METHOD FOR ADJUSTING THE MAGNETIZATION IN AT LEAST ONE REGION OF A SEMICONDUCTOR DEVICE

A method for magnetizing at least one region of a semiconductor device. The method includes: heating at least one antiferromagnetic layer of the at least one region to at least a threshold temperature of the antiferromagnetic layer using a first light beam and applying a first external magnetic field in a first direction of the magnetization to be produced in a ferromagnetic layer of the at least one region at least during a cooling of the antiferromagnetic layer of the at least one region which was previously heated at least to the threshold temperature. Before heating at least the antiferromagnetic layer of the at least one region to at least the threshold temperature of the antiferromagnetic layer, at least one absorption and/or antireflection layer is disposed on and/or in at least one first subvolume of the semiconductor device which includes the at least one region.

FIELD

The present invention relates to a method for adjusting the magnetization in at least one region of a semiconductor device. The present invention also relates to a semiconductor device.

BACKGROUND INFORMATION

PCT Patent Application No. WO 02/082111 A1 describes a method for adjusting a magnetization in a layer arrangement comprising an antiferromagnetic layer and an adjacent ferromagnetic layer, in which at least the antiferromagnetic layer is heated to above a threshold temperature by local irradiation using a laser and, after the threshold temperature is exceeded and during a subsequent cooling of at least the antiferromagnetic layer, an applied external magnetic field can be used to produce a desired direction of magnetization in the ferromagnetic layer.

SUMMARY

The present invention provides a method for adjusting the magnetization in at least one region of a semiconductor device and a semiconductor device.

An example embodiment of the present invention makes it possible to adjust the magnetization of a ferromagnetic layer in at least one region of a semiconductor device in that the absorption of the electromagnetic radiation of the light beam used to heat at least one antiferromagnetic layer of the at least one region is increased in a targeted manner in the at least one region by means of at least one absorption and/or antireflection layer, as a result of which unfavorable concomitant heating of at least one neighboring region of the at least one region is limited/prevented. Damage to the semiconductor device due to overheating the at least one neighboring region when carrying out the alignment of the magnetization can thus be avoided, while at least the antiferromagnetic layer of the at least one region can nonetheless be reliably heated to at least its threshold temperature.

As will become evident from the following description, the present invention can also be used to configure any number of different magnetization directions (pinning directions) in the respective regions of the semiconductor device provided for this purpose. The thus realized magnetization directions can then be used as sensing directions. The present invention can thus also be used to produce a semiconductor device that is used as a sensor device. With appropriate interconnection, the combination of different sensing directions in a semiconductor component can be used to form a 2D-Sensor (independent sensing in x and y direction) or, possibly after integration of a suitable flux diverter, to form a 3D-Sensor (x, y and z). Due to its unlimited number of sensing directions, the thus obtained sensor device has a comparatively high sensitivity and reliable resistance to interference fields. The sensing directions can specifically also include pairwise opposite sensing directions. Because of its unlimited number of sensing directions, such a sensor device can in particular also be configured for 360° angle sensing. A sensor device created by means of the present invention can, for instance, be used to realize a tunneling magnetoresistance (TMR) sensor or a giant magnetoresistance (GMR) sensor.

According to an example embodiment of the present invention, the at least one absorption and/or antireflection layer is preferably disposed on and/or in at least the first subvolume of the semiconductor device such that absorption of the first light beam in at least the part of the at least one region is increased by means of the at least one absorption and/or antireflection layer. This achieves a targeted increase in the absorption and/or heat conduction of the energy of the first light beam at/to the antiferromagnetic layer of the at least one region, and thus brings about a targeted heating of the antiferromagnetic layer of the at least one region to at least its threshold temperature while avoiding/limiting undesired concomitant heating of the at least one neighboring region of the at least one region.

According to an example embodiment of the present invention, during the heating of at least the antiferromagnetic layer of the at least one region to at least the threshold temperature of the antiferromagnetic layer using the first light beam, the first light beam is preferably aligned such that the first light beam hits a surface of at least the first subvolume of the semiconductor device which comprises the at least one region or at least one outer layer which covers the surface, and where at least a first partial area of the surface is covered with the at least one absorption and/or antireflection layer while at least a second partial area of the surface is kept free of or not covered by the at least one absorption and/or antireflection layer. The here-described embodiment of the method achieves a targeted increase in the absorption of the electromagnetic radiation of the first light beam in the at least one region while at the same time avoiding/limiting undesired concomitant heating of at least one neighboring region adjoining the at least one second partial area of the surface.

As an advantageous further development of the method of the present invention, in which, during the heating of at least the antiferromagnetic layer of the at least one region to at least the threshold temperature of the antiferromagnetic layer using the first light beam, the first light beam is aligned such that the first light beam hits the surface of the first subvolume of the semiconductor device which comprises the at least one region or the at least one outer layer which covers the surface, while the first light beam is dimmed or suppressed on a second subvolume of the semiconductor device by beam shaping the first light beam, the following method steps can be carried out after the first external magnetic field has been applied: heating at least one antiferromagnetic layer of at least one further region in the second subvolume of the semiconductor device to at least a threshold temperature of the antiferromagnetic layer of the at least one further region using a second light beam such that at least one subbeam of the second light beam is absorbed by at least a part of the at least one further region and converted into heat, as a result of which at least the antiferromagnetic layer of the at least one further region is heated, while the second light beam is dimmed or surpressed on the first subvolume of the semiconductor device by beam shaping the second light beam, and applying a second external magnetic field in a second direction different from the first direction at least during a cooling of the antiferromagnetic layer of the at least one further region which was previously heated at least to the threshold temperature, as a result of which a ferromagnetic layer of the at least one further region is magnetized. As will become evident from the following description, the here-described further development of the method can be used to achieve any number of different magnetization directions (pinning directions) in the respective regions of the semiconductor device.

According to an example embodiment of the present invention, a silicon nitride layer, a layer combination of at least one silicon nitride layer and at least one silicon oxide layer (36b), a titanium nitride layer, a titanium tungsten nitride layer, a tantalum layer, a tantalum nitride layer and/or a tungsten layer can be arranged on and/or in at least the first subvolume of the semiconductor device as the at least one absorption and/or antireflection layer, for instance. It is thus possible to use a variety of materials frequently already used in semiconductor technology for the at least one absorption and/or antireflection layer. As will further be evident from the following description, the at least one absorption and/or antireflection layer can also be used for other purposes after magnetization has been carried out using the method described here. It should also be noted that the examples for the at least one absorption and/or antireflection layer described here are not to be interpreted as exhaustive.

In particular, according to an example embodiment of the present invention, at least one dielectric antireflection layer can be disposed on and/or in at least the first subvolume of the semiconductor device as the at least one absorption and/or antireflection layer. The at least one dielectric antireflection layer ensures a desired increase in the absorption of electromagnetic radiation specifically in the at least one respective region to be heated.

According to an example embodiment of the present invention, the above-described advantages are also ensured with a semiconductor device having at least one region comprising a respective antiferromagnetic layer and a ferromagnetic layer with a magnetization of the ferromagnetic layer, wherein the semiconductor device comprises at least one absorption and/or antireflection layer on and/or in at least one subvolume of the semiconductor device which comprises the at least one region.

Preferably, according to an example embodiment of the present invention, at least a first partial area of a surface of at least the subvolume of the semiconductor device which comprises the at least one region is covered with the at least one absorption and/or antireflection layer while at least a second partial area of the surface is not covered by the at least one absorption and/or antireflection layer.

According to an example embodiment of the present invention, the at least one absorption and/or antireflection layer can include a silicon nitride layer, a layer combination of at least one silicon nitride layer and at least one silicon oxide layer, a titanium nitride layer, a titanium tungsten nitride layer, a tantalum layer, a tantalum nitride layer and/or a tungsten layer, for instance. Alternatively or additionally, the at least one absorption and/or antireflection layer can also include at least one dielectric antireflection layer.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

FIGS.1A-1Cshow a flow chart and schematic illustrations to explain a first embodiment of the method for adjusting the magnetization in at least one region of a semiconductor device. When carrying out the method described in the following, which is shown inFIG.1Aas a flow chart, at least one region10of a semiconductor device12is magnetized, wherein the at least one region10of the semiconductor device12comprises a respective antiferromagnetic layer10aand a ferromagnetic layer10b. Even though this is not shown inFIGS.1B and1C, the antiferromagnetic layer10aand the ferromagnetic layer10bare disposed relative to one another such that, at least at a temperature of the antiferromagnetic layer10aand the ferromagnetic layer10bbelow a (later discussed) threshold temperature, a so-called “exchange bias effect” occurs, which brings about the magnetization of the ferromagnetic layer10bto align according to the magnetization at the boundary surface of the antiferromagnetic layer10a. An outer surface of the antiferromagnetic layer10acan be in mechanical contact with an outer surface of the ferromagnetic layer10b, for example. Alternatively, however, there may also be at least one intermediate layer between the antiferromagnetic layer10aand the ferromagnetic layer10b.

The antiferromagnetic layer10ais at least partly (preferably completely) made of at least one antiferromagnetic material, such as nickel oxide, iridium manganese (IrMn) and/or platinum manganese (PtMn). However, the examples listed here for the at least one antiferromagnetic material are not to be interpreted as exhaustive. The ferromagnetic layer10bcorrespondingly preferably comprises at least one ferromagnetic material or hard magnetic material. Specifically, the ferromagnetic layer10bcan include cobalt, iron, nickel, platinum, palladium, and/or boron (B). The antiferromagnetic layer10aand/or the ferromagnetic layer10bcan each also be a layer stack. The ferromagnetic layer10bcan be a layer stack consisting of at least two hard magnetic layers with a respective a non-magnetic layer between two adjacent hard magnetic layers, for instance. The at least one non-magnetic layer of the layer stack can include ruthenium (Ru), for example.

The alignment of the magnetization of the ferromagnetic layer10baccording to the magnetization at the boundary surface of the antiferromagnetic layer10abrought about by the exchange bias effect can also be referred to as a “pinning” of the ferromagnetic layer10b. The threshold temperature is the temperature at/above which the antiferromagnetic material loses its ability to “pin” the ferromagnetic layer10b. The threshold temperature is therefore often also referred to as a blocking temperature. The threshold temperature depends on the at least one antiferromagnetic material of the antiferromagnetic layer10aand is therefore referred to in the following as the threshold temperature of the antiferromagnetic layer10a.

The magnetization of the at least one region10of the semiconductor device12brought about with the method described here is to be understood as an alignment of the direction of the magnetization/magnetization direction of the ferromagnetic layer10b, in particular in accordance with a given target magnetization direction. To achieve the desired magnetization of the ferromagnetic layer10bof the at least one region10, it is advantageous to “cancel” the exchange bias effect by briefly heating at least the antiferromagnetic layer10aof the at least one region10to at least the threshold temperature of the antiferromagnetic layer10a.

Using the method described in the following, the antiferromagnetic layer10aof the at least one region10can be specifically heated to at least the threshold temperature of the antiferromagnetic layer10aby means of a light beam14:

For this purpose, a method step S1 is carried out before the antiferromagnetic layer10aof the at least one region10is heated to at least the threshold temperature of the antiferromagnetic layer10aby means of a light beam14. In the method step S1, at least one absorption and/or antireflection layer16is disposed on and/or in at least a first subvolume12aof the semiconductor device12. As can be seen inFIG.1C(sectional view), the first subvolume12aof the semiconductor device12incudes the at least one region10. Advantageous examples of the at least one absorption and/or antireflection layer16will be discussed below.

In a method step S2 carried out after the method step S1, at least the antiferromagnetic layer10aof the at least one region10is heated to at least the threshold temperature of the antiferromagnetic layer10a. For this purpose, the light beam14is directed onto the semiconductor device12such that at least one subbeam of the first light beam14is absorbed by at least a part of the at least one region10and converted into heat, as a result of which at least the antiferromagnetic layer10ais heated.

The at least one absorption and/or antireflection layer16brings about an increased absorption of electromagnetic radiation of the light beam14by at least a part of the at least one region10during the execution of the method step S2 and, due to heat conduction, also a heating of the antiferromagnetic layer10aof the at least one region10. In other words, the at least one absorption and/or antireflection layer16brings about increased absorption by the at least one region10or an increase in the absorbance of the at least one region10. The at least one absorption and/or antireflection layer16thus also affects a temperature distribution in a light incidence region A of the light beam14such that, above all, a local temperature of the antiferromagnetic layer10aof the at least one region10reaches or exceeds the threshold temperature, while at least one neighboring region18adjacent to the at least region10is heated less than or at least not more than the antiferromagnetic layer10aof the at least one region10despite its position in the light incidence region A of the light beam14.

This achieves a targeted heating of the antiferromagnetic layer10aof the at least one region10to at least its threshold temperature while avoiding/limiting concomitant heating of the at least one neighboring region18. Avoiding/limiting concomitant heating of the at least one neighboring region18makes it possible to prevent damage to the semiconductor device12resulting from overheating of the at least one neighboring region18. The achieved avoiding/limiting of the concomitant heating of the at least one neighboring region18also makes it possible to prevent heat transfer from the respective neighboring region18to a surrounding region of the semiconductor device12. The advantages of prevented heat transfer will be discussed below.

In a further method step S3, an external magnetic field is applied, the direction of which determines the magnetization (i.e. its magnetization direction) to be effected in the ferromagnetic layer10bof the at least one region10. The method step S3 takes place at least during a cooling of the antiferromagnetic layer10aof the at least one region10which was previously heated at least to the threshold temperature. The method step S3 can, of course, also be carried out when at least the threshold temperature has already been reached at least at the antiferromagnetic layer10aof the at least one region10. The application of the external magnetic field can conveniently also be started prior to starting method step S2, because the heating of at least the antiferromagnetic layer10aof the at least one region10at least to the threshold temperature typically takes only one or a few laser pulse lengths of a few nanoseconds, for example.

Advantageous ways of carrying out the here-described method are discussed in the following:

The light beam14used to carry out method step S2 can be aligned to the semiconductor device12with the aid of a mask, for example. The method step S2 can alternatively also be carried out using a light beam14with a comparatively small beam diameter, which either sweeps over the surface14or scans it in successive pulses. The light beam14can be either a pulsed or a continuous light beam14. The light source emitting the light beam14can be a laser, for instance. The light incidence region A of the light beam14on the semiconductor device12can have a maximum extent of between 5 μm (microns) and 200 μm (microns), for example.

As can be seen inFIG.1C, in the embodiment of the method described here, the light beam14is aligned during method step S2 such that the light beam14hits a surface S of at least the first subvolume12a. In order to bring about the desired targeted heating of the antiferromagnetic layer10aof the at least one region10to at least the threshold temperature by means of the light beam14, at least a first partial area20aof the surface S is covered with the at least one absorption and/or antireflection layer16during execution of the method step S1, while at least a second partial area20bof the surface S is kept free of or not covered by the at least one absorption and/or antireflection layer16. Because a desired position and a desired shape of the at least one absorption and/or antireflection layer16can be maintained with greater precision than the light beam14can be limited to a desired maximum light incidence area on the surface S, the here-described configuration of the at least one absorption and/or antireflection layer16while keeping free/not covering the at least one second partial surface20bof the surface S makes it possible to achieve an even more targeted heating of the antiferromagnetic layer10aof the at least one region10to at least the threshold temperature while avoiding/preventing concomitant heating of the at least one neighboring region18. InFIG.1C, it can be seen that the light incidence region A of the light beam14on the surface S can easily also cover neighboring regions18adjacent to the at least one region10without undesirable overheating of said neighboring regions.

In the embodiment of the method described here, as an example, the semiconductor device12comprises a plurality of top electrodes22aand a plurality of bottom electrodes22b, and the regions10to be magnetized all lie between a respective top electrode22aand a respective bottom electrode22b. The top electrodes22aand the bottom electrodes22bare each made of at least one metal, in particular tantalum, ruthenium, tantalum nitride and/or copper. However, the materials for the electrodes22aand22blisted here are to be interpreted merely as examples. The top electrodes22aand the bottom electrodes22bare furthermore embedded in an insulating layer24such that the individual areas10to be magnetized are properly interconnected. The insulating layer24is made of silicon dioxide and/or silicon oxide, for example.

When designed as a tunnel magnetic sensor, a tunnel barrier and a soft magnetic layer are disposed between the top electrodes22aor the bottom electrodes22band the ferromagnetic layer10bas well. The tunnel barrier can be a very thin magnesium oxide or aluminum oxide layer, for instance. The soft magnetic layer substantially aligns its magnetization to the external magnetic field. The resistance of the tunnel barrier changes with the angle between the magnetization direction of the adjoining hard and soft magnetic layers. The sensing direction is the fixed magnetization direction of the ferromagnetic layer10aadjoining the tunnel barrier which was defined by the pinning process. The change in the resistance of the tunnel barrier can be detected by means of a current flow through the layer system and can be used as a sensor signal.

Advantageously, the only absorption and/or antireflection layer16of the embodiments ofFIGS.1A to1Cis a silicon nitride layer. Because the surface S hit by the light beam14during the execution of the method step S2 consists of the silicon dioxide of the insulating layer24and the metal of the top electrodes22a, the silicon nitride-metal boundary surfaces28between the top electrodes22aand the absorption and/or antireflection layer16lead to an increase in the absorption of electromagnetic radiation of the light beam14and increased heat conduction in the regions10. Unlike the silicon nitride-metal boundary surfaces28, this effect does not occur on the at least one second partial area20bof the surface S not covered by the absorption and/or antireflection layer16. At the at least one silicon nitride-silicon dioxide boundary surface30between the insulating layer24and the absorption and/or antireflection layer16, the layer thicknesses of the layers16and d1can be optimized such that the light radiation absorbed by the bottom electrode approximates the light radiation absorbed in the regions28. The thus generated heat energy can then contribute to the heating of the regions10through heat conduction via the bottom electrode. The silicon nitride-metal boundary surfaces28created by the absorption and/or antireflection layer16thus selectively increase the absorption of the regions10while limiting the absorption of the at least one neighboring region18. The absorption and/or antireflection layer16made of silicon nitride can moreover remain in use after the here-described method is carried out as a dielectric passivation layer.

Local layer thicknesses d1and d2of the insulating layer24aligned perpendicular to the light incidence region A of the light beam14on the surface S can additionally also be used during the execution of the method step S2 to bring about a desired temperature distribution. The extent of the layer16and the local layer thickness d1or d2of the insulating layer24can in particular be selected such that either outer regions of the antiferromagnetic layer10aof the at least one region10are also reliably heated to at least the threshold temperature, or that absorption is reduced in these regions.

FIG.2shows a schematic illustration to explain a second embodiment of the method for adjusting the magnetization in at least one region of a semiconductor device.

In the method shown schematically byFIG.2, a metal layer or metallic connecting layer32is disposed on and/or in at least the first subvolume12aof the semiconductor device12as the at least one absorption and/or antireflection layer16and32in addition to the silicon nitride layer16. The metal layer32can, for example, be a titanium nitride layer, a titanium tungsten nitride layer, a tantalum layer, a tantalum nitride layer, a tungsten layer, and/or some other layer that has an absorbing effect in the used wavelength range of the used radiation14. The metal layer32can be 50 to 100 nm (nanometers) thick, for instance.

As an example, in the embodiment described here, the metal layer32lies between the surface S and the silicon nitride layer16and covers the top electrodes22a, wherein shapes of cover surfaces structured out of the metal layer32correspond (not necessarily identically) to a respective cross-section of the top electrode22acovered with it within the surface S. The additional use of the metal layer32makes it possible to increase the absorption of electromagnetic radiation of the light beam14at the silicon nitride-metal boundary surfaces28even more, while limiting the absorption of the at least one neighboring region18.

With regard to the further method steps of the method ofFIG.2and their advantages, reference is made to the description ofFIGS.1A to1C.

FIG.3shows a schematic illustration to explain a third embodiment of the method for adjusting the magnetization in at least one region of a semiconductor device.

In the embodiment ofFIG.3, the light beam14for heating at least the antiferromagnetic layer10aof the at least one region10to at least the threshold temperature is aligned such that the light beam14hits at least one outer layer34covering the surface S. The outer layer34is a silicon nitride layer, for example, with which the at least one absorption and/or antireflection layer32formed on the surface S is covered.

The (only) absorption and/or antireflection layer32is a metal layer or metal connecting layer32, such as a titanium nitride layer, a titanium tungsten nitride layer, a tantalum layer, a tantalum nitride layer, a tungsten layer, and/or some other layer that has an absorbing effect in the used wavelength range of the used radiation14. Cover surfaces structured out of the metal layer32moreover cover only the top electrodes22a, in that a respective shape of the cover surfaces corresponds to a respective cross-section of the top electrode22acovered with it within the surface S. In the embodiment ofFIG.3, too, the absorption of electromagnetic radiation of the light beam14at the silicon nitride-metal boundary surfaces28is increased while limiting the absorption of the at least one neighboring region18.

With regard to the further method steps of the method ofFIG.3and its advantages, reference is made to the description ofFIGS.1A-1C and2.

FIG.4shows a schematic illustration to explain a fourth embodiment of the method for adjusting the magnetization in at least one region of a semiconductor device.

The method ofFIG.4differs from the embodiment ofFIGS.1A-1Conly in that the at least one second partial area20bof the surface S is not kept free of and/or uncovered by the at least one absorption and/or antireflection layer16during execution of the method discussed here. However, as can be seen inFIG.4, the absorption and/or antireflection layer16made of silicon nitride brings about an increase in the absorption and/or the heat conduction of the energy of the light beam14at/to the antiferromagnetic layer10aof the at least one region10in the method discussed here, too (compared with the at least one silicon nitride-silicon dioxide boundary surface30between the insulating layer24and the absorption and/or antireflection layer16). In this embodiment, the thicknesses of the dielectric layers can be coordinated with one another and to the wavelength of the used radiation14such that the absorption of the radiation is advantageously greater in the regions10than in the adjoining regions.

With regard to the further method steps of the method ofFIG.4and their advantages, reference is made to the description ofFIGS.1A to3.

FIG.5shows a schematic illustration to explain a fifth embodiment of the method for adjusting the magnetization in at least one region of a semiconductor device.

In the embodiment shown schematically byFIG.5, at least one dielectric antireflection layer36is disposed on and/or in at least the first subvolume12aof the semiconductor device12as the at least one absorption and/or antireflection layer36. Merely as an example, in the embodiment described here, the at least one dielectric antireflection layer36comprises a first silicon nitride layer36awhich covers the at least one first partial area20aof the surface S, a silicon dioxide layer36bwhich covers the first silicon nitride layer36aand a second silicon nitride layer36cwhich covers the silicon dioxide layer36b. Other dielectric layers with different refractive indices can also be used instead of the silicon nitride and silicon oxide layers.

With regard to the further method steps of the method ofFIG.5, and their advantages, reference is made to the description ofFIGS.1A-1C to4.

FIGS.6A and6Bshow a flow chart and a schematic illustration to explain a sixth embodiment of the method for adjusting the magnetization in at least one region of a semiconductor device.

In the method shown schematically byFIGS.6A and6B, the method step S1 is carried out first, wherein the at least one absorption and/or antireflection layer16,32and/or36is disposed not only on and/or in at least the first subvolume12a, but also on and/or in a second subvolume12band a third subvolume12cof the semiconductor device12. Next, the method step S2 is carried out, wherein, during the heating of at least the antiferromagnetic layer10aof the at least one region10to at least the threshold temperature of the antiferromagnetic layer10ausing the first light beam14, the first light beam14is aligned such that the first light beam14hits the surface S of the first subvolume12awhich comprises the at least one region10or the at least one outer layer34which covers the surface S, while the first light beam14is dimmed by the second subvolume12band the third subvolume12cby beam shaping the first light beam14.

After the application of the first external magnetic field B1in method step S3, further method steps are carried out:

In a method step S2′, at least one antiferromagnetic layer10a′ of at least one further region10′ in the second subvolume12bis heated to at least a threshold temperature of the antiferromagnetic layer10a′ of the at least one further region10′ by means of a second light beam14′ in that at least one subbeam of the second light beam14′ is absorbed by at least a part of the at least one further region10′ and converted into heat, so that at least the antiferromagnetic layer10a′ of the at least one further region10′ is heated, while the second light beam14′ is dimmed or suppressed on the first subvolume12aand the third subvolume12cby beam shaping the second light beam14′. In addition, as method step S3′, a second external magnetic field B2is applied in a second direction different from the first direction, at least during a cooling of the antiferromagnetic layer10a′ of the at least one further region10′ which was previously heated at least to the threshold temperature, as a result of which a ferromagnetic layer10b′ of the at least one further region10′ is magnetized and fixed (pinned) in this magnetization direction during the cooling process of the antiferromagnetic layer.

Optionally, in a method step S2″, at least one antiferromagnetic layer10a″ of at least one further region10″ in the third subvolume12ccan then be heated by means of a third light beam14″ to at least a threshold temperature of the antiferromagnetic layer10a″ of the third subvolume12c. As a method step S3″, at least during cooling of the antiferromagnetic layer10a″ of the third subvolume12cwhich was previously heated at least to the threshold temperature, a ferromagnetic layer10b″ of the at least one further region10″ can be magnetized by means of a third external magnetic field B3in a third direction different from the first direction and the second direction. The advantageous magnetization of the regions10,10′ and10″ in different directions is possible because of the advantageous avoidance/limitation of concomitant heating of at least one neighboring region18and the thus prevented heat transfer from the respective neighboring region18despite the relatively close proximity of the regions10,10′ and10″.

Steps S2 and S3 can be repeated as often as necessary in different regions10with different or the same magnetic directions.

With regard to the further method steps of the method ofFIGS.6A and6B, and their advantages, reference is made to the description ofFIGS.1A to5.

The methods discussed above can also be referred to as pinning processes. They can be carried out at the end of the production of the respective semiconductor devices12, for instance. Compliance with special protective measures, such as carrying out the respective procedure in a clean room, is not necessary. Each one of the above-described methods can alternatively also be carried out during the production of the respective semiconductor device12. In that case, the pinning process can be followed by further steps for interconnecting and contacting the sensor regions and/or to implement further functions.

FIGS.1A to6Beach also show a semiconductor device12with at least one region10comprising a respective antiferromagnetic layer10aand a ferromagnetic layer10bwith a magnetization of the ferromagnetic layer10b. The semiconductor device12additionally also comprises at least one absorption and/or antireflection layer16,32and/or36on and/or in at least one subvolume12aof the semiconductor device12which comprises the at least region10. At least a first partial area20aof a surface S of at least the subvolume12aof the semiconductor device12which comprises the at least one region10can be covered with the at least one absorption and/or antireflection layer16,32and/or36, for example, while at least a second partial area20bof the surface S is not covered by the at least one absorption and/or antireflection layer16,32and/or36. Examples of the at least one absorption and/or antireflection layer16,32, and/or36have already mentioned above. Each of the semiconductor devices12shown inFIG.1A to6Bcan advantageously be used as a sensor device. The at least one sensor device of the respective semiconductor device/sensor device12is defined by the at least one magnetization direction of the regions10,10′,10″ and possible further regions10xof the respective sensor device12. The regions10,10′ and10″ and possible further regions10xcan be interconnected to form at least one Wheatstone bridge, for instance. The respective semiconductor device/sensor device12can, for example, be a tunneling magnetoresistance (TMR) sensor or a giant magnetoresistance (GMR) sensor.