular to the carrier main page 10 running lines, so is the undercut 201 in the left area of the breakthrough 200 Are defined. The distance between the two dashed lines gives the depth U of the undercut 201 in front. Analogous to this is the demarcation of the undercut 201 in the right area of the breakthrough 200 over the two furthest right, dashed, perpendicular to the carrier main page 10 predetermined lines.

For all space points in the undercuts 201 It is also true that a straight line can be drawn through each of these points in space, which is perpendicular to the main carrier side 10 runs. If you follow the straight line from the point of space in the direction away from the main beam side 10 so the line cuts the mask 2 , If you follow the straight line from the point of space towards the main beam side 10 , there is no intersection with the mask 2 , It also holds that in the area of undercuts 201 the breakthrough 200 towards the vehicle's main side 10 from the second mask layer 22 is towered over.

Left next to the left undercut 201 or right next to the right undercut 201 shows the breakthrough 200 a concave or convex flow area 202 on. The flow areas 202 may be advantageous in applying the capsule layer 5 on the material structure 41 Act. When applied, the particles of the capsule layer 5 through the flow areas 202 be redirected and thus more effective or more homogeneous on the material side surfaces 411 the material structure 41 deposit.

In 3b is another possible cross-sectional shape of the breakthrough 200 specified. In the area of the first mask layer 21 shows the breakthrough 200 For example, the shape of one in the direction away from the carrier 1 tapered trapezoid. In the area of the second mask layer 22 shows the breakthrough 200 the shape of one moving away from the vehicle 1 widening trapezes. The second mask layer 22 again includes the area of breakthrough 200 with the smallest diameter. The depths U of the undercuts 201 are like in 3a over the dashed, perpendicular to the carrier main page 10 defined by running lines. The position of these lines along the main extension directions T is also as in FIG 3a Are defined.

The undercuts 201 the first mask layer 21 also satisfy the same definition as the undercuts 201 in 3a that is, each perpendicular to the carrier main page 10 straight line passing through any point in space of the undercuts 201 cuts the mask as seen from the point of view of space 2 towards the vehicle's main side. If you follow the straight line from the point of space towards the main beam side 10 so the line cuts the mask 2 Not. That means, in particular, that the breakthrough 200 in the area of undercuts 201 towards the vehicle's main side 10 from the second mask layer 22 is towered over.

In the embodiment according to 3c has the breakthrough 200 the cross-sectional shape of one moving away from the wearer 1 tapered trapezoid. The thickness of the first mask layer H1 is greater than the thickness of the second mask layer H2. However, in the exemplary embodiment shown here, there is no clear boundary between the first mask layer 21 and the second mask layer 22 given, on the one hand, the first mask layer 21 and the second mask layer 22 have the same materials or consist of the same materials and because, on the other hand, the breakthrough constantly tapers away in the direction away from the carrier main page. In particular, therefore, the ratio of the thickness H1 of the first mask layer 21 to the thickness H2 of the second mask layer 22 in 3a be chosen freely. For example, the second mask layer 22 a very small thickness H2, for example, a thickness H2 of only a few nanometers, are assigned, so that the mask 2 almost exclusively from the first mask layer 21 is formed. The second mask layer 22 again includes the area of breakthrough 200 which has the smallest diameter.

The undercuts 201 extend in the main directions of extension T turn as in 3a defined, ie within each two dashed, perpendicular to the carrier main page 10 running lines with fixed positions. In particular, the undercuts are sufficient 201 thus again the definition, according to which through every point of space in the area of an undercut 201 an imaginary straight line perpendicular to the main carrier side 10 can be pulled. If one follows this straight line from the point of space in the direction of the carrier main side 10 so the line cuts the mask 2 not, one follows the straight line from the point of space in the direction away from the carrier main side 10 so the line cuts the mask 2 ,

In the embodiment according to 4a is a sectional view of a manufacturing method of the mask 2 specified. In a first step, the first mask layer is in the form of a first lacquer layer 21b on the carrier main page 10 applied. Subsequently, on the carrier main page 10 opposite side of the first mask layer 21 the second mask layer 22 in the form of a second lacquer layer 22b applied. The second mask layer 22 thus has, for example, different chemical properties than the first mask layer 21 In particular, the first and the second mask layer can therefore have different materials or consist of different materials.

In the embodiment according to 4b will be a breakthrough 200 in the first coat of paint 21b and the second coat of paint 22b brought in. The breakthrough 200 can be introduced, for example, in one step by means of an optical lithography process. Preferably, in this case, the first lacquer layer 21b for example, a higher exposure sensitivity than the second resist layer 22b , Due to the different exposure sensitivities, in the area of the first lacquer layer 21b automatically undercuts 201 train so that in the area of the undercut 201 the second coat of paint 22b the first coat of paint 21b surmounted.

By applying a first and a second lacquer layer, it is particularly easy to produce a mask for the encapsulation of layers in accordance with the method described here.

In 5a is a possible embodiment of a mask 2 with several breakthroughs 200 specified. At the same time the mask becomes 2 considered in plan view perpendicular to the main extension directions T. Mainly so is one of the main carrier side 10 To see opposite side of the second mask layer, which is shown as a dotted area.

The breakthroughs 200 are matrix-like in the mask 2 arranged. The breakthroughs 200 are shown as white areas. Furthermore, the breakthroughs have 200 a rectangular cross-sectional shape. For example, the cross-sectional shape of each breakthrough 200 but also be round or triangular or hexagonal.

The solid rectangles show the cross-sectional shape of the openings 200 in the area of the second mask layer 22 , The dashed rectangular shapes indicate the breakthrough shapes in the region of the first mask layer 21 on, in 5a through the second mask layer 22 is covered. In particular, the dashed rectangles are larger than the solid rectangles and completely enclose the solid rectangles. This means that throughout the entire range of each breakthrough 200 an undercut 201 the first mask layer 21 with respect to the second mask layer 22 is trained.

In the 5a shown mask with a plurality of openings 200 can be used to create and encapsulate a plurality of islands of material. The use or the introduction of a plurality of breakthroughs 200 in a mask 2 is possible for all embodiments shown.

Furthermore, it is possible that the breakthrough 200 in the mask 2 is introduced in the form of a grid. A considered in plan view corresponding embodiment is shown in 5b shown. 5b differs from 5a to the effect that in 5b a continuous breakthrough 200 in the mask 2 is introduced. The continuous breakthrough 200 encloses areas of the mask 2 so that the breakthrough 200 is grid-like in plan view.

The invention described here is not limited by the description based on the embodiments. 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 stated in the patent claims or exemplary embodiments.

Claims (16)

Method for producing optoelectronic components for the encapsulation of layers, comprising the steps: - providing a carrier ( 1 ), comprising a carrier main side ( 10 ) with main directions of extension (T), - application of a mask ( 2 ) on the carrier main side ( 10 ), whereby the mask ( 2 ) a) one of the carrier main side ( 10 ) facing mask base ( 20 ), b) one the mask underside ( 20 ) comprehensive first mask layer ( 21 ), c) one of the first mask layer ( 21 ) in the direction away from the mask underside ( 20 ) subordinate second mask layer ( 22 ), d) and at least one mask ( 2 ) completely in the direction perpendicular to the carrier main side ( 10 ) penetrating breakthrough ( 200 ), wherein the first mask layer ( 21 ) in the area of the breakthrough ( 200 ) at least one undercut ( 201 ) with respect to the second mask layer ( 22 ), wherein the undercut ( 201 ) an area of the breakthrough ( 200 ), which is in the direction away from the carrier main side ( 10 ) from the second mask layer ( 22 ), - deposition of a functional material ( 4 ), so that in the area of the breakthrough ( 200 ) at least one on the carrier main side ( 10 ) arranged material structure ( 41 ) is created on the functional material ( 4 ), - deposition of at least one capsule layer ( 5 ) on at least the material structure ( 41 ), so that before the application of the capsule layer ( 5 ) exposed sides of the material structure ( 41 ) completely with the capsule layer ( 5 ), and - removing the mask ( 2 ). Method according to claim 1, wherein for the application and removal of the mask ( 2 ) the following intermediate steps are carried out: application of a first lacquer layer ( 21b ) on the carrier main side ( 10 ), whereby through the first lacquer layer ( 21b ) the first mask layer ( 21 ), - applying a second lacquer layer ( 22b ) on one of the carrier main side ( 10 ) facing away from the first layer of lacquer ( 21b ), whereby through the second lacquer layer ( 22b ) the second mask layer ( 22 ), and wherein the second lacquer layer ( 22b ) at least partially different chemical properties than the first lacquer layer ( 22a ), - introduction of the at least one breakthrough ( 200 ) in the first and second lacquer layer ( 21b . 22b ) by means of a lithography process, so that the at least one undercut ( 201 ) is formed by the lithography process, - complete removal of the mask ( 2 ) after application of the material structure ( 41 ) and the capsule layer ( 5 ). Method according to one of the preceding claims, wherein after the application of the capsule layer ( 5 ) and before removing the mask ( 2 ) another layer of material ( 6 ) is applied, wherein the functional material ( 4 ) Aluminum and wherein the capsule layer ( 5 ) Has platinum. Method according to claim 1 or 2, wherein the functional material ( 4 ) Silver and wherein the capsule layer ( 5 ) SiO ₂ . Method according to one of the preceding claims, wherein the material structure ( 41 ) one of the carrier main side ( 10 ) facing material surface ( 410 ), wherein the material base ( 410 ) through material side surfaces ( 411 ) along the main extension directions (T) is limited, and wherein the shape of the material base ( 410 ) by a projection of the breakthrough ( 200 ) along a main coating direction (M) on the carrier main side ( 10 ) is given. Method according to one of the preceding claims, wherein the material structure ( 41 ) as a material island ( 41 ) is formed. Method according to one of the preceding claims, wherein the material structure ( 41 ) has a grid-like shape. Method according to one of the preceding claims, wherein prior to removal of the mask ( 2 ) the material structure ( 41 ) and / or to the material structure ( 41 ) adjacent capsule layer ( 5 ) in no direct contact with the first mask layer ( 21 ) and / or the second mask layer ( 22 ) are located. Method according to one of the preceding claims, wherein the first mask layer ( 21 ) has a thickness (H1) between 100 nm and 5 μm, and wherein the thickness (H1) of the first mask layer ( 21 ) is greater than a common thickness of the material structure ( 41 ) and the capsule layer ( 5 ). Method according to at least claim 6, wherein the material island ( 41 ) Has expansions along the main extension directions (T) between 1 μm and 5 mm, the undercut ( 201 ) has a depth (U) parallel to the main directions of extension (T) between 1 μm and 20 μm, and wherein the capsule layer ( 5 ) has an average thickness between 1 nm and 2 μm, wherein a local thickness of the capsule layer ( 5 ) of the average thickness of the capsule layer ( 5 ) differs by less than 50%. Method according to one of the preceding claims, wherein the functional material ( 4 ) is deposited in a directional process, so that a sharp-edged material structure ( 41 ) arises, in which the material side surfaces ( 411 ) with the material base ( 410 ) enclose an angle of at least 70 °, and wherein the capsule layer ( 5 ) is deposited in a non-directional or non-directional process. Method according to one of the preceding claims, wherein the functional material ( 4 ) is deposited in a low-profile process so that a flattened material structure ( 41 ) arises, in which the material side surfaces ( 411 ) with the carrier main side ( 10 ) facing material surface ( 410 ) have an angle between 0 ° and 70 °, and wherein the capsule layer ( 5 ) is deposited in a non-directional process. Method according to one of the preceding claims, wherein after the deposition of the capsule layer ( 5 ) or after removing the mask ( 2 ) additional layers on the carrier main side ( 10 ) or the carrier ( 1 ) is further structured. Method according to one of the preceding claims, wherein the carrier has a semiconductor layer sequence suitable for radiation emission. Method according to one of the preceding claims, wherein the mask ( 2 ) a plurality of matrix-like openings ( 200 ), so that when depositing the functional material ( 4 ) and the capsule layer ( 5 ) a plurality of encapsulated material structures ( 41 ) arises. The method of claim 15, wherein a distance between two material structures ( 41 ) is less than 20 microns, below the distance the shortest distance between two material structures ( 41 ), which are not compatible with the functional material ( 4 ) is understood.

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