Patent Description:
Semiconductor and compound semiconductors components for a variety of appliances, such as power train inverters, produce heat, and receive heat from other sources, which may raise the temperature of the semiconductor component. The temperature of the semiconductors forms one of the limits for wider system operation as excess temperature leads to catastrophic failure, but approaching the limit is often desirable from a performance perspective. Further, individual semiconductors are often used in groups and may not see identical current loading nor heating. There is therefore a demand for measuring or monitoring the temperature of critical semiconductor components, both individually and in groups. Operation of a semiconductor component may also be limited by a current running therethrough, so that knowledge of the current is also highly useful.

Known methods for measuring or monitoring the temperature of a semiconductor component, e.g. of a power module, suffer from the need to isolate temperature sensing elements from the high voltage present. , the placement of temperature sensors in the prior art is associated with gaps in thermal paths, leading to a low responsiveness to fast temperature rises. A low responsiveness to these fast transient temperature changes significantly limits the accuracy and utility of the measurement. The more accurately temperature is measured, the more accurately power draw of a specific device can be interpreted. Once a specific device temperature is known, conclusions can be drawn about device health and performance limits, moreover this can be specific to the exact build.

It is known e.g. from <CIT> that SiC dies can emit light by electroluminescence. The emission is temperature dependent allowing interpolation of one from the other. As a result of the photoluminescence or electroluminescence effect, SiC components in power module assemblies such as largely used in vehicles like automobiles emit light. Due to the encapsulation required for high voltage operation, the light emission however is largely unobserved.

<CIT> and <CIT> disclose that detecting light emission of a SiC power device can be used for contact-less synchronous online detection of junction temperature and current of the silicon carbide power device working in high-temperature, high-voltage and high-current application occasions, with high precision and real-time performance. The measurement is done by a photoelectric detection circuit which receives the light from a light guide which is made of low-loss silica fibre. Fibre optics are however delicate to handle and connect, designed for high-intensity light sources, and sensitive to vibrations which usually occur in automobile appliances and other fields. In particular, a slight deviation in an angle or position under which a light guide is situated with respect to a light source can drastically change the amount of light coupled into the light guide. Similar problems can occur at the light emitting side of the light guide where the light is coupled out to be received by an optical sensor. Under strong vibrations, such deviations can occur which might be small but still have a strong impact on the light received, transported, and emitted by a light guide, thereby affecting reliably of light measurement, and conclusion drawn from such measurement. Moreover, a light receiving surface of a light guide is usually small, as it is adapted to receive strong light signals such as from a laser or LED. The photoluminescence or electroluminescence effects of an SiC die however are a side effect which is not very intense, as compared with common fibre optic laser light sources which are designed for high output. Also, the light emission of an SiC component is not concentrated but is distributed over a broad region all along a side surface of the component. For effectively collecting light of a relatively weak and dispersed source into a light guide, highly complex coupling setup would have to be developed and used. The mounting of such coupling setup with the die and with the light guide must be made with high precision and typically comprises either a lens stack or a lensed fibre. A similar method of detecting light emission of semiconductor components for temperature and/or current monitoring is disclosed in <CIT>. Therefore, temperature measurement or current measurement based on a light output of an SiC component under strong vibrations such as in automotive appliances is neither reliable nor cost effective with the solutions available in the art.

A technical problem of the invention is to create a monitoring device and method which enables accurate, responsive and reliable measurement of temperature or current of a semiconductor component under high current load even under rough mechanical conditions by utilizing electroluminescence or photoluminescence effects of the semiconductor element while enabling easy manufacture and providing resilient structure, a semiconductor device including a semi-conductor component having such monitoring device, and a method for manufacturing the same.

The technical problem is solved by the features of the independent claims. Further developments and advantageous embodiments are set forth in the subclaims.

An aspect of the invention is a monitoring device for a semiconductor component for an automobile appliance under high current and/or voltage, said semiconductor component having a light emitting surface and emitting photons at the light emitting surface when biased or reverse-biased, by way of electroluminescence or photoluminescence, in an amount depending on a temperature of, and/or a current through the semi-conductor component and/or its gate voltage, wherein the semiconductor component comprises particularly silicon carbide, the monitoring device including a light pipe insert having a light receiving end or light capturing end and a light emitting end or light extraction end, the light pipe insert being formed and placed to receive photoluminescence light or electroluminescence light from the semiconductor component through a light receiving surface formed at the light receiving end to face at least part of the light emitting surface of the semiconductor component, and to conduct the received light to the light emitting end for detecting the temperature of the semi-conductor component and/or a current through the semiconductor component and/or a gate voltage of the semiconductor component through an optical sensor configured to be coupled to the light emitting end of the light pipe insert, wherein the light pipe insert comprises a light pipe body having a foot section at the light receiving end and a shaft section extending from the foot section to the light emitting end, and wherein the light pipe body is a solid monolithic body made of a transparent material such as a transparent polymer or a typical glass.

A light pipe is a rigid body which is easy and inexpensive to manufacture, to handle and to mount. It can have a relatively large light receiving surface which is able to collect light over an elongated area like the side surface of an SiC die. The position and orientation of the light pipe with respect to the die or a sensor is not that critical like with a fibre-type light guide which typically has a narrow depth-of-field, at least within the boundaries of deviations expectable by vibration and assembly-tolerances in an automobile appliance. A complex and fragile coupling setup is not needed at the light receiving end or the light emitting end of a light pipe. By use of a light pipe insert according to the invention therefore enables accurate, responsive and reliable measurement of temperature and/or current of a semiconductor component and/or its gate voltage under high current load even under rough mechanical conditions by utilizing electroluminescence or photoluminescence effects of the semiconductor element while enabling easy manufacture and providing resilient structure, allowing for an indirect measurement by sensing the photon output linked with the respective condition. It will be noted that the semiconductor component may be a compound semiconductor component. Also, these materials of polymer or typical glass are naturally insulating, retaining the isolating function of an encapsulant of the semiconductor component, while achieving light conducting functions.

The semiconductor component may have a flat top surface and one or more side surfaces which surround the top surface and extend from a top surface or top face of a substrate where the semiconductor component is provided. The semiconductor component may have the light emitting surface formed in at least one side surface of the semiconductor component,. That part of the light emitting surface of the semiconductor component facing the light receiving surface of the light pipe insert may be at a straight part or a curved part of one side surface or a corner part of two side surfaces of the semiconductor component.

In embodiments, the light pipe insert may have a back face opposite to the light receiving surface, the back face being formed, preferably curved, to reflect light incident from the light receiving surface to a light emitting surface or light extraction surface provided at the light emitting end of the light pipe insert.

In embodiments, the light pipe insert may have a bottom face extending from the light receiving surface, the bottom face including an abutment surface and at least one indent being formed, preferably curved, to reflect light incident from the light receiving surface in a generally vertical direction to a light emitting surface provided at the light emitting end of the light pipe insert. The abutment surface may be formed to abut a surface of a substrate where the semiconductor component is provided.

In embodiments, light reflecting surfaces of the light pipe insert may be formed, preferably curved, in a direction across a path of light incident from the light receiving surface to focus the light to a point or a confined region within a light emitting surface provided at the light emitting end of the light pipe insert.

In embodiments, the light pipe insert may have a reflective or mirror-coating or reflection-enhancing surface treatment to improve internal reflection. This can be limited to particular reflective surfaces or surface parts, and can help transmitting the light with minimum loss due to side emission or absorption. Where the light pipe body is cylindrical, the reflective treatment may be all over the side surfaces.

Also, the light pipe insert may have an opaque coating or surface treatment to prevent transmission of light at surfaces other than the light receiving surface or a light emitting surface provided at the light emitting end of the light pipe insert. This can be limited to particular surfaces or surface parts, and can help avoiding side emission of light as well as incidence of light from outside. Such opacitizing treatment may be applied in addition to a reflective treatment.

Moreover, the light pipe insert may have a glossy coating or surface treatment to improve transmission of light at the light receiving surface or the light emitting surface of the light pipe insert.

Moreover, the light pipe insert may have a reflective coating or surface treatment to increase internal reflection, and improve the transmission of light along the light pipe's transmission path.

Furthermore, the light pipe insert may have an optical element such as a spherical or aspherical or Fresnel lens surface or lens stack at the light emitting end which may help capturing, focusing, and directing the light at the light emitting end.

In embodiments, the foot section has a wider cross-sectional area than the shaft section. The foot section may be formed to rest on a top surface or top face of a substrate where the semiconductor component is provided. With a wider cross-sectional are, mounting stability may be improved. The foot section may for example be formed like a collar. The shaft section may have any useful shape, and may have a swept rectangular profile, polygon, circular, elliptical profile, to form a straight, angled or curved (in one or more dimensions) piece. A swept profile in the sense of this application is a profile which has a similar cross-section at any place cut, but may follow an arbitrary path.

Here, the foot section may partly overlap a top surface of the semiconductor component. In other words, the foot section may rest on both top surfaces of the substrate and the semiconductor component which improves rigidity and reliability of mount, and ensures constant positioning of the light pipe insert with respect to the semiconductor component so that the direction of incident light can be held constant. For providing the overlap, the foot section may form a step, and the vertical part of the step may include the light receiving surface of the light pipe insert.

A gap between the light receiving surface of the light pipe insert and the light emitting surface of the semiconductor component may be filled with a transparent or semi-transparent medium such as glue or silicone.

If the foot section of the light pipe insert is thermally deformable, the foot section may be adapted to the shape of the semiconductor component during mounting such that the aforementioned step and the light receiving surface are exactly adapted to the semiconductor component. Here, a temperature range of thermal deformability is preferably well beyond a temperature which is expected to occur during operation of the semiconductor component, and well beneath a temperature the semiconductor component can passively endure without damage.

The monitoring device may further comprise an optical sensor formed and arranged for receiving light from a light emitting end of the light pipe insert, and providing sensor signals related to the received light from the light pipe insert. The optical sensor may be placed directly at a light emitting end of the light pipe insert, or at a remote location with the light from the light pipe insert being led to the sensor by other means.

The monitoring device may also further comprise a control unit formed for receiving and interpreting the sensor signals from the optical sensor to provide a sensor value related to the temperature of or a current through the semiconductor component the light pipe insert is placed at.

A further aspect of the invention is a semiconductor device for an automobile appliance, the semiconductor device comprising:.

and wherein the semiconductor component is encapsulated by an insulation layer such that a shaft section of the light pipe insert extends through and out of the insulation layer.

Here, the optical sensor senses a photon output linked with the temperature and/or current and/or gate voltage, and detection of the temperature and/or current and/or gate voltage makes use of that linkage.

A further aspect of the invention is a method for manufacturing the afore-described semiconductor device, the method comprising:.

The invention will now be further described in view of exemplary embodiment, referring to the accompanying drawings. In the drawings,.

It will be noted that the drawings are schematic by nature and are made to illustrate preferred examples for embodying the invention, so that its concept can be understood.

A monitoring device <NUM> according to an exemplary embodiment is used at a semiconductor device <NUM> (<FIG>).

The semiconductor device <NUM> includes a semiconductor component <NUM> which is typically placed on a substrate <NUM>, and may have further electronic elements <NUM>. In some instances, the semi-conductor component <NUM> may be formed of or in the substrate <NUM> or be grown thereon. For the purposes of this description, a vertical direction z is defined to extend normal from a top face or top surface 4a of the substrate <NUM>. Likewise, directions x, y perpendicular to each other and to the vertical direction z are defined within the top surface 4a of the substrate <NUM> to complete a cartesian coordinate system xyz. The directions x, y are horizontal directions. Here, the direction x may be defined to face away from one side surface 3b of the semiconductor component <NUM> where a light pipe insert <NUM> is placed (which is described below), and the direction y is along that side surface 3b. Where the light pipe insert <NUM> is placed at a corner of two side surfaces 3b of the semiconductor component <NUM> (see e.g. cases i, iii, iv in <FIG>), both directions x, y may be defined to face away from either of these two side surfaces 3b. This definition of horizontal directions x,y and vertical direction z is a local definition with respect to the semiconductor device <NUM>, which is only for ease of explanation and is independent from an orientation of the semiconductor device <NUM> in a global space or environment.

The semiconductor component <NUM> has a top surface 3a facing in the vertical direction z, and a side surface 3b or several side surfaces 3b exposed from the top surface 4a of the substrate <NUM> to be accessible from a lateral side. The semiconductor component <NUM> is of a kind which exhibits an electroluminescence or photoluminescence effect such that it emits photons when biased (in case of a Diode) or reverse-biased (in case of a MOSFET). Typically such effect shows at a junction and in a region surrounding that junction which is addressed as a light emitting layer 3c. The light emitting layer 3c is exposed at each side surface 3b of the semi-conductor element <NUM> to form a light emitting surface <NUM> of the semiconductor component <NUM> (detail "A" in <FIG>). In other words, the light emitting surface <NUM> is a light emitting portion of the side surface 3b where the light emitting layer 3c is exposed. It will be noted that thickness of a top layer covering the light emitting layer 3c of the semiconductor component <NUM> is shown exaggerated in the drawing. The thickness of the light emitting layer 3c might vary substantially within the semiconductor component <NUM>. The top layer may e.g. be a passivation layer with metallised contacts on top. Light cannot transition though these layers due to thickness. The electroluminescence or photoluminescence effect on biasing or reverse-biasing is known to arise in direct bandgap semiconductor components made of SiC (silicon carbide), in particular SiC <NUM> or SiC <NUM> polytypes. The intensity of photon emission according to the electroluminescence or photoluminescence effect is a convolved response to temperature, current conditions and gate voltage (the latter for MOSFETs only). SiC is widely used in power modules such as power MOSFETs for a variety of appliances such as traction inverters for electric vehicles or switching power supplies. Vehicles may include automobiles, trucks, motorcycles, trains, cableways, marine vessels, aircrafts. In the present embodiment, the semi-conductor component <NUM> is an SiC power MOSFET in an inverter of an automobile. It is desirable to know the temperature of the semiconductor component <NUM> for reliable function while exploiting its boundaries of operation. It is also desirable to know a current which the semiconductor component <NUM> endures, for the same reasons and for controlling the semiconductor component <NUM>.

The monitoring device <NUM> of the present embodiment is provided for collecting the photons or at least a defined fraction of the photons emitted by the semiconductor component <NUM> due to the electroluminescence or photoluminescence effect, for thereby detecting the temperature of the semiconductor component <NUM> or a current through the semiconductor component <NUM>. For this purpose, the monitoring device <NUM> includes a light pipe insert <NUM> that is placed at the semi-conductor component <NUM>. The light pipe insert <NUM> includes a light pipe body <NUM>. The light pipe body <NUM> is formed to conduct incident light by inner reflection from a light capturing end or light receiving end <NUM> to a light extraction end or light emitting end <NUM>, see an exemplary light ray <NUM> in <FIG>. For optimizing a path of the light rays <NUM>, the light pipe body <NUM> may have a reflective structure such as a curvature <NUM>. The optimization of the path of the light rays <NUM> may refer to a minimum length and/or a minimum number of inner reflections.

The light pipe body <NUM> has a foot section <NUM> which abuts the semiconductor device <NUM>, in particular the top surface 4a of the substrate <NUM>, and a shaft section <NUM> which extends from the substrate <NUM>. The foot section <NUM> and the shaft section <NUM> may be integrally formed or connected with each other. The foot section <NUM> may include, be included, or coincide with the light receiving end <NUM> of the light pipe insert <NUM>.

In the present embodiment, the foot section <NUM> has a bottom face 9a which abuts the top surface 4a of the substrate <NUM>, and a front face 9b which faces the side surface 3b of the semiconductor component <NUM>. Thereby, the front face 9b of the foot section <NUM> includes the light receiving surface <NUM> of the light pipe insert <NUM>. It will be noted that in the enlarged detail "A" of <FIG>, a gap is shown between the front face 9b of the foot section <NUM> and the side surface 3b of the semiconductor component <NUM>. Even if such gap may be present, it is preferable that the front face 9b of the foot section <NUM> tightly abuts the side surface 3b of the semi-conductor component <NUM> to reduce phase interface transits of light. If a considerable gap is present, it is preferable that such gap is filled by a transparent filler or glue <NUM> (see <FIG>).

In the present embodiment, the shaft section <NUM> has a front face 10a generally facing in a direction toward the semiconductor component <NUM> in the horizontal plane xy, in particular in negative x direction, and a back face 10b generally facing away from the semiconductor component <NUM> in the opposite direction to the front face 10a. The front face 10a of the shaft section has an erect part 10c generally extending in the vertical direction z, and a slant part 10d inclined from the vertical direction z away from the semiconductor component <NUM>. The erect part 10c and the slant part 10d are flat. It will be noted that the front face 10a of the shaft section <NUM> is continuous with or coincides with the front face 9b of the foot section <NUM> to include the light receiving surface <NUM>. At the light emitting end <NUM>, a top end or top surface 10f of the shaft section <NUM> forms a light emitting surface <NUM> of the light pipe insert <NUM>. The back face 10b includes the curvature <NUM> in x-z cross section for optimizing inner reflection. In x-y cross section, the back face 10b is flat in this embodiment which however is not limiting the invention. The back face 10b may have a curvature also in a cross-section perpendicular to the x-z plane and normal to the x-z curvature for focusing rays of light within the light pipe body.

The shaft section <NUM> also has two lateral faces 10e (see <FIG>) facing perpendicular to the facing directions of the front face 10a and the back face 10b. In other words, the lateral faces 10c are parallel with each other and are generally flat. In the present embodiment, the light pipe body <NUM> has a width, i.e. is a distance between the two lateral surfaces 10e, smaller than a width of the semiconductor component <NUM>. This means that only a part of the light emitting surface <NUM> of the semiconductor component <NUM> is covered by the light receiving surface <NUM> of the light pipe insert <NUM>. This in turn means that all the width of the light receiving surface <NUM> of the light pipe insert <NUM> receives light rays which are generally parallel.

At the light emitting end <NUM> of the light pipe insert <NUM>, an optical sensor <NUM> may be coupled to receive light from a light emitting surface <NUM> of the light pipe body <NUM> (<FIG>). The optical sensor <NUM> may e.g. be a photodiode which has fast response time and low cost. The optical sensor <NUM> may be coupled to a processing unit <NUM> via data link <NUM>. The optical sensor <NUM> may be optionally be lensed or left un-lensed. A filter may optionally be provided before the sensor <NUM> to select for changes in specific wavelengths. Instead of directly coupling the sensor <NUM> with the light emitting end <NUM> of the light pipe insert <NUM>, light may optionally be brought to a preferred sensor location by free space optics, fibre optics, or a secondary light pipe system. The processing unit <NUM> may be a general purpose computer such as a laptop, desktop, phone or the like, or a special purpose control unit of an automobile, other vehicle, power plant or other appliance. The processing unit <NUM> may include a processor, data interface(s), permanent memory (ROM), working memory (RAM), flash memory, user interface(s), data reading/writing unit(s), and other elements as is generally known. The data link <NUM> may be a cable or wireless link and/or may be part of a bus structure, in particular field bus or vehicle bus such as a CAN bus, or the like. The optical sensor <NUM> is formed to output a sensor signal or sensor value in response to reception of light from the light pipe insert <NUM>. The processing unit <NUM> is formed to receive and interpret a sensor signal from the optical sensor <NUM> to provide a measuring value related to the temperature and/or the current through the semiconductor component and/or its gate voltage. The interpretation of sensor signals may make use of dependencies between an electroluminence amount and the properties or conditions mentioned above which are determined beforehand or are known from literature. Examples of such literature are [<NUM>] <NPL>, and [<NUM>] <NPL>.

In the semiconductor device <NUM>, the electronics parts on the substrate <NUM> can be arranged within a casing <NUM> (<FIG>). Besides the semiconductor component <NUM>, other parts can be arranged on the substrate <NUM>. In an exemplary embodiment which is neither limiting nor exhaustive, such other parts may include a power connecting unit <NUM> having a body part 21b and a number of connecting pins 21a-21d, conductive tracks 22a-22d of a high power wiring lines <NUM> leading from the power connecting unit <NUM> to the semiconductor component <NUM>, the conductive tracks 22a-22d representing e.g. a source track, a drain track, a gate track and a ground track, an RTD sensor <NUM>, a sensor connecting unit <NUM> having connection pins 24a, 24b and a body part 4c, conductive tracks 25a, 25b of a sensor wiring lines <NUM>, an so on. The RTD sensor <NUM> can be provided for measuring a temperature of the die based on a temperature-dependent resistance change, and can be used for calibrating the measurement via the light pipe insert <NUM> and the optical sensor <NUM>, for testing, or as a backup. Where the measuring characteristic of the optical measurement is reliably known, the RTD sensor <NUM> may also be omitted. It will be noted that the RTD sensor <NUM> will have a delay in measurement owing to the fact that a temperature change in the semiconductor component <NUM> needs some time to cause a temperature change in the substrate <NUM> beneath the RTD sensor <NUM>. In contrast, the change of light emission from the semiconductor component <NUM> will instantaneously follow a temperature change in the semiconductor component <NUM>, and thus can be detected instantaneously. The parts can be sealed by an insulating filler with only the connecting pins of the connecting units <NUM>, <NUM>, and the light emitting surface <NUM> of the light pipe insert <NUM> being exposed.

More than one semiconductor components <NUM> to be individually monitored may be played on one substrate <NUM> (see <FIG> where different kinds of light pipe inserts <NUM> are applied for purposes of illustration).

The shape and build of the light pipe insert <NUM> and light pipe body <NUM> may be varied in numerous ways.

For example, the light pipe body <NUM> may be a cuboid body having rectangular faces 10a, 10b, 10e, 10f, 9a (<FIG>). An indent <NUM> may be formed within the bottom face 9a, having a reflective geometry to enhance guiding a ray of light <NUM> which enters the light receiving surface <NUM> into the vertical direction z, to eventually reach the light emitting surface <NUM>. The indent <NUM> is formed only in a part of the bottom face 9a, such that abutment surfaces <NUM> remain for abutting the substrate. The indent <NUM> may be gently curved or polygonal, it may be curved generally in x-z cross section and may have or may not have a slight curvature also in a cross-section perpendicular to the x-z plane and normal to the x-z curvature. The indent <NUM> can be combined with any embodiment or variant shown or described herein.

The light pipe insert <NUM> may be formed and placed such that the foot section 9a partially covers the top surface 3a of the semiconductor component <NUM> (<FIG>).

In variants (i) to (vi) of light pipe inserts <NUM> shown in <FIG>, the light pipe body <NUM> may include:.

It will be noted that in each of cases (ii), (v), (vi) the light receiving surface <NUM> of the light pipe insert <NUM> faces a straight part of one side surface 3b of the semiconductor component <NUM>, and in each of cases (i), (iii), (iv) the light receiving surface <NUM> of the light pipe insert <NUM> faces a corner part where two side surfaces 3b of the semiconductor component <NUM> meet. All the forms are designed for optimization in view of conduction of light from the light receiving end <NUM> to the light emitting end <NUM> of the light pipe insert <NUM>, and stability of mount of the light pipe insert 7on the semiconductor device <NUM>.

Further variants of light pipe inserts <NUM> are shown in <FIG>, which may include:.

Many other variants and options are possible, such as the following:.

It will be noted that any variants or options may be mixed with each other and any embodiment shown or described herein, subject to feasibility and consistency.

A method for manufacturing the semiconductor device <NUM> having the monitoring device <NUM> includes at least the following steps:.

In a particular embodiment, the method may further include the step of gluing the light pipe insert <NUM> to the semiconductor device <NUM> by a glue <NUM> (see <FIG>). Here, a transparent glue <NUM> is preferably used at least in the region of a gap between the light receiving surface <NUM> of the light pipe insert <NUM> and the light emitting surface <NUM> of the semiconductor component <NUM>. Other parts of the light pipe insert <NUM>, in particular in a region between the light pipe insert <NUM> and the substrate <NUM>, could be fixed by an opaque glue or other methods such as e.g. friction welding. It will be understood that the opacity or transparency of the glue <NUM> refers to the cured state of the glue <NUM>.

In another embodiment, the method may include a pressing the light pipe insert <NUM> to the semiconductor device <NUM> in a pressing direction <NUM> such that a bottom face 9a of the foot section <NUM> of the light pipe body <NUM> has an overlap <NUM> with the top surface 3a of the semiconductor component <NUM> (<FIG>). Here, the bottom face 9a may even deform under the pressure to form a step <NUM> which perfectly fits the contour of the semiconductor component <NUM> in the overlap <NUM>, and the light receiving surface <NUM> of the light pipe insert <NUM> is formed by the forming of the step <NUM> to fit closely with the light emitting surface <NUM> of the semiconductor component <NUM> (<FIG>).

The embodiments of the method can also be combined. For example, the step <NUM> may be formed beforehand in the light pipe insert <NUM>. Here, a transparent glue <NUM> may be applied to fill possible gapes between the light pipe insert <NUM> and the semiconductor component <NUM>. On the other hand, the pressing may include a friction welding of the parts under pressure.

The method can also include a step of applying an insulation layer <NUM> such as a sealing upon the semiconductor device <NUM> which covers the substrate <NUM> and semiconductor device <NUM> as well as other electronic elements <NUM>, wirings <NUM>, <NUM> etc. while the light pipe insert <NUM> as well as e.g. connectors of connecting units <NUM>, <NUM> extend through the insulation layer <NUM> (<FIG>). The insulation layer <NUM> may typically be opaque.

The providing of the light pipe insert <NUM> may include a forming the light pipe body <NUM>, in particular by at least one of injection moulding, press-forming, die-cast moulding, gravity moulding, continuous casting (and chopping into parts of proper length), thermoforming, detailing, cutting, bending and/or twisting, finishing, surface treatment, mirror-coating, gloss-coating, opaque coating, polishing, roughening, assembling with other parts such as collar <NUM> or crosstalk barrier <NUM>, as far as not formed together with the light pipe body <NUM>.

The light pipe body <NUM> is formed as a solid monolithic body made of a transparent material such as a transparent polymer or a typical glass, including NBK7, Quartz, Sapphire, PE, PET, PMMA, Acrylic, PC, PETG, PVC, LSR, COCs, SAN, GPPS, ABS, MABS. Reflecting surfaces of the light pipe body <NUM> may be coated with a reflective or mirror coating. Other surfaces may be coated with a glossy coating or an opaque coating. A glossy coating can be useful e.g. for enhancing boundary transit at light receiving/emitting surfaces, and an opaque coating can be useful e.g. for shielding side emission or incidence from/into the light pipe body <NUM>.

The method preferably includes coupling a light sensor to the light emitting end <NUM> of the light pipe insert <NUM>, and connecting the optical sensor <NUM> with processing unit <NUM>.

Any light pipe insert <NUM> described and depicted in this application can be provided separately to be used in or as a monitoring device and can establish an individual embodiment of the invention, with or without further equipment such as optical sensor <NUM>, processing unit <NUM>, link <NUM>, or the like.

As said above, in a semiconductor device, multiple semiconductor components <NUM> may be provided, each being monitored by an individual light pipe insert <NUM>. Each light pipe insert <NUM> may be coupled to an individual optical sensor <NUM>. Alternatively, light emitted from multiple light pipe inserts <NUM> may be coupled to one optical sensor in parallel or serially or in interlaced or scanned fashion.

The monitoring device <NUM> using the light pipe inserts <NUM> according to the invention described herein exhibits the following advantages:.

The monitoring device <NUM> allows execution of a method for monitoring a semiconductor component for an automobile appliance under high current and/or by a monitoring device, said semiconductor element emitting photons when biased, by way of electroluminescence or photoluminescence, in an amount depending on temperature and/or current through the semiconductor component and/or its gate voltage, in particular including silicon carbide, said monitoring device being preferably formed according to any of the preceding claims, the method including:.

Claim 1:
A monitoring device (<NUM>) for a semiconductor component (<NUM>) for an automobile appliance under high current and/or voltage, said semiconductor component (<NUM>) having a light emitting surface (<NUM>) and emitting photons at the light emitting surface (<NUM>) when biased or reverse-biased, by way of electroluminescence or photoluminescence, in an amount depending on a temperature of and/or a current through the semiconductor component (<NUM>) and/or its gate voltage, wherein the semiconductor component (<NUM>) comprises particularly silicon carbide, the monitoring device (<NUM>) including a light pipe insert (<NUM>) having a light receiving end (<NUM>) and a light emitting end (<NUM>), the light pipe insert (<NUM>) being formed and placed to receive photoluminescence light or electroluminescence light from the semiconductor component (<NUM>) through a light receiving surface (<NUM>) formed at the light receiving end (<NUM>) to face at least part of the light emitting surface (<NUM>) of the semi-conductor component (<NUM>), and to conduct the received light to the light emitting end (<NUM>) for detecting the temperature of the semiconductor component (<NUM>) and/or a current through the semiconductor component (<NUM>) and/or a gate voltage of the semiconductor component (<NUM>) through an optical sensor (<NUM>) configured to be coupled to the light emitting end (<NUM>) of the light pipe insert (<NUM>), characterised in that the light pipe insert (<NUM>) comprises a light pipe body (<NUM>) having a foot section (<NUM>) at the light receiving end (<NUM>) and a shaft section (<NUM>) extending from the foot section (<NUM>) to the light emitting end (<NUM>), and wherein the light pipe body (<NUM>) is a solid monolithic body made of a transparent material such as a transparent polymer or a typical glass.