Laser bar chip and method for producing a laser bar chip

Abstract

The invention relates to laser bar chip having at least one first laser diode and a second laser diode. The first laser diode and the second laser diode have respective waveguide structures. The laser bar chip has a first cathode contact which is electrically conductively connected to the first laser diode and a second cathode contact which is electrically conductively connected to the second laser diode.

Description

[0001] LASER BAR CHIP AND METHOD FOR PRODUCING ONE

[0002] LASER BAR CHIPS

[0003] DESCRIPTION

[0004] The present invention relates to a laser bar chip and a method for producing a laser bar chip.

[0005] Laser bar chips with a plurality of laser diodes are known in the art. In known laser bar chips, the laser diodes have a common cathode.

[0006] One object of the present invention is to provide a laser bar chip. Another object of the present invention is to specify a method for producing a laser bar chip. These objects are achieved by a laser bar chip and by a method for producing a laser bar chip having the features of the independent claims. Various developments are specified in the dependent claims.

[0007] A laser bar chip has at least a first laser diode and a second laser diode. The first laser diode and the second laser diode each have a waveguide structure. The laser bar chip has a first cathode contact, which is electrically conductively connected to the first laser diode, and a second cathode contact, which is electrically conductively connected to the second laser diode.

[0008] In this laser bar chip, the first laser diode and the second laser diode can be controlled independently of each other via the first cathode contact and the second cathode contact. Control via the cathode contacts enables the use of n-channel FETs to switch the current flow through the laser diodes. This can advantageously enable very fast switching. A smaller design is also feasible, since n-channel FETs can be made smaller than comparable p-channel FETs.

[0009] In one embodiment of the laser bar chip, it has a third laser diode. The second cathode contact is electrically connected to the third laser diode. This advantageously makes it possible to form the laser bar chip with a number of laser diodes that is greater than the number of cathode contacts. As a result, the laser bar chip can advantageously be formed with a large number of laser diodes, even while maintaining a required minimum size of the cathode contacts.

[0010] In one embodiment of the laser bar chip, it has a first anode contact that is electrically connected to the first laser diode. This makes it possible to supply the first laser diode with electrical voltage and electrical current via the first anode contact and the first cathode contact.

[0011] In one embodiment of the laser bar chip, the first anode contact is electrically conductively connected to the second laser diode. Advantageously, only one anode contact is required to supply the first laser diode and the second laser diode, which makes it possible to design the laser bar chip with compact dimensions even while maintaining a minimum size for the first anode contact. The first cathode contact and the second cathode contact enable individual control of the first laser diode and the second laser diode, despite the first anode contact being shared by the first laser diode and the second laser diode.

[0012] In one embodiment of the laser bar chip, it has a second anode contact that is electrically connected to the third laser diode. This makes it possible to control the second laser diode and the third laser diode independently of one another, even if the second cathode contact is electrically connected to the second laser diode and the third laser diode.

[0013] In one embodiment of the laser bar chip, an electrically non-conductive passivation is arranged on the waveguide structure of the first laser diode. In the region of the first anode contact, the passivation is open, so that the first anode contact is electrically conductively connected to the first laser diode. The second anode contact is electrically insulated from the first laser diode by the passivation. This advantageously makes it possible to arrange the first anode contact and the second anode contact with a flexibly predeterminable geometry on a surface of the laser bar chip while still ensuring individual contacting of individual laser diodes by individual anode contacts.

[0014] In one embodiment of the laser bar chip, the first anode contact is arranged on a first surface of the laser bar chip. The first cathode contact and the second cathode contact are arranged on a second surface of the laser bar chip. This advantageously enables utilization of the space available on the first surface and the second surface of the laser bar chip, so that the laser bar chip can be formed with a minimum overall size while maximizing the size of the anode contacts and the cathode contacts.

[0015] In one embodiment of the laser bar chip, a rewiring structure is formed on the second surface of the laser bar chip. This rewiring structure can enable an even more flexible design of the geometry of the cathode contacts. Furthermore, the rewiring structure can enable the rewiring and combination of individual cathode contacts.

[0016] In one embodiment of the laser bar chip, the first anode contact, the first cathode contact, and the second cathode contact are arranged together on a first surface of the laser bar chip. This advantageously enables complete electrical contacting of the laser bar chip via the first surface.

[0017] In one embodiment of the laser bar chip, a rewiring structure is formed on the first surface of the laser bar chip. This rewiring structure can enable an even more flexible geometry of the electrical contact surfaces arranged on the first surface. The rewiring structure can also enable rewiring and electrical combination of individual electrical contact surfaces.

[0018] In one embodiment of the laser bar chip, an epitaxial layer of the laser bar chip has an electrically non-conductive interruption between the first laser diode and the second laser diode. This allows for cathode-side decoupling of the first laser diode and the second laser diode.

[0019] In one embodiment of the laser bar chip, the epitaxial layer is arranged on an electrically conductive substrate. A first section of the substrate and a second section of the substrate are electrically insulated from one another by an electrically non-conductive region. The first cathode contact is electrically conductively connected to the first laser diode via the first section of the substrate. The second cathode contact is electrically conductively connected to the second laser diode via the second section of the substrate. The division of the substrate into the first section and the second section enables cathode-side decoupling of the first laser diode and the second laser diode and individual cathode-side contacting of the first laser diode and the second laser diode.

[0020] In another embodiment of the laser bar chip, the epitaxial layer is arranged on an electrically non-conductive substrate. The substrate has an electrically conductive first via and an electrically conductive second via. The first cathode contact is electrically conductively connected to the first laser diode via the first via. The second cathode contact is electrically conductively connected to the second laser diode via the second via. The first via and the second via thus enable individual cathode-side contacting of the first laser diode and the second laser diode of the laser bar chip.

[0021] A method for producing a laser bar chip comprises steps of providing a substrate having an epitaxial layer arranged on a top side, forming at least a first laser diode and a second laser diode in the epitaxial layer, wherein the first laser diode and the second laser diode each have a waveguide structure, and forming a first cathode contact which is electrically conductively connected to the first laser diode and a second cathode contact which is electrically conductively connected to the second laser diode.

[0022] Advantageously, this method enables the production of a laser bar chip with at least two laser diodes that are independently controlled via individual cathode contacts. N-channel FETs can advantageously be used for control, which can enable fast control.

[0023] In one embodiment of the method, this comprises a further step of creating an electrically non-conductive interruption in the epitaxial layer between the first laser diode and the second laser diode. This advantageously achieves a cathode-side decoupling of the first laser diode and the second laser diode.

[0024] In one embodiment of the method, the substrate is electrically non-conductive. The method comprises a further step of creating an electrically conductive first via and an electrically conductive second via in the substrate. The first cathode contact is electrically conductively connected to the first laser diode via the first via. The second cathode contact is electrically conductively connected to the second laser diode via the second via. The vias created in this way thus enable individual cathode-side contacting of the first laser diode and the second laser diode.

[0025] In one embodiment of the method, the substrate is electrically conductive. The method comprises a further step of creating an electrically non-conductive region in the substrate in order to electrically insulate a first section of the substrate and a second section of the substrate from one another. The first cathode contact is electrically conductively connected to the first laser diode via the first section of the substrate. The second cathode contact is electrically conductively connected to the second laser diode via the second section of the substrate. In this variant of the method, the division of the substrate into the first section and the second section enables individual cathode-side contacting of the first laser diode and the second laser diode.

[0026] In one embodiment of the method, the electrically non-conductive interruption in the epitaxial layer and the electrically non-conductive region in the substrate are created jointly by a FIB process (focused ion beam irradiation). This advantageously enables precise formation of the electrically non-conductive interruption in the epitaxial layer and the electrically non-conductive region in the substrate.

[0027] In one embodiment of the method, the electrically non-conductive interruption is created by etching a trench in the epitaxial layer. Advantageously, this method enables a reliable and precise formation of the electrically non-conductive interruption in the epitaxial layer.

[0028] In one embodiment of the method, the trench is filled with an electrically non-conductive material. This advantageously allows for subsequent covering of the trench filled with the electrically non-conductive material with additional material.

[0029] The above-described properties, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understandable in connection with the following description of the embodiments, which are explained in more detail in connection with the drawings. In each case, a schematic representation shows

[0030] Figure 1 is a view of a first surface of a laser bar chip with a plurality of anode contacts;

[0031] Figure 2 is a view of a second surface of the laser bar chip with a plurality of cathode contacts;

[0032] Figure 3 is a sectional side view of a variant of a laser bar chip;

[0033] Figure 4 is a partially transparent perspective view of this variant of the laser bar chip;

[0034] Figure 5 is a sectional side view of another variant of a laser bar chip;

[0035] Figure 6 is a sectional side view of another variant of a laser bar chip;

[0036] Figure 7 is a sectional side view of another variant of a laser bar chip; Figure 8 is a sectional side view of another variant of a laser bar chip;

[0037] Figure 9 is a sectional side view of another variant of a laser bar chip; and

[0038] Figure 10 is a sectional side view of another variant of a laser bar chip.

[0039] Figure 1 shows a schematic perspective view of a first surface 101 of a laser bar chip 100. Figure 2 shows a schematic perspective view of a second surface 102 of the laser bar chip 100 opposite the first surface 101.

[0040] The laser bar chip 100 has a cuboidal basic shape with a length 110 and a width 120. The length 110 can be, for example, 600 pm and can be predetermined, for example, by a minimum length of waveguide structures of laser diodes of the laser bar chip 100. The width 120 of the laser bar chip 100 can be, for example, 125 pm.

[0041] The laser bar chip 100 has a plurality of integrated laser diodes 500. In the example shown in Figures 1 and 2, the laser bar chip 100 has a first laser diode 500, 510, a second laser diode 500, 520, a third laser diode 500, 530, a fourth laser diode 500, 540, a fifth laser diode 500, 550, a sixth laser diode 500, 560, a seventh laser diode 500, 570, and an eighth laser diode 500, 580, which are arranged next to one another in this order. However, the laser bar chip 100 can also be formed with a different number of laser diodes 500.

[0042] Each of the laser diodes 500 has a waveguide structure 600, which can also be referred to as a ridge. Therefore, the laser bar chip 100 can also be referred to as a multi-ridge laser chip. In the example shown, the waveguide structures 600 of the laser diodes 500 are oriented parallel to one another and parallel to the edges of the laser bar chip 100, which edges have a length 110, and are arranged on the first surface 101 of the laser bar chip 100. However, this is not absolutely necessary. In this case, the waveguide structures 600 of the laser diodes 500 in the example shown are not distributed over the entire width 120 of the laser bar chip 100, but are arranged closer to one side of the laser bar chip 100. However, this can also be designed differently. At one longitudinal end of the waveguide structures 600, the laser diodes 500 each have an output facet 610, at which a laser beam emerges during operation of the respective laser diode 500.

[0043] A first anode contact 810, a second anode contact 820, a third anode contact 830, and a fourth anode contact 840 are arranged on the first surface 101 of the laser bar chip 100. In other variants of the laser bar chip 100, fewer or more than four anode contacts 810, 820, 830, 840 can be provided. The anode contacts 810, 820, 830, 840 are provided for electrically contacting the laser bar chip 100, for example, for contacting by bonding or soldering. The anode contacts 810, 820, 830, 840 comprise a metal suitable for electrical contacting, for example, gold. It is expedient if the anode contacts 810, 820, 830, 840 are each approximately the same size and jointly utilize the space available on the first surface 101 of the laser bar chip 100 as fully as possible. For example, each of the anode contacts 810, 820, 830, 840 can have a size of 134 pm by 105 pm.

[0044] A first cathode contact 710 and a second cathode contact 720 are arranged on the second surface 102 of the laser bar chip 100. In other variants of the laser bar chip 100, fewer or more than two cathode contacts 710, 720 may be provided. The cathode contacts 710, 720 are also provided for electrically contacting the laser bar chip 100 and comprise a metal suitable for electrical contacting, for example, gold. It is expedient if the cathode contacts 710, 720 have approximately the same size and together utilize the space available on the second surface 102 as fully as possible.

[0045] The anode contacts 810, 820, 830, 840 are provided for the anode-side contacting of the laser diodes 500. The cathode contacts 710, 720 are provided for the cathode-side electrical contacting of the laser diodes 500. It is expedient if each laser diode 500 can be individually addressed by a combination of a cathode contact 710, 720 and an anode contact 810, 820, 830, 840. For this purpose, for example, the first cathode contact 710 can be electrically connected to the first laser diode 500, 510, the third laser diode 500, 530, the fifth laser diode 500, 550, and the seventh laser diode 500, 570. The second cathode contact 720 is then electrically connected to the second laser diode 500, 520, the fourth laser diode 500, 540, the sixth laser diode 500, 560 and the eighth laser diode 500, 580.In this case, the first anode contact 810 can be connected to the first laser diode 500, 510 and the second laser diode 500, 520, while the second anode contact 820 is connected to the third laser diode 500, 530 and the fourth laser diode 500, 540, the third anode contact 830 is connected to the fifth laser diode 500, 550 and the sixth laser diode 500, 560, and the fourth anode contact 840 is connected to the seventh laser diode 500, 570 and the eighth laser diode 500, 580. Of course, other interconnections are also possible.

[0046] The anode contacts 810, 820, 830, 840 can be controlled via p-channel FETs, for example. The cathode contacts 710, 720 can be controlled via n-channel FETs, for example.

[0047] Various variants of the laser bar chip 100 are described below. The description is partially limited to aspects in which the respective variant of the laser bar chip 100 differs from the previously described variants of the laser bar chip 100. Furthermore, the preceding explanations also apply to the other variants of the laser bar chip 100.

[0048] Figure 3 shows a schematic sectional side view of a variant of the laser bar chip 100. In the variant shown in Figure 3, the laser bar chip 100 has only the first laser diode 500, 510, the second laser diode 500, 520, the third laser diode 500, 530, the fourth laser diode 500, 540, the fifth laser diode 500, 550, and the sixth laser diode 500, 560. The first laser diode 500, 510, the second laser diode 500, 520, the third laser diode 500, 530, the fourth laser diode 500, 540, and the fifth laser diode 500, 550 are arranged side by side in this order, while the sixth laser diode 500, 560 is arranged on the side of the first laser diode 500, 510 opposite the second laser diode 500, 520. Furthermore, the laser bar chip 100 has a third cathode contact 730 in addition to the first cathode contact 710 and the second cathode contact 720.

[0049] The laser bar chip 100 has an electrically conductive substrate 200. The substrate 200 can be formed, for example, from a semiconductor material with an electrically conductive n-doping. An epitaxial layer 400 is arranged on a top side 201 of the substrate 200. The waveguide structures 600 have been formed in the epitaxial layer 400 by partially removing the epitaxial layer 400. In the region 240 of each waveguide structure 600, the epitaxial layer 400 has an active layer 620. For each laser diode 500, a part of the epitaxial layer 400 facing the substrate 200 forms an n-sided cathode on one side of the active layer 620, and a part of the epitaxial layer 400 facing away from the substrate 200 forms a p-sided anode on the other side of the active layer 620.On the first surface 101 of the laser bar chip 100, the epitaxial layer 400 and the waveguide structures 600 formed therein are covered by an electrically non-conductive passivation 410. In the region of the waveguide structures 600 of the laser diodes 500, the passivation 410 has, at least in sections, anode openings 420, which enable electrical contacting of the laser diodes 500 on the anode side.

[0050] Figure 4 shows a schematic perspective view of the first surface 101 of the variant of the laser bar chip 100 shown in Figure 3. The anode contacts 810, 820, 830, 840 are shown partially transparent in Figure 4 in order to also allow a representation of the waveguide structures 600 of the laser diodes 500 and the anode openings 420 in the passivation 410.

[0051] Figure 4 shows that each of the anode contacts 810, 820, 830, 840 partially covers the waveguide structures 600 of all the laser diodes 500. This is not visible in Figure 3. However, the first anode contact 810 is only electrically connected to the first laser diode 500, 510 and the second laser diode 500, 520. The second anode contact 820 is only electrically connected to the third laser diode 500, 530 and the fourth laser diode 500, 540. The third anode contact 830 is only electrically connected to the fifth laser diode 500, 550. The fourth anode contact 840 is only electrically connected to the sixth laser diode 500, 560.This is achieved in that the passivation 410 has anode openings 420 in the region between the first laser diode 500, 510 and the first anode contact 810 and in the region between the second laser diode 500, 520 and the first anode contact 810, while the passivation 410 electrically insulates the first laser diode 500, 510 and the second laser diode 500, 520 from the second anode contact 820, the third anode contact 830 and the fourth anode contact 840, and the passivation 410 also electrically insulates the first anode contact 810 from the third laser diode 500, 530, the fourth laser diode 500, 540, the fifth laser diode 500, 550 and the sixth laser diode 500, 560 . This applies accordingly to the further laser diodes 500 and the further anode contacts 810 , 820 , 830 , 840 .

[0052] The geometry of the anode contacts 810 , 820 , 830 , 840 can also be selected differently than in Figure 4 .

[0053] The first laser diode 500, 510 and the sixth laser diode 500, 560 are electrically conductively connected to one another on the cathode side via the epitaxial layer 400 and via a first section 210 of the substrate 200. The second laser diode 500, 520 and the third laser diode 500, 530 are correspondingly electrically conductively connected to one another on the cathode side via the epitaxial layer 400 and via a second section 220 of the substrate 200. The fourth laser diode 500, 540 and the fifth laser diode 500, 550 are also electrically conductively connected to one another on the cathode side via the epitaxial layer 400 and via a third section 230 of the substrate 200.

[0054] In the region between the first laser diode 500, 510 and the second laser diode 500, 520, however, the epitaxial layer 400 has an electrically non-conductive interruption 440. Additionally, the first section 210 of the substrate 200 is electrically insulated from the second section 220 of the substrate 200 by an electrically non-conductive region 240. As a result, the first laser diode 500, 510 and the second laser diode 500, 520 are not electrically conductively connected to one another on the cathode side. Accordingly, the epitaxial layer 400 also has an electrically non-conductive interruption 440 between the third laser diode 500, 530 and the fourth laser diode 500, 540, and the second section 220 of the substrate 200 is electrically insulated from the third section 230 by a further non-conductive region 240, so that the third laser diode 500, 530 and the fourth laser diode 500, 540 are also not electrically conductively connected to one another on the cathode side.Furthermore, in this example of the laser bar chip 100, the fifth laser diode 500, 550 and the sixth laser diode 500, 560 are not electrically conductively connected to one another on the cathode side.

[0055] The first cathode contact 710 is electrically conductively connected to the cathode side of the first laser diode 500, 510 via the first section 210 of the substrate 200 and is also electrically conductively connected to the cathode side of the sixth laser diode 500, 560. The second cathode contact 720 is electrically conductively connected to the cathode side of the second laser diode 500, 520 and to the cathode side of the third laser diode 500, 530 via the second section 220 of the substrate 200. The third cathode contact 730 is electrically conductively connected to the cathode side of the fourth laser diode 500, 540 and to the cathode side of the fifth laser diode 500, 550 via the third section 230 of the substrate 200.

[0056] As a result, in the variant of the laser bar chip 100 shown in Figure 3, each of the laser diodes 500 can be individually controlled and supplied with electrical voltage and electrical current. The first laser diode 500, 510 can be controlled via the first anode contact 810 and the first cathode contact 710. The second laser diode 500, 520 can be controlled via the first anode contact 810 and the second cathode contact 720. The third laser diode 500, 530 can be controlled via the second anode contact 820 and the second cathode contact 720. The fourth laser diode 500, 540 can be controlled via the second anode contact 820 and the third cathode contact 730. The fifth laser diode 500, 550 can be controlled via the third anode contact 830 and the third cathode contact 730. The sixth laser diode 500, 560 can be controlled via the fourth anode contact 840 and the first cathode contact 710.

[0057] To produce the variant of the laser bar chip 100 shown in Figure 3, the substrate 200 with the epitaxial layer 400 arranged on the top side 201 is first provided in a known manner. The waveguide structures 600 of the laser diodes 500 are then formed in the epitaxial layer 400 in a known manner. For example, before the anode contacts 810, 820, 830, 840 are produced, the electrically non-conductive interruptions 440 in the epitaxial layer 400 and the non-conductive regions 240 in the substrate 200 can be created. This can be done, for example, using an FIB process (irradiation with a focused ion beam), by means of which the conductivity of the epitaxial layer 400 and the substrate 200 is eliminated in a location-dependent manner by destroying the doping.In this case, the electrically non-conductive interruptions 440 of the epitaxial layer 400 and the non-conductive regions 240 of the substrate 200 can expediently be applied together and simultaneously. Subsequently, the anode contacts 810, 820, 830, 840 and the cathode contacts 710, 720, 730 can be applied and structured. A passivation 790 can optionally be arranged between the individual cathode contacts 710, 720, 730, as shown in Figure 3. Of course, the sequence of the described processing steps can also be selected differently.

[0058] Figure 5 shows a schematic sectional side view of a further variant of the laser bar chip 100. The variant shown in Figure 5 largely corresponds to the variant shown in Figure 3 and can be manufactured according to the method described above. However, in the variant shown in Figure 5, after the cathode contacts 710, 720, 730 have been applied, a rewiring structure 900 is also formed on the second surface 102 of the laser bar chip 100. The rewiring structure 900 comprises one or more layers of electrically non-conductive and electrically conductive materials and makes it possible to redesign the geometry at the cathode contact 710, 720, 730 on the second surface 102 of the laser bar chip 100 without creating unwanted short circuits between the individual cathode contacts 710, 720, 730.The rewiring structure 900 can also be used to specifically electrically connect individual cathode contacts 710, 720, 730 to one another. In a further variant of the laser bar chip 100, a rewiring structure can alternatively or additionally be formed on the first surface 101 of the laser bar chip 100. This rewiring structure can in turn comprise layers of electrically non-conductive and conductive materials. This rewiring structure can be provided to redesign the geometry of the anode contacts 810, 820, 830, 840, 850, 860 accessible on the first surface 101 of the laser bar chip 100 or to electrically connect individual or all of the anode contacts 810, 820, 830, 840, 850, 860 to one another.

[0059] Figure 6 shows a schematic sectional side view of another variant of the laser bar chip 100. In this and all variants of the laser bar chip 100 described below, the first laser diode 500, 510, the second laser diode 500, 520, the third laser diode 500, 530, the fourth laser diode 500, 540, the fifth laser diode 500, 550, and the sixth laser diode 500, 560 are arranged next to one another in this order. This variant of the laser bar chip 100 has, in addition to the first cathode contact 710, the second cathode contact 720, and the third cathode contact 730, a fourth cathode contact 740, a fifth cathode contact 750, and a sixth cathode contact 760. The cathode contacts 710, 720, 730, 740, 750, 760 are in turn arranged on the second surface 102 of the laser bar chip 100.Furthermore, this variant of the laser bar chip 100 has, in addition to the first anode contact 810, the second anode contact 820, the third anode contact 830, and the fourth anode contact 840, a fifth anode contact 850 and a sixth anode contact 860. The anode contacts 810, 820, 830, 840, 850, 860 are in turn arranged on the first surface 101 of the laser bar chip 100.

[0060] In the variant of the laser bar chip shown in Figure 6

[0061] 100, the substrate 200 is electrically non-conductive.

[0062] The substrate 200 can, for example, comprise an undoped semiconductor material. A first via 310, a second via 320, a third via 330, a fourth via 340, a fifth via 350 and a sixth via 360 are formed in the substrate 200. The first cathode contact 710 is electrically conductively connected to the cathode side of the first laser diode 500, 510 via the first via 310. The second cathode contact 720 is electrically conductively connected to the cathode side of the second laser diode 500, 520 via the second via 320. The third cathode contact 730 is electrically conductively connected to the cathode side of the third laser diode 500, 530 via the third via 330. The fourth cathode contact 740 is electrically connected to the cathode side of the fourth laser diode 500, 540 via the fourth via 340.The fifth cathode contact 750 is electrically conductively connected to the cathode side of the fifth laser diode 500, 550 via the fifth through-contact 350. The sixth cathode contact 760 is electrically conductively connected to the cathode side of the sixth laser diode 500, 560 via the sixth through-contact 360. Thus, in the variant of the laser bar chip 100 shown in Figure 6, each laser diode 500 is electrically conductively connected to exactly one of the cathode contacts 710, 720, 730, 740, 750, 760.

[0063] The first anode contact 810 is electrically conductively connected to the anode side of the first laser diode 500, 510 via one of the anode openings 420 in the passivation 410. In contrast, the first anode contact 810 is electrically insulated from the remaining laser diodes 500. The second anode contact 820 is electrically conductively connected to the anode side of the second laser diode 500, 520. The third anode contact 830 is electrically conductively connected to the anode side of the third laser diode 500, 530. Accordingly, the further anode contacts 840, 850, 860 are each connected to exactly one of the laser diodes 500, 540, 550, 560. Thus, each of the laser diodes 500 of the variant of the laser bar chip 100 shown in Figure 6 has both an individual cathode contact 710, 720, 730, 740, 750, 760 and an individual anode contact 810, 820, 830, 840, 850, 860.

[0064] In the variant of the laser bar chip 100 shown in Figure 6, the epitaxial layer 400 has electrically conductive interruptions 440 between the first laser diode 500, 510 and the second laser diode 500, 520, between the second laser diode 500, 520 and the third laser diode 500, 530, between the third laser diode 500, 530 and the fourth laser diode 500, 540, between the fourth laser diode 500, 540 and the fifth laser diode 500, 550, and between the fifth laser diode 500, 550 and the sixth laser diode 500, 560. Thus, the cathode sides of all laser diodes 500 are electrically insulated from one another. In this variant of the laser bar chip 100, the electrically non-conductive interruptions 440 are formed as trenches 450 in the epitaxial layer 400.

[0065] To produce the variant of the laser bar chip 100 shown in Figure 6, the electrically non-conductive substrate 200 with the epitaxial layer 400 arranged on the top side 201 is first provided in a known manner. The laser diodes 500 are then formed in the epitaxial layer 400 in a known manner. The anode contacts 810, 820, 830, 840, 850, 860 can then be formed in a known manner on the first surface 101 of the laser bar chip 100 and electrically conductively connected to the anode sides of the laser diodes 500. Subsequently, the electrically non-conductive interruptions 440 can be created in the epitaxial layer 400, for example by etching the trenches 450. The trenches 450 can then optionally be filled with an electrically non-conductive material. Alternatively, it would also be possible to create the electrically non-conductive interruptions 440 using an FIB method.Before or after this, the vias 310, 320, 330, 340, 350, 360 can be created, for example by first etching openings into the substrate 200 starting from the second surface 102 and then filling these openings with an electrically conductive material, for example gold or copper, for example by a vapor deposition process. Then, the cathode contacts 710, 720, 730, 740, 750, 760 are formed on the second surface 102 of the laser bar chip 100 and electrically conductively connected to the cathode sides of the laser diodes 500.

[0066] Figure 7 shows a schematic sectional side view of a further variant of the laser bar chip 100. The variant shown in Figure 7 largely corresponds to the variant of the laser bar chip 100 shown in Figure 6. However, during production of the variant shown in Figure 7, following the production method described above, a rewiring structure 900 was also formed on the second surface 102 of the laser bar chip 100. The rewiring structure 900 can in turn comprise layers of non-conductive and conductive materials and can serve to redesign the geometry of the cathode contacts 710, 720, 730, 740, 750, 760 accessible on the second surface 102 or to electrically connect individual or all of the cathode contacts 710, 720, 730, 740, 750, 760 to one another.

[0067] In a further variant of the laser bar chip 100, a rewiring structure can alternatively or additionally be formed on the first surface 101 of the laser bar chip 100. This rewiring structure can in turn comprise layers of electrically non-conductive and conductive materials. This rewiring structure can be provided to redesign the geometry of the anode contacts 810, 820, 830, 840, 850, 860 accessible on the first surface 101 of the laser bar chip 100 or to electrically connect individual or all of the anode contacts 810, 820, 830, 840, 850, 860 to one another.

[0068] Figure 8 shows a schematic sectional side view of a further variant of the laser bar chip 100. The variant shown in Figure 8 largely corresponds to the variant in Figure 6. However, the variant of the laser bar chip 100 shown in Figure 8 only has the first anode contact 810. This is electrically conductively connected to the anode sides of all six laser diodes 500, 510, 520, 530, 540, 550, 560. However, the cathode sides of the laser diodes 500 are, as in the variant in Figure 6, each connected to an individual cathode contact 710, 720, 730, 740, 750, 760. This means that in the variant of the laser bar chip 100 shown in Figure 8, each laser diode 500 can be controlled individually.

[0069] The variant of the laser bar chip 100 shown in Figure 8 is manufactured in the same way as the variant shown in Figure 6. However, the electrically non-conductive interruptions 440 in the epitaxial layer 400 are created before the first anode contact 810 is applied, for example, by etching trenches 450. These trenches are subsequently filled with an electrically non-conductive material 455. The first anode contact 810 is then formed on the first surface 101 of the laser bar chip 100.

[0070] In further variants of the laser bar chip 100 not shown in the figures, the latter is designed as in the variants of figures 6 and 8, but has more than one and fewer than six anode contacts 810, 820, 830, 840, 850, 860. In this case, each of the anode contacts 810, 820, 830, 840, 850, 860 can be electrically conductively connected to one or more of the laser diodes 500. In these variants too, the rewiring structures 900 are possible on the first surface 101 and / or on the second surface 102 of the laser bar chip 100. A rewiring structure 900 on the second surface 102 is also possible in the variant shown in figure 8.

[0071] Figure 9 shows a schematic sectional side view of another variant of the laser bar chip 100. The variant shown in Figure 9 has only the first cathode contact 710, the second cathode contact 720, the third cathode contact 730, and the fourth cathode contact 740. Furthermore, this variant has only the first anode contact 810, the second anode contact 820, and the third anode contact 830.

[0072] In this variant, the first anode contact 810 is electrically conductively connected to the anode sides of the first laser diode 500, 510 and the second laser diode 500, 520. The second anode contact 820 is electrically conductively connected to the anode sides of the third laser diode 500, 530 and the fourth laser diode 500, 540. The third anode contact 830 is electrically conductively connected to the anode sides of the fifth laser diode 500, 550 and the sixth laser diode 500, 560.

[0073] The first cathode contact 710 is electrically conductively connected to the cathode side of the first laser diode 500, 510. The second cathode contact 720 is electrically conductively connected to the cathode sides of the second laser diode 500, 520 and the third laser diode 500, 530. The third cathode contact 730 is electrically conductively connected to the cathode sides of the fourth laser diode 500, 540 and the fifth laser diode 500, 550. The fourth cathode contact 740 is electrically conductively connected to the cathode side of the sixth laser diode 500, 560.

[0074] In the variant of the laser bar chip 100 shown in Figure 9, the substrate 200 is again non-conductive, for example as an undoped semiconductor substrate. The epitaxial layer 400 again has an electrically non-conductive interruption 440 between the first laser diode 500, 510 and the second laser diode 500, 520, by means of which interruption the cathode sides of the first laser diode 500, 510 and the second laser diode 500, 520 are electrically insulated from one another. Accordingly, the epitaxial layer 400 also has non-conductive interruptions 440 between the third laser diode 500, 530 and the fourth laser diode 500, 540, as well as between the fifth laser diode 500, 550 and the sixth laser diode 500, 560. The non-conductive interruptions 440 can in turn be formed as trenches 450 which are filled with an electrically non-conductive material 455.It is expedient if the electrically non-conductive interruptions 440 are produced during the production of the variant of the laser bar chip 100 shown in Figure 9 before the anode contacts 810, 820, 830 are applied.

[0075] In the variant of the laser bar chip 100 shown in Figure 9, the anode contacts 810, 820, 830 are again arranged on the first surface 101 of the laser bar chip 100. In addition, in this variant, the cathode contacts 710, 720, 730, 740 are also arranged on the first surface 101 of the laser bar chip 100. For this purpose, the passivation 410 arranged on the epitaxial layer 400 and the waveguide structures 600 has cathode openings 430, which enable an electrically conductive connection between the cathode contacts 710, 720, 730, 740 and the sections of the epitaxial layer 400 connected to the cathode sides of the respective laser diodes 500.

[0076] To produce the variant of the laser bar chip 100 shown in Figure 9, the non-conductive substrate 200 with the epitaxial layer 400 arranged on the top side 201 is first prepared in a known manner. Subsequently, the laser diodes 500 with their waveguide structures 600 are produced in the epitaxial layer 400 in a known manner. Even before the removal of a mask used to produce the waveguide structures 600, this mask can be used to create the trenches 450 and the cathode openings 430. After filling the trenches 450 forming the electrically non-conductive interruptions 440 with the electrically non-conductive material 455, the cathode contacts 710, 720, 730, 740 and the anode contacts 810, 820, 830 can be formed on the first surface 101 of the laser bar chip 100.

[0077] Figure 10 shows a schematic sectional side view of another variant of the laser bar chip 100. The variant shown in Figure 10 largely corresponds to the variant of the laser bar chip 100 shown in Figure 9. However, after the application of the cathode contacts 710, 720, 730, 740 and the anode contacts 810, 820, 830, a rewiring structure 900 was created on the first surface 101 of the laser bar chip 100. The rewiring structure 900 can comprise layers of electrically non-conductive and electrically conductive materials and can serve to modify the geometry of the cathode contacts 710, 720, 730, 740 and the anode contacts 810, 820, 830 accessible on the first surface 101 of the laser bar chip 100. The rewiring structure 900 can also serve to electrically connect individual or all of the cathode contacts 710, 720, 730, 740 or the anode contacts 810, 820, 830 to one another.

[0078] The variants of the laser bar chip 100 shown in Figures 9 and 10, like all other variants of the laser bar chip 100, can be formed with a number of laser diodes 500 different from that shown. The number of cathode contacts 710, 720, 730, 740, 750, 760 and the anode contacts 810, 820, 830, 840, 850, 860 can also be selected differently than shown.

[0079] The invention has been illustrated and described in more detail using preferred embodiments. However, the invention is not limited to the disclosed examples. Other variations may be devised by those skilled in the art.

[0080] LIST OF REFERENCE SYMBOLS Laser bar chip first surface second surface length width substrate top side first section second section third section non-conductive region first via second via third via fourth via fifth via sixth via epitaxial layer passivation anode opening cathode opening electrically non-conductive interruption trench electrically non-conductive material laser diode first laser diode second laser diode third laser diode fourth laser diode fifth laser diode sixth laser diode seventh laser diode 580 eighth laser diode

[0081] 600 waveguide structure

[0082] 610 output facet 620 active layer

[0083] 710 first cathode contact

[0084] 720 second cathode contact

[0085] 730 third cathode contact 740 fourth cathode contact

[0086] 750 fifth cathode contact

[0087] 760 sixth cathode contact

[0088] 790 passivation 810 first anode contact

[0089] 820 second anode contact

[0090] 830 third anode contact

[0091] 840 fourth anode contact

[0092] 850 fifth anode contact 860 sixth anode contact

[0093] 900 rewiring structure

Claims

PATENT CLAIMS 1. Laser bar chip (100), wherein the laser bar chip (100) has at least a first laser diode (500, 510) and a second laser diode (500, 520), wherein the first laser diode (500, 510) and the second laser diode (500, 520) each have a waveguide structure (600), wherein the laser bar chip (100) has a first cathode contact (710) which is electrically conductively connected to the first laser diode (500, 510), and a second cathode contact (720) which is electrically conductively connected to the second laser diode (500, 520), and the laser bar chip (100) has a first anode contact (810) which is electrically conductively connected to the first laser diode (500, 510) and to the second laser diode (500, 520).

2. Laser bar chip (100) according to claim 1, wherein the laser bar chip (100) has a third laser diode (500, 530), wherein the second cathode contact (720) is electrically conductively connected to the third laser diode (500, 530).

3. Laser bar chip (100) according to claim 2, wherein the laser bar chip (100) has a second anode contact (820) which is electrically conductively connected to the third laser diode (500, 530).

4. Laser bar chip (100) according to claim 3, wherein an electrically non-conductive passivation (410) is arranged on the waveguide structure (600) of the first laser diode (500, 510), wherein the passivation (410) is open in the region of the first anode contact (810) so that the first anode contact (810) is electrically conductively connected to the first laser diode (500, 510). is connected, wherein the second anode contact (820) is electrically insulated from the first laser diode (500, 510) by the passivation (410).

5. Laser bar chip (100) according to one of the preceding claims, wherein the first anode contact (810) is arranged on a first surface (101) of the laser bar chip (100), wherein the first cathode contact (710) and the second cathode contact (720) are arranged on a second surface (102) of the laser bar chip (100).

6. Laser bar chip (100) according to claim 5, wherein a rewiring structure (900) is formed on the second surface (102) of the laser bar chip (100).

7. Laser bar chip (100) according to one of the preceding claims, wherein the first anode contact (810), the first cathode contact (710) and the second cathode contact (720) are arranged together on a first surface (101) of the laser bar chip (100).

8. Laser bar chip (100) according to one of claims 5 to 7, wherein a rewiring structure (900) is formed on the first surface (101) of the laser bar chip (100).

9. Laser bar chip (100) according to one of the preceding claims, wherein an epitaxial layer (400) of the laser bar chip (100) has an electrically non-conductive interruption (440) between the first laser diode (500, 510) and the second laser diode (500, 520).

10. Laser bar chip (100) according to claim 9, wherein the epitaxial layer (400) is arranged on an electrically conductive substrate (200), wherein a first portion (210) of the substrate (200) and a second portion (220) of the substrate (200) are electrically insulated from one another by an electrically non-conductive region (240), wherein the first cathode contact (710) is electrically conductively connected to the first laser diode (500, 510) via the first portion (210) of the substrate (200) and the second cathode contact (720) is electrically conductively connected to the second laser diode (500, 520) via the second portion (220) of the substrate (200).

11. Laser bar chip (100) according to claim 9, wherein the epitaxial layer (400) is arranged on an electrically non-conductive substrate (200), wherein the substrate (200) has an electrically conductive first via (310) and an electrically conductive second via (320), wherein the first cathode contact (710) is electrically conductively connected to the first laser diode (500, 510) via the first via (310) and the second cathode contact (720) is electrically conductively connected to the second laser diode (500, 520) via the second via (320).

12. A method for manufacturing a laser bar chip (100) comprising the following steps: - Providing a substrate (200) with an epitaxial layer (400) arranged on a top side (201); - forming at least a first laser diode (500, 510) and a second laser diode (500, 520) in the epitaxial layer (400), wherein the first laser diode (500, 510) and the second laser diode (500, 520) each have a waveguide structure (600); - forming a first cathode contact (710) which is electrically connected to the first laser diode (500, 510), and a second cathode contact (720) which is electrically connected to the second laser diode (500, 520), and - forming a first anode contact (810) which is electrically conductively connected to the first laser diode (500, 510) and to the second laser diode (500, 520).

13. The method according to claim 12, wherein the method comprises the following further step: - Creating an electrically non-conductive interruption (440) in the epitaxial layer (400) between the first laser diode (500, 510) and the second laser diode (500, 520).

14. The method according to claim 13, wherein the substrate (200) is electrically non-conductive, the method comprising the following further step: - creating an electrically conductive first via (310) and an electrically conductive second via (320) in the substrate (200); wherein the first cathode contact (710) is electrically conductively connected to the first laser diode (500, 510) via the first via (310) and the second cathode contact (720) is electrically conductively connected to the second laser diode (500, 520) via the second via (320).

15. The method according to claim 13, wherein the substrate (200) is electrically conductive, the method comprising the following further step: - applying an electrically non-conductive region (240) in the substrate (200) in order to electrically isolate a first portion (210) of the substrate (200) and a second portion (220) of the substrate (200) from one another; wherein the first cathode contact (710) is electrically conductively connected to the first laser diode (500, 510) via the first portion (210) of the substrate (200) and the second cathode contact (720) is electrically conductively connected to the second laser diode (500, 520) via the second portion (220) of the substrate (200).

16. The method according to claim 15, wherein the electrically non-conductive interruption (440) in the epitaxial layer (400) and the electrically non-conductive region (240) in the substrate (200) are produced jointly by an FIB process.

17. The method according to claim 13 or 15, wherein the electrically non-conductive interruption (440) is produced by etching a trench (450) in the epitaxial layer (400).

18. The method according to claim 17, wherein the trench (450) is filled with an electrically non-conductive material (455).

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