DE102010047451A1 - Edge-emitting semiconductor laser - Google Patents

Abstract

An edge emitting semiconductor laser is disclosed, with
- A semiconductor body (1) comprising at least two in the transverse direction (101) juxtaposed strip emitter (10), each strip emitter (10) comprises at least one set up for generating electromagnetic radiation active zone (2);
- At least two facets (11) on the active zones (2), which form at least one resonator (33) for at least one of the strip emitter (10);
- At least two in the transverse direction (101) spaced from each other contact surfaces (3) which are mounted on an outer surface (12) of the semiconductor body (1), wherein
- each stripe emitter (10) is assigned a contact surface (3),
- Over the contact surfaces (3) during operation of the semiconductor laser (100) current in at least one of the strip emitter (10) is impressed, and
- At least two of the strip emitter (10) are electrically operated separately.

Description

An edge-emitting semiconductor laser and a laser device with such an edge-emitting semiconductor laser are specified.

An object to be solved is to provide an edge emitting semiconductor laser whose optical output power is adjustable.

According to at least one embodiment of the edge emitting semiconductor laser, the latter has a semiconductor body which comprises at least two strip emitters arranged side by side in the transverse direction. By way of example, the semiconductor body is formed with a substrate, on which a semiconductor layer sequence is epitaxially grown. For example, the substrate forms the strip emitters at least in places, together with the semiconductor layer sequence. The strip emitters are preferably monolithically integrated, that is to say connected by epitaxially deposited material. "Transverse direction" in this context means a direction which runs parallel to the epitaxially grown semiconductor layer sequence and perpendicular to a main emission direction of the edge emitting semiconductor laser. The two strip emitters can then directly adjoin one another in the transverse direction and merge into one another. This may mean that in the transverse direction between respectively adjacent strip emitters, for example, no electrically insulating material is arranged and / or attached between the strip emitters.

Each of the strip emitters comprises at least one active zone set up to generate electromagnetic radiation. The active zone may be a layer that emits radiation in the range of ultraviolet to infrared light. The active zone preferably comprises a pn junction, a double heterostructure, a single quantum well (SQW) or a multiple quantum well (MQW) structure for generating radiation. The term quantum well structure unfolds no significance with regard to the dimensionality of the quantization. It thus includes quantum wells, quantum wires and quantum dots and any combination of these structures.

The stripe emitters can also comprise a plurality of active zones, which are arranged one above the other in the vertical direction. In this context, "vertical direction" means a direction perpendicular to the epitaxially grown semiconductor layer sequence.

In accordance with at least one embodiment, the active zones of the strip emitters transversely merge into each other directly and form at least one transversely continuous and contiguous active zone of the edge emitting semiconductor laser.

In accordance with at least one embodiment, the individual active zones of the strip emitters are separated in the transverse direction by semiconductor material arranged between the active zones, which is, for example, radiation-inactive.

According to at least one embodiment of the edge-emitting semiconductor laser, the latter has at least two facets on the active zones, which form at least one resonator for at least one of the strip emitters. The at least two facets are formed by mutually opposite side surfaces of the semiconductor body, which are at least partially reflective for electromagnetic radiation generated in the active zone. The two facets form at least one optical resonator for at least one of the strip emitters. For example, the two facets form a resonator for each of the stripe emitters. In this case, each strip emitter may be assigned a resonator unambiguously, for example one-to-one. For example, the number of stripe emitters is equal to the number of resonators for the stripe emitters. The main emission direction of the semiconductor laser preferably runs parallel to a resonator axis of the resonator formed by the facets.

According to at least one embodiment of the edge-emitting semiconductor laser, the latter comprises at least two transversely spaced contact surfaces which are mounted on an outer surface of the semiconductor body. This means that the contact surfaces are arranged on the same side of the semiconductor body. For example, a region of the outer surface of the semiconductor body in the transverse direction between adjacent contact surfaces is free of the material of the contact surfaces. In other words, the contact surfaces are spaced transversely by at least one intermediate region. In a plan view of the edge-emitting semiconductor laser, the intermediate region is then delimited by two contact surfaces which adjoin each other in the transverse direction and, for example, the outer surface of the semiconductor body. In other words, the contact surfaces in the transverse direction are each separated by an intermediate region.

In accordance with at least one embodiment of the edge-emitting semiconductor laser, each stripe emitter is assigned a contact surface uniquely. For example, each stripe emitter is uniquely associated with a contact area.

According to at least one embodiment, current is injected into at least one of the strip emitters via the contact surfaces during the operation of the semiconductor laser. In other words, the active zones of the strip emitter are contacted and energized by means of the contact surfaces. For example, the contact surfaces serve for p-side contacting of the strip emitter and thus of the edge-emitting semiconductor laser. To impress the current through the contact surfaces in the strip emitter, the contact surfaces may be in direct contact with the outer surface of the semiconductor body. For example, the intermediate areas are not formed electrically conductive or contactable. Preferably, no current is impressed in the strip emitter on the intermediate areas.

In accordance with at least one embodiment, at least two of the strip emitters can be operated separately from one another. "Electrically operable" means that, for example, current of a predefinable height can be impressed independently of one another via the respective contact surfaces in the at least two strip emitters. Furthermore, "electrically operable" means that the at least two strip emitters can be set and / or controlled in a predetermined manner with respect to their operating voltage, operating temperature and / or operating time.

In accordance with at least one embodiment of the edge-emitting semiconductor laser, the semiconductor laser has a semiconductor body which comprises at least two laterally juxtaposed stripe emitters, each stripe emitter comprising at least one active zone set up to generate electromagnetic radiation. Furthermore, the edge-emitting semiconductor laser has at least two facets on the active zones, which forms at least one resonator for at least one of the strip emitters. At least two spaced-apart in the transverse direction of contact surfaces are mounted on an outer surface of the semiconductor body, each strip emitter is assigned a contact surface unique. During operation of the semiconductor laser, current is impressed into at least one of the strip emitters via the contact surfaces, wherein at least two of the strip emitters can be operated separately from one another.

The edge-emitting semiconductor laser described here is based, inter alia, on the knowledge that an optical output power of an edge-emitting semiconductor laser with a single active zone can be set individually via its contact surface, for example only via the current level. In other words, the optical output power of the edge emitting semiconductor laser is determined by the single electrical contact area and the optical characteristics of the single active area. For example, the active zone can only be regulated in an absolute current or voltage level, for example. In other words, with respect to the emission of electromagnetic radiation, no selection can be made between different active zones and their associated pads.

In order to be able to individually set and adapt the optical output power and the add-on of the edge-emitting semiconductor laser, the semiconductor laser described here makes use, inter alia, of the idea to provide a semiconductor body comprising at least two laterally juxtaposed strip emitters which can be operated separately from one another. In other words, the optical output power can be adjusted to the individual needs of the user via a selection of the electrically operated active zones. Such an edge-emitting semiconductor laser is therefore particularly variable in its field of application, for example in projection applications. Furthermore, such an edge-emitting semiconductor laser is particularly compact and space-saving.

According to at least one embodiment, at least one strip emitter is electrically uncontacted. For example, the uncontacted strip emitter is then also electrically inoperable. For example, for this purpose, the contact surface assigned to the strip emitter is not electrically connected. The uncontacted strip emitter may be a strip emitter which is not required for use of the semiconductor laser and / or which does not meet the specifications set for it. In other words, such a strip emitter may be unsuitable for the particular application of the semiconductor laser. It is thus advantageously avoided that the inappropriate strip emitter negatively influences the semiconductor laser, for example with regard to the optical output power.

According to at least one embodiment of the edge-emitting semiconductor laser, the latter comprises at least two connection surfaces, which are mounted on the outer surface of the semiconductor body, wherein each contact surface is uniquely associated with a contact surface and electrically conductively connected to this contact surface. The pads are used for electrical contacting of the contact surfaces. Preferably, current of a predeterminable height is impressed via the connection surfaces and the respective contact surfaces associated therewith for external electrical contacting of the connection surfaces in the respective strip emitters. In particular, the contact surfaces do not serve for external electrical contacting. Since the connection surfaces are electrically conductively connected to the contact surfaces assigned to them, the connection surfaces, just like contact surfaces, form, for example, a p-type contact surface. side contact of the semiconductor laser. Preferably, the contact surfaces are not electrically contacted from the outside. In other words, only the pads serve for external electrical contacting of the edge-emitting semiconductor laser.

According to at least one embodiment of the edge-emitting semiconductor laser, each pad is directly connected to the contact surface assigned to it. Preferably, the pad and the contact surface are integrally formed and form a unit. In this context, "direct" means that an electrically conductive connection is established between the connection area and the contact area without, for example, a conductor track arranged between the connection area and the contact area. For example, for this purpose, the pad and the contact surface are applied to the outer surface of the semiconductor body in a single method step. For example, the pad and the contact surface are formed with the same material.

In accordance with at least one embodiment, at least one connection surface is arranged on the outer surface of the semiconductor body in the transverse direction between respectively adjacent contact surfaces. When viewing the contact surfaces in pairs, the connection surfaces on the outer surface are guided, for example, starting from the contact surface assigned to them in the direction of the respectively adjacent contact surface.

According to at least one embodiment of the edge-emitting semiconductor laser, the outer surface has at least one region between transversely adjacent contact surfaces, which is free of the connection surfaces.

In accordance with at least one embodiment of the edge-emitting semiconductor laser, at least one connection surface and a contact surface not assigned to it have at least one overlap region in which the connection surface and the contact surface overlap in the vertical direction at least in places. In the vertical direction, at least in places, an electrical insulation is arranged between the connection surface and the contact surface in the overlapping region. The connection surface can be guided away in the vertical direction via a contact surface which is not assigned to it. The locations of the pad and pad, where both overlap in the vertical direction, each form the overlap area. In a plan view of the edge-emitting semiconductor laser, the connection surface is in the overlap region above the contact surface. The contact surface may be concealed in places in a plan view of the outer surface of the semiconductor laser through the pad. For example, the electrical insulation is formed by at least one electrically insulating layer.

According to at least one embodiment of the edge-emitting semiconductor laser, each pad is electrically conductively connected via at least one contact web to the contact surface assigned to it. For example, a contact surface and a pad associated therewith are associated with a contact land. In other words, the connection surface, the contact web and the contact surface can form a contacting group for contacting the strip emitter, which in each case is uniquely assigned to it.

In accordance with at least one embodiment of the edge-emitting semiconductor laser, at least two connection surfaces are arranged on the same side of a contact surface on the outer surface of the semiconductor body. For example, all connection pads are arranged on one side of a contact surface. In this case, no pads are arranged in the transverse direction between the contact surfaces.

In accordance with at least one embodiment of the edge emitting semiconductor laser, at least one contact web and at least one contact surface not assigned to the contact web have at least one further overlap region in which the contact web and the contact surface overlap in the vertical direction at least in places. In the vertical direction, at least in places, further electrical insulation is arranged between the contact web and the contact surface in the further overlap region. For example, the further electrical insulation and the electrical insulation are formed with the same material.

According to at least one embodiment of the edge-emitting semiconductor laser, at least one contact web has an interruption, by means of which the electrically conductive connection between a contact surface and the contact surface assigned to it can be predetermined. The interruption of the contact bridge can be permanent. This may mean that the interruption can not be repaired without repair measures. For example, the contact bar is permanently interrupted in its course. This may mean that the contact web is cut through or cut through mechanically and / or by means of high-energy laser light, for example by material removal, and is thus interrupted.

In accordance with at least one embodiment of the edge-emitting semiconductor laser, at least two of the strip emitters have resonator lengths of different lengths. For example, one of the facets is divided into individual partial facets, wherein each partial facet is uniquely associated with a strip emitter. In other words, the facet is no longer a level. The respective resonator length of a strip emitter is a distance in a direction parallel to the main emission direction of the strip emitter between respectively adjacent part facets. By way of example, the partial facets are introduced into the semiconductor body by means of a dry and / or wet-chemical etching process. In addition, the lengths of the contact surfaces, that is, the extension of the contact surfaces in the main emission direction of a strip emitter may be of different lengths. In other words, the length of the contact surfaces may correspond to the different resonator lengths of the individual strip emitters.

In accordance with at least one embodiment, the semiconductor body is based on a III-nitride semiconductor material. "III-nitride semiconductor material" in the present context means that the semiconductor body comprises or consists of a nitride semiconductor material, preferably Al _n Ga _m In _1-nm N, where 0 ≦ m ≦ 1, 0 ≦ n ≦ 1 and m + n ≤ 1.

According to at least one embodiment, rib depths of laterally juxtaposed strip emitters differ by at least 10 nm. For example, laterally juxtaposed stripe emitters directly adjoin one another. For example, the strip emitters are fin emitters which have at least one rib. The extension of the rib in the vertical direction is then the respective rib depth. It has been recognized that, starting from such a difference in the rib depths, the edge-emitting semiconductor laser can be used particularly flexibly, since the optical output powers of respectively adjacent strip emitters can be distinguished and demarcated from one another in a particularly simple manner due to the different rib depths. In this respect, for example, only the used for the particular application of the edge emitting semiconductor laser and / or desired strip emitter are electrically operated.

In accordance with at least one embodiment, rib widths of laterally juxtaposed strip emitters differ by at least 100 nm. The extent of a rib in the transverse direction is then the respective rib width. Since the respective rib width of a strip emitter likewise has an influence on the optical output power, the strip stripters correspondingly required can be operated by means of such differences in the rib widths only for the respective application.

In other words, the rib width and the rib depth are manipulated variables, for example with regard to the optical output power of a strip emitter. Depending on the rib width and the rib depth, the edge-emitting semiconductor laser comprises strip emitters of different optical output power, the strip emitters being able to be operated separately from one another.

In addition, a laser device is specified.

In accordance with at least one embodiment, the laser device comprises at least one edge-emitting semiconductor laser according to at least one of the embodiments described here. That is, the features listed for the edge emitting semiconductor laser described herein are also disclosed for the laser device described herein, and vice versa.

In accordance with at least one embodiment, at least two strip emitters are electrically contacted via the respective contact surface assigned to them.

According to at least one embodiment of the laser device, the drive device comprises a drive device for operating the strip emitters, wherein the drive device is set up to drive at least two of the strip emitters in response to at least one of the conditions of maximum operating time, predeterminable minimum intensity of the electromagnetic radiation emitted by each of the at least two strip emitters. For example, the maximum operating time of the strip emitter is a time period predetermined, for example, by a user of the laser device, beyond which the strip emitter is no longer able to fulfill predefinable criteria. In stripe emitters not driven by the drive device, no current is impressed via the contact surfaces assigned to them. These strip emitters are then not operated electrically.

In accordance with at least one embodiment of the laser device, the drive device is set up to deactivate the strip emitter after reaching at least one of the conditions for a strip emitter operated by the drive device. This may mean that an electrically conductive connection between an external energy source and the strip emitter is interrupted by the drive device. In deactivated strip emitters, no current is impressed on the contact surfaces assigned to them during operation of the laser device. During operation of the laser device, already consumed strip emitters could reduce the optical output power and / or lead to short circuits in the semiconductor laser and / or to far field errors of the semiconductor laser. "Used strip emitter" means in this context, such that after a certain period of operation such fringe emitters no longer fulfill the frame specifications applied to them, such as the intensity of the emitted light. Disabling the spent frit emitter will prevent these negative effects, although the fringe emitter may remain connected throughout its life.

In accordance with at least one embodiment, the number of strip emitters in operation is constant during operation of the laser device. If a certain number of simultaneously operated and / or preselected strip emitters, for example each having the same optical output power, are required for an application of the laser device, an already consumed strip emitter can be replaced by a strip emitter which has not yet been operated. Advantageously, an intensity emitted by the semiconductor laser can thus be kept constant over the entire operating period of the laser device. As a result, the operating criteria applied to the semiconductor laser can be kept constant over as long a period as possible, as a result of which the service life of the laser device is significantly increased.

In the following, the edge-emitting semiconductor laser described here as well as the laser device described here will be explained in greater detail on the basis of exemplary embodiments and the associated figures.

The 1A to 8th show in schematic views exemplary embodiments of an edge-emitting semiconductor laser described here.

The 9 shows a schematic view of an embodiment of a laser device described herein.

In the exemplary embodiments and the figures, the same or equivalent components are each provided with the same reference numerals. The illustrated elements are not to be considered as true to scale, but individual elements may be exaggerated to better understand.

In the 1A is a schematic plan view of an edge-emitting semiconductor laser described here 100 with a semiconductor body 1 represented, for example, based on a III-nitride semiconductor material. The semiconductor body 1 includes two in a transverse direction 101 juxtaposed strip emitters 10 , which each have an active zone 2 for generating electromagnetic radiation. On an outer surface 12 of the semiconductor body 1 are two contact surfaces 3 arranged. Here are the two contact surfaces 3 in the transverse direction 101 spaced apart. That is, in the transverse direction 101 between adjacent contact surfaces 3 an intermediate region is formed which is free from the contact surfaces 3 is. It is each strip emitter 10 a contact surface 3 uniquely assigned. About the contact surfaces 3 is during operation of the semiconductor laser 100 Electricity into the strip emitter 10 imprinted. These are the strip emitters 10 electrically operated separately from each other. For example, the contact surfaces form 3 a p-side contact of the edge emitting semiconductor laser 100 ,

Under electrical contact, the active zones emit 2 electromagnetic radiation in the range of ultraviolet to infrared light. It is conceivable that under electrical contacting of the two active zones 2 the two strip emitters 10 the active zones 2 emit electromagnetic radiation in a same wavelength range, completely separate wavelength ranges or partially overlapping wavelength ranges.

Furthermore, the edge emitting semiconductor laser 100 at least two facets 11 at the active zones 2 on. Here are the two facets 11 one resonator each 33 for a strip emitter 10 , That is, in the operation of the edge-emitting semiconductor laser 100 is every stripe emitter 10 a resonator 33 uniquely assigned. It is about one of the facets 11 electromagnetic radiation from the edge-emitting semiconductor laser 100 decoupled.

Furthermore, the edge emitting semiconductor laser 100 two connection surfaces 4 on which on the outside surface 12 of the semiconductor body 1 in the transverse direction 101 between the contact surfaces 3 are arranged. Each of the connection surfaces 4 is a contact surface 3 clearly assigned and connected to this electrically conductive. The connection surfaces serve here 4 for electrical contacting of the contact surfaces 3 , From the 1A it can be seen that each connection surface 4 with the contact surface assigned to it 3 directly connected. That is, every pad 4 forms with its associated contact surface 3 a unit and is formed with this coherent. Here are the two connection surfaces 4 on the outside surface 12 of the semiconductor body 1 in the transverse direction 101 between the two contact surfaces 3 arranged. The contact surfaces 3 are in the transverse direction 101 At least 20 microns apart. Such a distance range ensures that the connection surfaces 4 in the transverse direction 101 between the contact surfaces 3 on the outside surface 12 can be arranged. In other words, in such a distance range, the contact surfaces 3 the connection surfaces 4 between the contact surfaces 3 ,

For example, one of the strip emitters 10 as a test laser compared to the other strip emitter 10 serve. For this purpose, the test laser in the context of stress tests up to his and / or beyond his load limits, for example, in terms of his Bestromungshöhe and / or life, operated while the other strip emitter 10 is operated within its load limits. During and / or after such stress tests (also robustness or aging-overstress test), the two strip emitters 10 then, for example, compared with each other in terms of their physical behavior.

In the 1B is in the schematic plan view of another embodiment of an edge-emitting semiconductor laser described here 100 shown. Unlike the one in the 1A illustrated semiconductor laser 100 is an area between the ones in the transverse direction 101 adjacent contact surfaces 3 free of connection surfaces 4 , In other words, the pads are 4 in each case starting from the contact surface assigned to it 3 in the direction away from the respectively adjacent contact surface 3 guided. The connection surfaces 4 are therefore on the outside surface 12 of the semiconductor body 1 in each case in edge regions of the two strip emitters 10 arranged. The contact surfaces 3 are in the transverse direction 101 At most 10 microns apart. Such a distance range ensures that the edge areas on the outer surface 12 are big enough to the connecting surfaces 4 to arrange on it. In other words, in such a distance range fit the pads 4 in the transverse direction 101 no longer between the contact surfaces 3 ,

In the 1C is a schematic plan view of another embodiment of an edge emitting semiconductor laser described here 100 shown. In contrast to the previous embodiments have a connection surface 4 and a non-associated contact surface 3 an overlap area 24 on. The connection surface overlaps 4 and the contact area 2 in the vertical direction V in the overlapping area 24 , In the vertical direction V between the connection surface 4 and the contact surface 3 is an electrical insulation 41 , in the present case a dielectric layer, which is arranged in the overlap region 24 the connection surface 4 from the contact surface 2 electrically isolated.

In the 2A is another embodiment of an edge emitting semiconductor laser described herein 100 shown in a schematic plan view. The edge-emitting semiconductor laser 100 has three contact surfaces 3 as well as each of the contact surfaces 3 clearly assigned connection surfaces 4 on. Here are the three pads 4 in the plan view on one side, in this view on the left, from the contact surfaces 3 arranged. That is, on the outside surface 12 of the semiconductor body 1 in the transverse direction 101 between the contact surfaces 3 no connection surfaces 4 are arranged. In other words, the contact surfaces 3 and the connection surfaces 4 separated from each other and grouped on the outer surface 12 arranged. Furthermore, each connects a contact bridge 5 a connection surface 4 with one of the connection surface 4 clearly assigned contact surface 3 , In other words, each is a contact surface 3 and a mating surface associated therewith 4 a contact bridge 5 assigned. The contact bridges 5 and their unassigned contact surfaces 3 have three more overlap areas 25 on where the contact bridges 5 each the contact surfaces 3 overlap and obscure in a plan view. In the vertical direction V between the contact webs 5 and the respective contact surfaces 3 is in the three other overlap areas 25 another electrical insulation 42 arranged. In this case, the further electrical insulation 42 and the electrical insulation 41 be formed with the same material.

The 2 B shows a schematic side view of the edge emitting semiconductor laser 100 according to the 2A , Here are the three stripe emitters 10 each in the form of rib emitters 10A . 10B and 10C educated. Each fin emitter has a rib depth RT and a rib width RB. From the 2 B It can be seen that each of the rib emitters 10A to 10C the same rib width RB, but each having different rib depths RT. By means of the different rib depths RT can strip emitter 10 each with different optical output powers, for example, monolithically integrated on a substrate. For example, the ribs of the rib emitter 10A to 10C over the outer surface 12 of the semiconductor body 1 in the semiconductor body 1 etched. In the present case, the rib emitter 10A the smallest and the rib emitter 10C the largest rib depth RT, wherein the respective rib depths RT differ from directly adjacent rib emitters by at least 10 nm. Consequently, when electrical current is impressed, it is found across the contact surface 2 in the rib emitter 10A within the rib emitter 10A the largest current expansion takes place. This shows the rib emitter 10A the largest emission area at the active zone 2 on, whereby the optical output power and a steepness of the rib emitter 10A the highest of the three rib emitters 10A until 10C is. However, the rib emitter has 10A the highest threshold current, from which the rib emitter 10A begins to emit electromagnetic radiation. Although the optical Output power and slope of the rib emitter 10C the least, the rib emitter 100 however, has the lowest power consumption and the lowest threshold current. In addition, different lateral far-field angles of the active zones 2 emitted electromagnetic radiation can be set individually over the rib depths RT. For example, the respective ones for the use of the edge-emitting semiconductor laser 100 suitable strip emitter 10 selectively electrically contacted and connected from the outside. That is, as needed, between the rib emitters 10A to 10C can be selected.

In the 2C is a schematic side view of another embodiment of an edge-emitting semiconductor laser described here 100 shown. Unlike the ones in the 1A to 2 B described edge emitting semiconductor lasers 100 have the in the 2C described rib emitter 10A to 10C different rib widths RB, wherein the rib depths RT are the same. The rib emitter 10A , with its smallest rib width RB, has the lowest threshold current under electrical contacting and, because of its smallest rib width RB, the smallest emission surface. In this case, the respective rib widths RB of two directly adjoining rib emitters differ by at least 100 nm. However, the small emission area of the rib emitter leads 10A to a local heating in the area of the interface semiconductor material / air, in particular in the region of the active zone 2 , This local heating due to absorption or re-absorption of the electromagnetic radiation by the semiconductor material of the fin emitter 10A can lead to the melting of the affected semiconductor regions and thereby the semiconductor laser 100 to destroy. In general, one then speaks of Catastrophical Optical Damage (also COD). One such catastrophic optical damage is in the rib emitter 10A most likely from the three rib emitters 10A to 10C , In contrast, the rib emitter 10C however, with its largest rib width RB and concomitant largest emission area designed for the highest optical output, it has the highest threshold current. During operation of the rib emitter 10C is a catastrophic optical damage on the rib emitter 10C least likely.

Because the strip emitter 10 and their optical output as well as 2A executed, can be adjusted and defined by the respective rib widths RB, the optical and / or physical properties of the strip emitter 10 , so the rib emitter 10A to 10C be set individually and independently of each other via an adaptation of the respective rib width RB and / or rib depth RT.

The 3A shows a further embodiment of an edge-emitting semiconductor laser described here 100 in a schematic side view, in which the semiconductor body 1 with two stiffener emitters 10 is formed, wherein it is a strip emitter 10 around a rib emitter 10R and the other strip emitter 10 around an index-guided wide-band emitter 10Bi is. The rib emitter 10R is together with the broadband emitter 10Bi integrated monolithically. Preferably, the rib emitter emits 10R monomode and the broadband emitter 10Bi multimode electromagnetic radiation. Due to the monolithic integration of both strip emitters 10 is thus a semiconductor laser 100 feasible, which is particularly compact and space-saving. Such a semiconductor laser 100 may be particularly suitable for projection applications, since the rib emitter 10R for projection of small image diagonals (also flying spot applications) and the broadband emitter 10Bi is suitable for larger image diagonals. In other words, depending on the need and projection requirements of the rib emitter 10R and / or the breadth strip emitter 10Bi come into use.

In the 3B is another embodiment of an edge emitting semiconductor laser described herein 100 shown in a schematic side view, in which, in contrast to the 3A instead of the index-guided broadband emitter 10Bi a profit-driven broadband emitter 10BIG Use finds. For example, the profit-guided wide-band emitter 10BIG a gain-guided oxide strip emitter or a strip strip rib emitter. Next is in the 3B shown on the outside surface 12 in the area of the broadband emitter 10BIG next to the contact surface 2 an electrically insulating, dielectric layer 43 arranged.

The insulating, dielectric layer 43 is used for electrical insulation of the part of the outer surface 12 in the area of the broadband emitter 10BIG , over which no electrical current is to be impressed in these. In other words, the insulating dielectric layer opens and / or defines 43 a current stop over the broadband emitter 10BIG , By means of which only at the designated places electrical current through the contact surface 3 over the outer surface 12 in the broadband emitter 10BIG is impressed.

The 3C and 3D show the operation of the in the 3A or 3B described edge emitting semiconductor laser 100 , Shown is a single-mode emission of the edge-emitting semiconductor laser 100 , This is just the ribs emitter 10R energized. Such operation of the semiconductor laser 100 can be used in particular in projection applications in the flying spot technology. Conversely, in the 3D shown that here only the broadband emitter 10Bi or 10BIG is energized and the semiconductor laser 100 only multimode electromagnetic radiation of the broadband emitter 10Bi emitted. Such an operation can be used in particular for projection applications in image-based technologies.

In the 4 is a schematic plan view of another embodiment of an edge emitting semiconductor laser described here 100 described. On the outside surface 12 are a total of seven contact surfaces 3 in the transverse direction 101 spaced apart from each other. Next is each of the contact surfaces 3 a connection surface 4 uniquely assigned, with all pads 4 on one side of a contact surface 3 are arranged. In other words, the areas of the outer surface 12 in the transverse direction 101 between the contact surfaces 3 free from the connection surfaces 4 , The contact surfaces 3 and the connection surfaces 4 are each separated and arranged in groups. The contact bridges 5 each connect a connection surface 4 with a contact surface assigned to it 3 electrically, wherein one of the contact webs 5 is severed. Through the separation is an electrically conductive connection between the respective contact surface 3 and its associated pad 4 interrupted. A preselection of the strip emitter 10 which can be electrically contacted and energized externally can therefore be hit by the interruption. For example, can be specified as strip emitter 10 , which do not meet the requirements imposed on them, for example, in terms of their optical output power, separated accordingly and thus be selected out. In the separated strip emitter 10 can via its associated contact surfaces 2 no electricity to be impressed. For example, inhomogeneously radiation-emitting stripe emitters 10 from the homogeneous radiation-emitting strip emitters 10 separated. This means that only in homogeneous radiation-emitting stripe emitter 10 Electricity over the contact surfaces 3 can be embossed. For example, this is done by severing the contact bridge 5 by means of a high-energy laser light. For example, "homogeneous" means that such a strip emitter 10 has an emission image in the far field, which is ideally formed in the form of a Gaussian curve. Accordingly, "inhomogeneous" can mean that such an emission image deviates at least in places from such a Gaussian curve. In particular, a homogeneous emission image can be better matched to a Gaussian curve than an inhomogeneous emission image.

In the 5 is an edge-emitting semiconductor laser in a schematic plan view 100 shown with only two pads 4 electrically contacted. In the 5 this is schematically represented by two contacting symbols 45 clarified. About non-contacted pads 4 may during operation of the edge emitting semiconductor laser 100 no electricity in the strip emitter 10 be embossed. In other words, the selection of suitable strip emitters happens here 10 through targeted contacting of the connection surfaces 4 (also pinning). Further, the optical output power of the semiconductor laser 100 and / or those of the active zones 2 emitted wavelength ranges corresponding to the number of contacted pads 4 set individually, for example, be increased.

The 6A shows in a schematic perspective view of the edge emitting semiconductor laser 100 according to one of the preceding embodiments, wherein additionally one of the outer surface 12 of the semiconductor body 1 in the vertical direction V opposite outer surface 13 has a structuring. There are areas 13A the outer surface 13 in the vertical direction V below the contact surfaces 3 fan-shaped.

From the 6B is a schematic, perspective view of another embodiment of the edge-emitting semiconductor laser described here 100 in which the areas 13A alternatively or in addition to the structuring also have bevels.

For example, by means of the targeted in the semiconductor body 1 introduced structuring of the outer surface 13 of the semiconductor body 1 a predetermined heat dissipation and a setting of the active zones 2 emitted wavelengths are made possible. This may be due to, for example, structuring caused gradients in indium concentration within the active zones 2 be reached.

The 7 shows a schematic plan view of another embodiment of a semiconductor laser described here 100 , In contrast to the edge-emitting semiconductor lasers shown in the preceding figures 100 is on at least one of the facets 11 at least one passivation layer 15 applied. That is, the passivation layer 15 in direct contact with the facet 11 stands. The at least one passivation layer 15 At least one of the materials contains silicon dioxide, silicon nitride, titanium dioxide, aluminum dioxide or silicon. For example, the passivation layer exists 15 completely made of one of the mentioned materials. Furthermore, it is possible that on a facet 11 of the semiconductor body 1 alternately different layers of said materials are applied. Preferably, all exposed areas of the active zones 2 applied one or more of said passivation layers. Likewise, it is conceivable that a passivation layer also applies to further exposed points of the semiconductor body 1 is applied. In the transverse direction 101 along the facet 11 has the passivation layer 15 a gradient in their thickness. This will in the transverse direction 101 along the facet 11 a mirroring gradient on the facet 11 specifiable set. In other words, depending on the changing thickness of the passivation layer 15 the decoupling properties of the facet 11 different and individually adjustable.

The 8th shows a schematic plan view of another embodiment of an edge emitting semiconductor laser described here 100 where the strip emitter 10 each resonator lengths of different lengths 34 exhibit. Furthermore, the semiconductor laser 100 with the different resonator lengths 34 corresponding respectively different length contact surfaces 3 on. For example, the respective resonator length 34 by means of individually in the semiconductor body 1 (dry) etched partial facets 111 be reached, wherein the partial facets 111 then together the facet 11 of the semiconductor laser 100 can train.

The 9 shows a schematic plan view of a laser device described here 200 , In the semiconductor laser 100 it is the embodiment according to the 5 In contrast, each of the pads 4 electrically contacted. A drive device 300 can via a control line 301 each of the strip emitters 10 depending on at least one of the conditions maximum operating time, predetermined minimum intensity of the each of the stripe emitter 10 trigger emitted electromagnetic radiation. This is in the 9 the edge-emitting semiconductor laser 1 00 executed in the form of a "magazine laser". During operation of the laser device 200 always only one connection surface 4 electrically energized. In other words, only a single stripe emitter 10 by the drive device 300 controlled and electrically operated.

After a predetermined period of time, for example, the life of the strip emitter 10 , will be another strip emitter 10 from the drive device 300 controlled and electrically operated. The spent strip emitter 10 , which has already exceeded its life is, by the driving device 300 disabled and turned off, but it can remain connected. Deactivation can prevent it from occurring in the laser device 200 to short circuits or a reduction in the optical output power of the edge-emitting semiconductor laser 100 comes. The number of strip emitters in operation 10 is constant and limited to one in the present embodiment. Until reaching the overall lifetime of the laser device 200 can any strip emitter 10 be operated consecutively and thus temporally successive. In addition, it is conceivable that the drive device 300 the strip emitters 10 depending on its ambient temperature and / or its power consumption. The wavelength of the laser device 300 emitted electromagnetic radiation can be matched to the ambient temperature. The laser device described here 300 can be used in particular for spectroscopic applications, as a setting of the wavelength of the semiconductor laser 100 emitted electromagnetic radiation, for example via the drive device 300 , is possible over a broad spectrum of electromagnetic radiation.

The invention is not limited by the description with reference to the embodiments. Rather, the invention covers every new feature and every combination of features, which in particular includes any combination of features in the patent claims, even if this feature or this combination itself is not explicitly stated in the patent claims or the exemplary embodiments.

Claims (15)

Edge-emitting semiconductor laser ( 100 ), comprising: - a semiconductor body ( 1 ), at least two in the transverse direction ( 101 ) juxtaposed strip emitters ( 10 ), each strip emitter ( 10 ) at least one active zone set up to generate electromagnetic radiation ( 2 ); - at least two facets ( 11 ) at the active zones ( 2 ), the at least one resonator ( 33 ) for at least one of the stripe emitters ( 10 ) form; At least two in the transverse direction ( 101 ) spaced contact surfaces ( 3 ), which are located on an outer surface ( 12 ) of the semiconductor body ( 1 ), wherein - each stripe emitter ( 10 ) a contact surface ( 3 ) is uniquely assigned, - via the contact surfaces ( 3 ) during operation of the semiconductor laser ( 100 ) Current in at least one of the strip emitters ( 10 ), and - at least two of the strip emitters ( 10 ) are electrically operated separately. Edge-emitting semiconductor laser ( 100 ) according to claim 1, wherein at least one strip emitter ( 10 ) is electrically uncontacted. Edge-emitting semiconductor laser ( 100 ) according to claim 1 or 2, with at least two connection surfaces ( 4 ), which on the outer surface ( 12 ) of the semiconductor body ( 1 ), each pad ( 4 ) a contact surface ( 3 ) and with this contact surface ( 3 ) is electrically connected, and the pads ( 4 ) for electrical contacting of the contact surfaces ( 3 ) serve. Edge-emitting semiconductor laser ( 100 ) according to the preceding claim, in which each pad ( 4 ) with its associated contact surface ( 3 ) is directly connected. Edge-emitting semiconductor laser ( 100 ) according to the preceding claim, in which at least one connection surface ( 4 ) on the outer surface ( 12 ) of the semiconductor body ( 1 ) in the transverse direction ( 101 ) between adjacent contact surfaces ( 3 ) is arranged. Edge-emitting semiconductor laser ( 100 ) according to claims 3 to 5, in which the outer surface ( 12 ) at least one region between in the transverse direction ( 101 ) adjacent contact surfaces ( 3 ), which is free from the connection surfaces ( 4 ). Edge-emitting semiconductor laser ( 100 ) according to one of Claims 3 to 6, in which at least one connection surface ( 4 ) and an unassigned contact surface ( 3 ) at least one overlap area ( 24 ), in which the connection surface ( 4 ) and the contact area ( 3 ) in the vertical direction (V) at least in places overlap, wherein in the vertical direction (V) between the pad ( 4 ) and the contact surface ( 3 ) in the overlap area ( 24 ) at least in places an electrical insulation ( 41 ) is arranged. Edge-emitting semiconductor laser ( 100 ) according to claim 3, wherein each pad ( 4 ) via at least one contact bridge ( 5 ) with its associated contact surface ( 3 ) is electrically connected. Edge-emitting semiconductor laser ( 100 ) according to one of Claims 3 to 8, in which at least two connection surfaces ( 4 ) on the same side of a contact surface ( 3 ) on the outer surface ( 12 ) of the semiconductor body ( 1 ) are arranged. Edge-emitting semiconductor laser ( 100 ) according to one of claims 8 or 9, wherein at least one contact web ( 5 ) and a the contact bridge ( 5 ) unassigned contact surface ( 3 ) at least one further overlap area ( 25 ), in which the contact bridge ( 5 ) and the contact area ( 3 ) in the vertical direction (V) at least in places overlap, wherein in the vertical direction (V) between the contact bridge ( 5 ) and the contact surface ( 3 ) in the further overlap area ( 25 ) at least in places a further electrical insulation ( 42 ) is arranged. Edge-emitting semiconductor laser ( 100 ) according to one of claims 8 to 10, wherein at least one contact bridge ( 5 ) has an interruption through which the electrically conductive connection between a connection surface ( 4 ) and its associated contact surface ( 3 ) is predetermined. Edge-emitting semiconductor laser ( 100 ) according to one of the preceding claims, in which at least two of the strip emitters ( 10 ) resonator lengths of different lengths ( 34 ) exhibit. Edge-emitting semiconductor laser ( 100 ) according to one of the preceding claims, in which the semiconductor body ( 1 ) based on a III-nitride semiconductor material. Edge-emitting semiconductor laser ( 100 ) according to one of the preceding claims, in which rib depths (RT) of 101 ) juxtaposed strip emitters ( 10 ) differ by at least 10 nm. Edge-emitting semiconductor laser ( 100 ) according to one of the preceding claims, in which rib widths (RB) of transverse ( 101 ) juxtaposed strip emitters ( 10 ) differ by at least 100 nm.

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