POWER ELECTRONIC COMPONENT INTEGRATING A THERMOELECTRIC SENSOR

Abstract

An electronic component may include a carrier, and a thermoelectric sensor and a power transistor which are arranged on the carrier. The power transistor may include a base layer containing a transistor material chosen from among gallium nitride, aluminium gallium nitride, gallium arsenide, indium gallium, indium gallium nitride, aluminium nitride, indium aluminium nitride, and mixtures thereof. The electronic component may be configured so that the thermoelectric sensor generates an electric current under the effect of heating from the power transistor.

Claims

1. An electronic component, comprising; a carrier; a thermoelectric sensor; and a power transistor, wherein the thermoelectric sensor and the power transistor are disposed on the carrier, wherein the power transistor comprises a base layer comprising a transistor material comprising gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, aluminum indium nitride, or a mixture thereof, wherein the electronic component is configured so that the thermoelectric sensor generates an electric current under the effect of heating from the power transistor.

2. The electronic component of claim 1, wherein the thermoelectric sensor is multilayered and comprises a base layer (25) comprising, for more than 99.9% of its mass, gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, aluminum indium nitride, or a mixture thereof, as a sensor material .

3. The electronic component of claim 2, wherein the base layer of the thermoelectric sensor is n-doped or p-doped by a doping element.

4. The electronic component of claim 3, wherein the base layer of the thermoelectric sensor comprises a blank portion devoid of the doping element, and a doped portion comprising the doping element.

5. The electronic component of claim 1 , wherein the thermoelectric sensor comprises a thermoelectric couple comprising a first thermoelectric member and a second thermoelectric member, wherein the first thermoelectric member comprises an n-doped or p-doped semiconductor material, and wherein the second thermoelectric member comprises a p-doped or n-doped semiconductor thermoelectric material, respectively, or of a thermoelectric metal.

6. The electronic component of claim 5, wherein the first thermoelectric member is formed by all or part of a layer of the thermoelectric sensor, which is n-doped or p-doped.

7. The electronic component of claim 2 5, wherein the thermoelectric sensor comprises an additional layer comprising a semiconductor material, wherein at least a portion of the semiconductor material of the additional layer is n-doped or p-doped, wherein the additional layer is stacked on, an upper face of the base layer of the thermoelectric sensor.

8. The electronic component of claim 5 , wherein the second thermoelectric member is at least partly housed in a groove provided in the base layer of the thermoelectric sensor and/or, if present, in an additional layer of the thermoelectric sensor.

9. The electronic component of claim 5 , wherein the thermoelectric sensor comprises an electrical insulation coating comprising an electrically insulating material, disposed between the first thermoelectric member and the second thermoelectric member.

10. The electronic component of claim 5 , wherein the first and second thermoelectric members are in contact in an electrical connection zone ,or are spaced apart from each other and electrically connected by an electrically conductive bridge.

11. An energy converter, a control unit of a motor, or a microwave power amplifier, comprising: the electronic component of claim 1.

12. A method for manufacturing an electronic component , comprising a power transistor and a thermoelectric sensor having first and second thermoelectric members, the method comprising : (a) depositing a first material onto a substrate to form a base layer of the power transistor and a base layer of the thermoelectric sensor, the first material comprising gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, aluminum indium nitride, or a mixture thereof; (b) n-type or p-type doping of at least one portion of the base layer of the thermoelectric sensor, or depositing a second material in contact with the base layer of the thermoelectric sensor in order to form an additional layer of the thermoelectric sensor, followed by n-type or p-type doping of at least one portion, of the additional layer of the thermoelectric sensor, the second material being different from the first material and comprising gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, aluminum indium nitride, or a mixture thereof; (c) forming at least one groove fully passing through the doped portion of the base layer of the thermoelectric sensor or fully passing through the doped portion of the additional layer of the thermoelectric sensor, with the doped portion of the base layer of the thermoelectric sensor or the additional layer of the thermoelectric sensor contiguous with the groove and extending along the groove defining the first thermoelectric member; (d) forming at least one electrical insulation coating covering all or part of the one or more faces of the groove; (e) forming at least one insertion layer at least partly in contact with the electrical insulation coating, and optionally p-type or n-type doping, respectively, the insertion layer, in order to form the second thermoelectric member.

13. The method of claim 12, wherein the doping (b) comprises n-type or p-type doping of at least one portion of the base layer of the thermoelectric sensor, and wherein the forming (c) comprises forming at least one groove fully passing through the doped portion of the base layer of the thermoelectric sensor, wherein the doped portion of the base layer of the thermoelectric sensor extends along the groove defining the first thermoelectric member.

14. The method of claim 12, wherein the doping (b) comprises depositing the second material in contact with the base layer of the thermoelectric sensor to form the additional layer of the thermoelectric sensor, followed by the n-type or p-type doping of the at least one portion of the additional layer of the thermoelectric sensor, wherein the second material differs from the first material and comprises gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, aluminum indium nitride, or a mixture thereof, and wherein the forming (c) comprises forming at least one groove fully passing through the doped portion of the additional layer of the thermoelectric sensor, wherein the doped portion of the additional layer of the thermoelectric sensor is contiguous with the groove and extending along the groove defining the first thermoelectric member.

15. The method of claim 14, comprising, in the doping (b), in conjunction with forming the additional layer of the thermoelectric sensor, depositing the second material onto the base layer of the transistor in order to form an additional layer of the transistor.

16. The method as claimed of claim 12 , further comprising: depositing a third material in the groove, wherein the third material is a thermoelectric metal, or a semiconductor material comprising gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, aluminum indium nitride, or a mixture thereof.

17. The method of claim 12, wherein the forming (d) is conducted so that the electrical insulation coating fully covers the one or more faces of the groove, and wherein the method further comprises forming an electrical connector electrically connecting the first and second thermoelectric members, in order to form a thermoelectric couple.

18. The method of claim 12 , comprising: forming a plurality of grooves in the forming (c), with two adjacent grooves being separated by a first adjacent thermoelectric member; forming a plurality of electrical insulation coatings each at least partially covering the one or more faces of one of the corresponding grooves; and forming and, optionally, doping, a plurality of insertion layers, each contained in one of the corresponding grooves, and wherein the optionally doped insertion layers define, with adjacent zones of the doped portion of the base layer of the thermoelectric sensor or of the doped portion of the additional layer of the electrical sensor, a plurality of thermoelectric couples .

19. The electronic component of claim 5, wherein the transistor material is at least one selected from the group consisting of gallium nitride, aluminum gallium nitride, gallium arsenide, gallium indium, gallium indium nitride, aluminum nitride, and aluminum indium nitride.

Description

[0192] The invention can be better understood from reading the following detailed description and the examples and by means of the appended drawings, in which:

[0193] FIG. 1FIG. 1 illustrates, as a cross section view, a step of the method according to a first embodiment;

[0194] FIG. 2FIG. 2 illustrates, as a cross section view, another step of the method according to the first embodiment;

[0195] FIG. 3FIG. 3 illustrates, as a cross section view, another step of the method according to the first embodiment;

[0196] FIG. 4aFIG. 4a illustrates, as a cross section view, another step of the method according to the first embodiment;

[0197] FIG. 4bFIG. 4b illustrates, as a top view, the step of the method illustrated in FIG. 4a;

[0198] FIG. 5aFIG. 5a illustrates, as a cross section view, another step of the method according to the first embodiment;

[0199] FIG. 5bFIG. 5b illustrates, as a top view, the step of the method illustrated in FIG. 5a;

[0200] FIG. 6 FIG. 6 illustrates, as a cross section view, another step of the method according to the first embodiment;

[0201] FIG. 7aFIG. 7a illustrates, as a cross section view, another step of the method according to the first embodiment;

[0202] FIG. 7bFIG. 7b illustrates, as a top view, the step of the method illustrated in FIG. 7a;

[0203] FIG. 8FIG. 8 illustrates, as a cross section view, another step of the method according to the first embodiment;

[0204] FIG. 9aFIG. 9a illustrates, as a cross section view, another step of the method according to the first embodiment;

[0205] FIG. 9bFIG. 9b illustrates, as a top view, the step of the method illustrated in FIG. 9a;

[0206] FIG. 10FIG. 10 illustrates, as a cross section view, another step of the method according to the first embodiment;

[0207] FIG. 11aFIG. 11a illustrates, as a cross section view, another step of the method according to the first embodiment;

[0208] FIG. 11bFIG. 11b illustrates, as a top view, the step of the method illustrated in FIG. 11a;

[0209] FIG. 12aFIG. 12a illustrates, as a cross section view along the cutting plane (II), another step of the method according to the first embodiment;

[0210] FIG. 12bFIG. 12b illustrates, as a top view, the step of the method illustrated in FIG. 12a;

[0211] FIG. 13aFIG. 13a illustrates, as a cross section view, another step of the method according to the first embodiment;

[0212] FIG. 13bFIG. 13b illustrates, as a top view, the step of the method illustrated in FIG. 13a;

[0213] FIG. 14FIG. 14 illustrates, as a cross section view, an electronic component according to the invention manufactured according to the first embodiment;

[0214] FIG. 15FIG. 15 illustrates, as a top view, a step of the method according to a second embodiment;

[0215] FIG. 16FIG. 16 illustrates, as a cross section view along the cutting plane (AA), the step of the method illustrated in FIG. 15;

[0216] FIG. 17FIG. 17 illustrates, as a cross section view along the cutting plane (CC), the step of the method illustrated in FIG. 15;

[0217] FIG. 18FIG. 18 illustrates, as a cross section view, a step of the method according to a third embodiment;

[0218] FIG. 19 illustrates, as a cross section view, an electronic component according to the invention manufactured according to the third embodiment; and

[0219] FIG. 20FIG. 20 is a schematic top view of another example of an electronic component according to the invention.

[0220] For the sake of the clarity of the drawings, the proportions of the various constituent elements of the illustrated electronic components are not shown to scale.

Example 1

[0221] FIGS. 1 to 14 show a first embodiment of the method according to the invention for manufacturing an example of an electronic component according to the invention.

[0222] In step a), as illustrated in FIG. 1, a substrate 5 is provided that comprises a carrier 10 made of silicon and a primary layer 15 made of aluminum nitride, which covers the substrate. For example, the thickness e.sub.s of the carrier is equal to 1.0 mm and the thickness e.sub.p of the primary layer of aluminum nitride is equal to 50 nm.

[0223] In step b), gallium nitride is deposited, for example, by physical vapor deposition or by chemical vapor deposition, in contact with the primary layer of aluminum nitride. An initial layer is thus formed. The initial layer then can be separated into two separate parts, for example, using lithography and etching, in order to form a base layer 20 of the power transistor and a base layer 25 of the thermoelectric sensor, as illustrated in FIG. 2. The base layer of the power transistor and the base layer of the thermoelectric sensor are separated by a separation distance d, which is selected so that the thermoelectric sensor generates an electric voltage under the effect of heating from the transistor. The separation distance d ranges, for example, between 1 .Math.m and 1,000 .Math.m. Furthermore, the respective lower faces 30, 35 of the base layers 20 and 25 can be disposed at the same height H of the upper face 40 of the carrier.

[0224] According to an alternative embodiment, as illustrated in FIG. 3, the base layer 25 of the multilayer sensor is doped in step b), for example, by ion implantation. A doping element, for example, silicon, is introduced via the upper face of the base layer 25, and diffuses into a doped portion 45 directly under the upper face 50 of the base layer 25. Thus, the layer is n-doped. For example, the doped portion 45 extends over a thickness p.sub.ss under the upper face that is equal to 25 nm. In FIG. 3, the dashed line represents the boundary between the blank portion 55 of the base layer 25, in which the base layer is substantially devoid of the doping element, and the doped portion 45, in which more than 99% of the doping element is concentrated.

[0225] In step c), grooves are formed on the upper face of the base layer of the thermoelectric sensor. As illustrated in FIGS. 4a and 4b, a mask 65 is formed on the upper face 70 of the base layer 25 of the thermoelectric sensor using photolithography. It comprises at least one solid portion 75, made up of, for example, a heat-sensitive resin, and recesses 80a-b stacked on portions 85a-b of the upper face of the base layer where the grooves are intended to be formed.

[0226] The base layer of the thermoelectric sensor is then etched into the portions 85a-b not covered by the solid portions of the mask. The mask is then removed by stripping. As illustrated in FIGS. 5a and 5b, grooves 90a-b are thus formed, the respective depths p.sub.r of which are greater than the thickness p.sub.ss of the doped portion 45. The grooves each assume the form of a strip, viewed in a direction n normal to the carrier, which extends over the entire length of the base layer of the thermoelectric sensor between two of its edges 95, 100 that are opposite one another.

[0227] Thus, first thermoelectric members 105a-c of thermoelectric couples in formation are created, which respectively comprise parts 45a, 45b and 45c of the doped portion 45.

[0228] They each assume, viewed in a direction normal to the carrier, the form of a strip, and extend parallel to the adjacent grooves.

[0229] The first thermoelectric members 105a-c are thus spaced apart and electrically insulated from each other, with the grooves having depths p.sub.r that are greater than the thickness p.sub.ss of the doped portion 45, and extending on either side between the edges 95 and 100.

[0230] In the illustrated example, each groove has a length L.sub.r of 1.0 mm, a width l.sub.r of 2.06 .Math.m and a depth p.sub.r of approximately 125 nm, and each of the first thermoelectric members has a length L.sub.1th of 1.0 mm, identical to the length of a groove, a width 1.sub.1th of 4.0 .Math.m and a thickness, corresponding to the thickness of the doped portion 45, that is equal to 25 nm.

[0231] In step d), an electrical insulation coating is formed. An electrically insulating material can be deposited, as illustrated in FIG. 6, onto the upper face 70 of the base layer 25 of the thermoelectric sensor, and onto the respective bottom faces 115a-b of the grooves. A temporary layer 110 is thus formed. The electrically insulating material is, for example, alumina and can be deposited using CVD, ALD or PECVD.

[0232] A mask 120 is then generated using photolithography, with the solid portions 125 of the mask being fully stacked on the groove, as illustrated in FIGS. 7a and 7b. The temporary layer is then etched in the one or more parts thereof not covered by the solid portions of the mask, as illustrated in FIG. 8. After stripping the solid portions of the mask, electrical insulation coatings 130a-b are formed, each entirely covering the side faces 135a-b, 140a-b and the bottom face 145a-b of each of the grooves. Thus, each electrical insulation coating extends along the entire width and over the entire length of the groove that it covers.

[0233] In step e), in the illustrated example, a third material, for example, a thermoelectric metal, in particular aluminum, is deposited onto the upper face of the base layer of the thermoelectric sensor and onto the electrical insulation coating, so as to form another temporary layer 150. Another mask 155 is then formed using photolithography, the solid portions 160a-b of which fully cover the groove, as illustrated in FIG. 10.

[0234] After etching the other temporary layer and stripping the other mask, insertion layers 170a-b are formed that each completely fill a corresponding groove. Each insertion layer projects from the upper face of the base layer of the thermoelectric sensor. Furthermore, with the insertion layers being formed by a thermoelectric material, they each define the second thermoelectric members 175a-b intended to form, with corresponding first thermoelectric members, thermoelectric couples.

[0235] Each second thermoelectric member is thus contiguous with a first thermoelectric member. The electrical insulation coating forms a barrier between a first thermoelectric member and a second adjacent thermoelectric member, which are thus electrically insulated from each other, as illustrated in FIGS. 11a and 11b.

[0236] Furthermore, when viewed in the direction n normal to the carrier, the first and second thermoelectric members each extend in extension directions D.sub.E parallel to each other, and are alternately aligned side by side in an alignment direction D.sub.A perpendicular to the extension direction D.sub.E. Two adjacent first and second thermoelectric members thus form a pattern that is regularly repeated in the alignment direction D.sub.A.

[0237] In an alternative embodiment, not illustrated, the third material can be a semiconductor and the method can comprise doping the insertion layer in order to impart thermoelectric properties thereto. In the illustrated example, the base layer 25 is made of n-doped gallium nitride, the third material can be gallium nitride or aluminum gallium nitride, and the insertion layer can be p-doped by implanting beryllium, magnesium, zinc or carbon.

[0238] As described above, in the illustrated example, at the end of step e), the first thermoelectric members are electrically insulated from the second thermoelectric members by means of the electrical insulation coating. In order to form thermoelectric couples capable of generating a Seebeck effect, the method implemented in example 1comprises depositing a first silica layer 180, which covers both the parts 185a-b, 190a-b of the longitudinal ends of the first thermoelectric members and the second thermoelectric members, respectively. As illustrated in FIGS. 12a and 12b, the first silica layer extends on either side of the base layer of the thermoelectric sensor and on the insertion layers, in the alignment direction D.sub.A. When viewed in the direction normal to the carrier, the silica layer thus assumes the form of a rectilinear strip, the width 1.sub.b of which is, for example, equal to 5.5 .Math.m. Furthermore, the first silica layer comprises first 195a-b and second 200a-b openings passing through the thickness thereof and which open into the upper face 205a-b of the first thermoelectric member and into the upper face 210a-b of the second thermoelectric member, respectively. Furthermore, the method comprises forming first 215a-b and second 220a-b electrically conductive pads, for example, made of metal, and in particular made of aluminum, which are housed in the openings. The openings, as well as the electrically conductive pads, can be successively formed using a lithography and etching technique as described elsewhere in this description.

[0239] Finally, the method implemented in example 1 comprises, as illustrated in FIGS. 13a and 13b, forming a second silica layer 240, which is fully stacked on the first silica layer 180, and vice versa. The second layer comprises another opening 245a-b, which fully passes through the thickness thereof and which opens into the first 220a-b and second 225a-b electrically conductive pads. The other opening is also stacked on the first silica layer and on a first thermoelectric member and on a second adjacent thermoelectric member. An electrically conductive strip 250a-b, for example, made of aluminum, is housed in the opening and is in contact with the first and second electrically conductive pads. Thus, the pads and the electrically conductive strip define an electrically conductive bridge 260a-b that connects adjacent first 105a-b and second 170a-b thermoelectric members. Furthermore, the portion of the first silica layer sandwiched between the electrically conductive bridge and the thermoelectric members is an electrically insulating spacer 270a-b.

[0240] The first and second thermoelectric members are thus electrically connected in an electrical connection zone 280 extending over the longitudinal end portion over a length that is less than the width 1.sub.b of the silica strip, and are electrically insulated from each other over an electrical insulation zone 290 that extends over the length of the groove. Thermoelectric couples 300a-b are thus created, which each comprise first 105a-b and second 170a-b thermoelectric members connected by the electrically conductive bridge 260a-b, respectively, which under the effect of heating from the transistor is capable of generating an electric current by the Seebeck effect.

[0241] In order to increase the voltage generated by the sensor, the thermoelectric couples can be interconnected in series with one another. In conjunction with the formation of the first silica layer 180, the method comprises forming another silica layer 310, which covers the longitudinal end parts 320a-b, 330a-b of the first thermoelectric members and the second thermoelectric members, respectively, opposite the first silica layer 180. Interconnection members 340a-b connecting the second thermoelectric member, for example, 170a, of a thermoelectric couple, for example, 300a, to the first thermoelectric member, for example, 105b, of an adjacent thermoelectric couple, for example, 105b, are formed, according to a method identical to that described above for generating the electrically conductive bridges.

[0242] A thermoelectric sensor 350, formed by thermoelectric couples electrically connected in series, is thus obtained by means of the method implemented in example 1.

[0243] It can be connected to a voltmeter or an ammeter, by means of connection pastes 352a-b deposited onto the carrier and to which it is connected, for measuring the electric voltage or the electric current respectively generated by the power transistor 355 disposed nearby on the carrier, as illustrated in FIG. 14.

[0244] Furthermore, the method can comprise forming one or more layers stacked on the base layer of the transistor in order to form the power transistor 355.

[0245] For example, the method comprises forming an additional layer 356 of the transistor, for example, formed by aluminum gallium nitride, in contact with the base layer 20 of the gallium nitride transistor. The additional layer of the transistor is, for example, n-doped in the illustrated example. It can be formed by a step following the step of depositing the base layers of the transistor and of the thermoelectric sensor. The method further comprises forming a drain layer 357 and a source layer 358, which are metal and which, for example, are partly formed during the operation of depositing the third material of the insertion layer of the thermoelectric sensor. An insulation layer 359 of the transistor and a gate layer 360 finally can be formed on the additional layer. An electronic component 365 comprising an HEMT-type power transistor 355 is thus obtained that is disposed on the carrier near the thermoelectric sensor 350.

[0246] The electronic component 365 illustrated in FIG. 20 differs from that illustrated in FIG. 14 by disposing the transistor 355 relative to the thermoelectric sensor 350. A face 450 of the transistor is disposed facing a face 455 of the thermoelectric sensor, which is substantially perpendicular to the extension directions of the first 105a-b and second 170a-b thermoelectric members. Such a relative disposition of the transistor relative to the thermoelectric sensor optimizes the generation of an electric current by the thermoelectric sensor when the transistor is heated. The accuracy of the measurement of the increase in temperature of the transistor thus can be improved.

Example 2

[0247] The thermoelectric sensor of the electronic component of example 2, according to the invention, differs from that illustrated in example 1in that the first and second thermoelectric members of a thermoelectric couple are in direct contact with each other in an electrical connection zone 370.

[0248] The thermoelectric sensor can be manufactured by implementing steps a) to c) described above in order to form a groove in the doped base layer of the thermoelectric sensor.

[0249] As illustrated in FIG. 15, the manufacturing method differs from that implemented in example 1in that an electrical insulation coating 130a-b is formed that partially covers only the faces of the groove. In order to form such a coating, a mask is deposited onto the temporary layer 110, which is not stacked on a portion of the groove in a longitudinal end portion 370a-b of the groove. In particular, in said longitudinal end portion, the electrical insulation coating 130a covers the part of the groove contiguous with a doped portion 45.sub.2 of the base layer of the thermoelectric sensor intended to form a first thermoelectric member 105b of another adjacent thermoelectric couple. Thus, the formation of a short circuit within the thermoelectric sensor is prevented.

[0250] The method then comprises forming an insertion layer as described in example 1, which fills the entire volume of the groove. As illustrated in FIG. 16, the second thermoelectric member 170a-b thus formed is, in the end portion of the groove, in direct contact with a first adjacent thermoelectric member in an electrical connection zone 375a-b and is electrically insulated from the other adjacent first thermoelectric member. The electrical contact zone can particularly extend, over a distance L.sub.z measured along the length of the groove, by less than 10 .Math.m. Furthermore, in the electrical insulation zone 380a-b, where the electrical insulation coating entirely covers the faces of the groove, the first and second thermoelectric members are spaced apart from each other and are electrically insulated, as illustrated in FIG. 11a.

[0251] The method according to the second example is thus particularly simple to implement. The thermoelectric sensor can be manufactured with a limited number of layers to be deposited.

[0252] Furthermore, in order to interconnect two adjacent thermoelectric couples, the electrical insulation coating is not stacked, in the opposite end portion 390a-b of the groove, on the face of the groove 140a-b contiguous with the doped portion of the base layer of the thermoelectric sensor intended to form a first thermoelectric member of another thermoelectric couple. Thus, in the electrical interconnection zone as illustrated in FIG. 17, the second thermoelectric member 170a of a thermoelectric couple 300a is in direct contact with the first thermoelectric member 105b of the adjacent thermoelectric couple 300b. The adjacent thermoelectric couples are thus connected in series.

Example 3

[0253] The manufacturing method according to the invention implemented in example 3 differs from that implemented in example 1 in that in step b) it comprises depositing a second contact material of the base layer of the thermoelectric sensor in order to form an additional layer 385 of the thermoelectric sensor.

[0254] Preferably, the second material is simultaneously deposited, in step b), onto the base layer of the transistor in order to form an additional layer of the transistor 356. Thus, the thermoelectric sensor 350 and the power transistor can respectively comprise a multilayered stack of sensors 390 and a multilayered stack of transistors 400 arranged on the carrier 10 and formed by a succession of layers comprising the same materials.

[0255] In the example illustrated in FIGS. 18 and 19, the multilayered stack of sensors and the multilayered stack of transistors comprise the same succession of layers formed by: [0256] a primary layer 15 made of aluminum nitride; [0257] a base layer 20, 25 made of non-doped gallium nitride; and [0258] an additional layer 356, 385 made of aluminum gallium nitride.

[0259] Furthermore, the method comprises doping the additional layer of the sensor, and optionally the additional layer of the transistor. In the illustrated example, at the end of step b), the additional layer of the thermoelectric sensor is made of n-doped aluminum gallium nitride over its entire thickness. As an alternative embodiment, it can be doped on only one portion, which, for example, extends directly under the upper face 386 of the additional layer of the thermoelectric sensor.

[0260] In step c), grooves are formed in accordance with a lithography and etching technique as described in example 1, with the method being conducted such that the depth p.sub.r of the groove is greater than or equal to the thickness e.sub.a of the additional doped layer, with the bottom of each groove being defined by a face of the base layer of the thermoelectric sensor made of non-doped gallium nitride. Thus, first thermoelectric members 105a-c, formed by n-doped gallium aluminum nitride are formed, which are electrically insulated from each other by the base layer of the thermoelectric sensor.

[0261] The other steps for forming the second thermoelectric members, then for connecting between the first and second thermoelectric members in order to create thermoelectric couples, and finally for connecting the thermoelectric couples in series, are identical to those described in example 1.

[0262] As an alternative embodiment, the transistor of the electronic component of FIG. 19 can be disposed relative to the thermoelectric sensor, as illustrated in FIG. 20.

Example 4

[0263] The manufacturing method of example 4, not illustrated, differs from that described in example 3, in that it comprises a step of forming the electrical insulation coating as described in example 2. Thus, the second thermoelectric member is in contact with the first thermoelectric member made of doped aluminum gallium nitride in the electrical connection zone.

[0264] Of course, the invention is not limited to the examples and embodiments of the electronic component and to the embodiments of the method described in the application. For example, the thermoelectric sensor can be formed on another carrier, then transferred onto the carrier on which the power transistor rests.