DE102006046844A1 - Semiconductor component e.g. thyristor, has n conductor type field top zone provided with higher net-doping material concentration than section of another n conductor type semiconductor zone - Google Patents

Abstract

The semiconductor component has a p conductor type semiconductor zone (10), a n conductor type semiconductor zone (20) and a p conductor type semiconductor zone (30) arranged one after another between a front side (11) and a back side (12) of a semiconductor body. The zone (20) includes a n conductor type field top zone (21) arranged distant from the zone (10). A net-doping material concentration of the zone (21) is higher than a section (23) of the zone (20), where the section (23) is arranged between the zone (10) and the zone (21). An independent claim is also included for a method for producing a semiconductor component.

Description

The The invention relates to a power semiconductor device with field stop zone and a method for its production.

In The power electronics there are a variety of applications, for example Inverter topologies in the form of matrix converters, the circuit breakers require which in both directions lock high voltages and the one with suitable control in one direction or in both directions Carry electricity can.

Lots Power semiconductor switches are only blocking in one direction, while they are either conducting in the other direction (eg MOSFETs) or only a reduced blocking ability have (eg IGBTs), which is significantly lower than the blocking ability in Forward direction. The cause of this can in the vertical structure of such devices as well as in the Construction of the edge termination lie.

to Realization of the reverse blocking capability With such a device two possibilities are known.

A first possibility is based on power semiconductor switches with a vertically asymmetric doping profile, which are connected in series with a diode. In order to optimize the forward blocking capability, such circuit breakers usually have a heavily doped field stop zone, as in the example of the course 81 the net dopant concentration of a prior art power semiconductor switch between a front side 11 and a back 12 in a vertical direction v of the device in 17 is shown.

The device has a heavily n-doped field stop zone 21 immediately adjacent to a heavily p-doped zone at the back 12 of the component adjacent. Furthermore, in 17 the history 82 the amount of the electric field E shown in the forward direction of the component voltage.

to increase the reverse blocking capability Such circuit breakers usually connected in series with a diode. The disadvantage here, however, that in the case of transmission at least twice a diode voltage of 0.5 V to 0.7 V at the series connection drops.

A second possibility is to form the semiconductor component as an NPT component (NPT = non-punch-through). Such NPT devices have a substantially symmetrical doping profile with a low dopant concentration in the vertical direction, as shown by way of example in FIG 18 is shown. 18 also shows the course of the amounts of the electric field E with voltage applied in the forward direction (curve 82 ) as well as in the reverse direction voltage (curve 83 ).

the Advantage of only simple diode threshold in such a NPT device however, in the case of passage there is the disadvantage that NPT components are thicker Semiconductor chips require, thereby reducing both the forward voltage as well as the switching losses increase. The chip thicknesses for an NPT device are typically larger by a factor of 1.5 than a corresponding device with field stop zone.

From the WO 00/35021 A1 For example, an IGBT is known having two spaced apart field stop zones, one on the front and the other on the back immediately adjacent to a p-doped region and produced by diffusion processes. The disadvantages of this IGBT are that such field stop zones can not be made buried by diffusion and that the neutral zone, ie the zone without space charge, has only a very small extent.

The The object of the present invention is a semiconductor component and a method for producing a semiconductor device with improved reverse blocking capability in which the competing sizes are forward voltage, storage charge and surge current resistance in an optimized ratio to stand by each other.

These The object is achieved by a semiconductor device according to claim 1 and by a method for producing such a semiconductor device according to the claims 35 and 37 solved. Preferred embodiments The invention are the subject of subclaims.

The inventive semiconductor device has a semiconductor body on, in between a front and one of the front opposite back in a vertical direction, a first semiconductor zone of one first conductivity type, a second semiconductor region from one to the first Complementary line type second conductivity type and a third semiconductor region of the first conductivity type are arranged consecutively.

The second semiconductor zone has a first field stop zone of the second conductivity type spaced from the first semiconductor zone and having a higher net dopant concentration than the portion of the first semiconductor zone located between the first semiconductor zone and the first field stop zone second semiconductor zone.

It also includes the second semiconductor zone a field stop zone also from the second Conductivity type spaced from the third semiconductor zone and the one higher Has net dopant concentration than that between the third semiconductor zone and the second field stop zone arranged portion of the second Semiconductor zone.

In this case, the doping dose of the first field stop zone and / or the doping dose of the second field stop zone is from 0.25 to 0.75 times, preferably about 0.5 times, the so-called breakdown doping dose. This is doping-dependent and is typically between 1.3 × 10 ¹² cm ^-2 and 2 × 10 ¹² cm ^-2 in silicon ^devices .

Of the Distance of the first field stop zone from the front and / or the The distance of the second field stop zone from the backside is typically 10% to 30% of the thickness of the second semiconductor zone. In extreme cases may be one of the field stop zones just below the pn junction where also an asymmetrical arrangement of the field stop zones in Semiconductor body chosen can be.

The Thickness of the first and second field stop zones in the vertical direction should be as low as possible chosen and preferably less than 5% of the thickness of the second semiconductor layer be. In a further preferred embodiment, the thickness is these field stop zones less than 5 microns.

Farther it is advantageous to measure the thicknesses measured in the vertical direction between the first and the second field stop zone, between the first field stop zone and the first semiconductor zone and the between the second field stop zone and the third semiconductor zone Select sections of the second semiconductor zone as low as possible.

The Aim of this measure is the vertical distribution of the electric field in the semiconductor device to be set so that on the one hand the local Integral of the field strength over the Space charge zone in the vertical direction of the device, i. the voltage drop over the space charge zone in the vertical direction, is significantly higher and on the other hand, the resulting at full reverse voltage vertical Extension of the neutral zone is significantly larger than a corresponding one conventional semiconductor device.

According to one preferred embodiment of Invention is the dimension of the between the first semiconductor zone and the first field stop zone arranged portion of the second Semiconductor zone in the vertical direction greater than or equal to the dimension between the third semiconductor zone and the second field stop zone arranged portion of the second semiconductor region in the vertical direction.

The section of the second semiconductor zone arranged between the first semiconductor zone and the first field stop zone and / or the section of the second semiconductor zone arranged between the third semiconductor zone and the second field stop zone and / or the section of the second semiconductor zone arranged between the first field stop zone and the second field stop zone are preferred a net dopant concentration of less than or equal to 1 × 10 ¹⁴ cm ^-3 , more preferably less than or equal to 1 × 10 ¹³ cm ^-3 .

In addition, show between the first semiconductor zone and the first field stop zone arranged portion of the second semiconductor zone and / or between the third semiconductor zone and the second field stop zone arranged Section of the second semiconductor zone and / or between the first Field stop zone and the second field stop zone arranged section the second semiconductor region preferably a dopant dose of smaller or equal to 25% of the breakthrough doping dose.

The Net dopant concentration of the between the first semiconductor zone and the first field stop zone arranged from section of the second semiconductor zone can be the same, bigger or smaller than the net dopant concentration of between the third Semiconductor zone and the second field stop zone arranged portion the second semiconductor zone selected become.

the preparation, each of the first and second field stop zones has a location or an area on, at or in which the relevant field stop zone has a maximum net dopant concentration. It is the vertical distance of the point of maximum net dopant concentration the first field stop zone from the front preferably larger or equal to the vertical distance of the point of maximum net dopant concentration the second field stop zone from the back of the semiconductor body.

Such a field stop zone preferably extends at least in certain sections of the semiconductor component as a substantially planar layer and may be formed, for example, as a continuous layer, strip-like, reticulated or island-like, said embodiments of different field stop zones of the same semiconductor device independently selected and can be combined with each other as desired. Although a structured embodiment of the field stop zone requires a higher production outlay, however, the component then has an improved switch-on behavior.

The first and second field stop zones are generally different from each other spaced. Alternatively, you can however, the first field stop zone and the second field stop zone immediately adjoin one another or be identical.

The first semiconductor zone may extend to the front of the semiconductor body and / or extend the third semiconductor zone to the back of the semiconductor body. Likewise depending but one or both of these semiconductor zones from the front and / or from the back be spaced.

The Production of the first and / or second field stop zones or optional one or more further field stop zones of a semiconductor device according to the invention can, for example, by means of a masked implantation of protons and a subsequent annealing annealing step.

Between the front side of the semiconductor body and the first field stop zone and / or between the back side of the semiconductor body and the second field stop zone for the realization of a specific semiconductor device, for example a thyristor, an IGBT, a MOSFET, etc., further layers, in particular doped semiconductor layers may be provided.

The first field stop zone and / or between the first field stop zone and the front-facing portion of the second semiconductor zone and / or the first semiconductor zone and / or an optionally existing, between the third semiconductor zone and the front Section of the semiconductor body can for producing a cell structure, for example the cell structure of an IGBT or a thyristor.

is the semiconductor device formed as a thyristor, so make the first semiconductor zone and the second semiconductor zone preferably the base zones and the third semiconductor zone and a fourth semiconductor zone Preferably, the emitter regions of the thyristor.

Farther For example, the first conductivity type may be p-type and the second conductivity type be n-conductive. Conversely, however, the first conductivity type can also be used n-type and the second conductivity type g-type.

The Invention will be described below with reference to preferred embodiments with reference to figures closer explained. In the figures show:

1 FIG. 2 shows a vertical section through a section of a thyristor whose n-base has two spaced-apart field stop zones which are each at a distance from both the p-base and the p-emitter. FIG.

2 the vertical profile of the net dopant concentration of the thyristor according to 1 .

3 the current-voltage characteristic of the thyristor according to 1 up to a maximum reverse current of 100 mA compared to the current-voltage characteristic of a conventional thyristor structure without field stop zone, also up to a maximum reverse current of 100 mA,

4 the course of the electric field strength of the thyristor according to 1 with a reverse current of 100 mA compared to the course of the electric field strength of a conventional thyristor without field stop zone, also with a reverse current of 100 mA,

5 the dependence of the blocking voltage of a thyristor with double-sided field stop zone of the field stop dose for two different basic dopings of the semiconductor body compared to the blocking voltage of a thyristor without field stop zone,

6 the course of the net dopant concentration of a field stop zone produced after a hydrogen implantation followed by an annealing step,

7 the course of the net dopant concentration and the electric field strength with applied forward or reverse voltage of a semiconductor device according to the invention with two spaced field stop zones and symmetrical doping profile,

8th the course of the net dopant concentration and the electric field strength with applied forward or reverse voltage of a semiconductor device according to the invention with two spaced field stop zones, wherein a arranged between a first field stop zone and the front of the semiconductor body portion of the second semiconductor zone has a higher net dopant concentration than between the second field stop zone and the rear side arranged portion of the second semiconductor zone,

9 the course of the net dopant concentration and the electric field strength with applied forward and reverse voltage according to a semiconductor device according to 8th in which the portion of the second. between the first field stop zone and the second field stop zone Semiconductor zone has a net dopant concentration that is higher than the net dopant concentration of both the between the first field stop zone and the front and between the second field stop zone and the back disposed portion of the second semiconductor zone,

10 the course of the net dopant concentration and the electric field strength with applied forward and reverse voltage according to 7 in which the first field stop zone and the second field stop zone are identical,

11 the course of the net dopant concentration and the electric field strength with applied forward and reverse voltage according to a semiconductor device according to 8th in which the first field stop zone and the second field stop zone are identical,

12 a cross-section through a portion of a semiconductor device having two spaced apart field stop zones, each formed of spaced-apart and substantially in-plane islands,

13 a cross section through the arrangement according to 12 in vertical planes AA 'and BB' in the area of the first field stop zone,

14 4 a vertical section through a section of an IGBT with two field stop zones, of which the first field stop zone and also the section of the semiconductor body arranged between the first field stop zone and the front side are structured to form an IGBT cell,

15 a cross section through an IGBT according to 14 , with the difference that the first field stop zone is not structured,

16a C various steps of a wafer bonding method for producing a semiconductor device with two field stop zones,

17 the asymmetrical course of the net dopant concentration and the electric field strength with applied forward voltage of a semiconductor device with a field stop zone according to the prior art, and

18 the course of the net dopant concentration and the electric field strength with applied forward or reverse voltage of a semiconductor device with NPT structure according to the prior art.

In the characters became reasons the clarity on a scale Presentation omitted. Unless otherwise indicated show the same Reference numerals like parts with the same function.

1 shows a vertical section through a portion of a thyristor with a semiconductor body 1 , Between a front side 11 and one of these opposite backs 12 of the semiconductor body 1 are consecutively a first semiconductor zone in a vertical direction v 10 , a second semiconductor zone 20 and a third semiconductor zone 30 arranged. Between the first semiconductor zone 10 and the front 11 is an optional fourth semiconductor zone 40 intended. The first semiconductor zone 10 and the third semiconductor zone 30 have a p-type dopant concentration, the second semiconductor zone 20 and the fourth semiconductor zone 40 an n-net dopant concentration.

The net doping dose of the first field stop zone 21 and / or the second field stop zone 22 is preferably in each case 0.25 times to 0.75 times, particularly preferably in each case 0.4 to 0.6 times the breakthrough doping dose.

The second semiconductor zone 20 includes a first sub-zone 21 , a second subzone 22 , a third sub-zone 23 , a fourth sub-zone 24 and a fifth sub-zone 25 , The first subzone 21 is subsequently referred to as the first field stop zone, the second sub-zone 22 referred to as second field stop zone. All subzones 21 to 24 are of the same conductivity type, with the first field stop zone having a higher net dopant concentration than any of the sub-zones immediately adjacent to it 23 and 25 , Accordingly, the second field stop zone 22 a higher net dopant concentration than the respective immediately adjacent subzones 24 and 25 ,

According to a preferred embodiment of the invention, that between the first semiconductor zone 10 and the first field stop zone 21 arranged section 23 the second semiconductor zone 20 and between the third semiconductor zone 30 and the second field stop zone 22 arranged section 24 the second semiconductor zone 20 in the vertical direction v identical dimensions d23 and d24, respectively.

The first field stop zone 21 has a location S1 at which its net dopant concentration reaches a maximum and that in the vertical direction v reaches a distance t1 from the front 11 has. Accordingly, the second field stop zone 22 a point S2 in which their net dopant concentration takes a maximum value and a distance t2 from the back side 12 having. The maximum values of the dopant concentrations of the first and second field stop zones 21 respectively. 22 beforehand preferably not only at a point S1 or S2, but at several points or at all points reached, which are each arranged in a plane parallel to the back.

The distance t1 of the point S1 of the maximum net dopant concentration of the first field stop zone and / or the distance t2 of the point S2 of the maximum net dopant concentration of the second field stop zone from the back 12 is preferably in each case the sum of the distance of the pn junction between the first semiconductor zone 10 and the second semiconductor zone 20 from the front side and the double thickness of the neutral zone of a conventional thyristor without field stop zone designed for the same forward blocking capability.

The distances t1 and t2 are chosen equal in the present case. Since the breakdown voltage of a thyristor is generally significantly lower than the blocking voltage, the depth t2 of the anode-side field stop zone 22 are also chosen to be slightly lower than the depth t1 of the cathode-side field stop zone 21 so that the device thickness can be further reduced and the blocking capability approaches each other in both poling directions. Likewise, the donor dose in the two field stop zones can be chosen differently to account for this effect. In principle, however, it is also possible to use the depth t2 of the anode-side field stop zone 22 greater than the depth t1 of the cathode-side field stop zone 21 ,

The achievable with a thyristor according to the invention increase of blocking and tilting voltage can be used in particular to at a given locking and tilting voltage, the thickness t1 + t2 + t3 of the thyristor opposite the thickness of a conventional one To reduce thyristors.

The The aim of this arrangement is to control the vertical distribution of the electric field so that on the one hand the integral this field strength distribution along the vertical coordinate is significantly higher and on the other hand the vertical expansion of the neutral at full blocking voltage Zone is significantly larger than the conventional thyristor.

The thicknesses d1 of the first field stop zone 21 and d2 of the second field stop zone 22 should be chosen small compared to the thickness d20 of the second semiconductor zone 20 , The thickness d1 of the first field stop zone 21 and / or the thickness d2 of the second field stop zone 22 is preferably less than 5% of the thickness d20 of the second semiconductor zone 20 ,

A possible course 81 the net dopant concentration N of the thyristor according to 1 is in 2 shown in logarithmic representation.

3 shows the (continuous) current-voltage characteristic 91 a thyristor according to the invention according to 1 in comparison to the (dashed) current-voltage characteristic 90 a conventional thyristor without field stop zone with the same blocking capability.

Of the Comparison clearly shows that the thyristor according to the invention almost over the entire reverse voltage range has a lower reverse current as a conventional thyristor.

The course of the amounts of electric field strengths of these thyristors with the (continuous) characteristic 93 for the thyristor according to the invention and the (dashed) characteristic 92 for the conventional thyristor in each case compared with a reverse current of 100 mA compared.

While the magnitude of the electric field in the second semiconductor region of the conventional thyristor increases linearly, the magnitude of the electric field in the second semiconductor region of a thyristor according to the invention shows a stepwise progression, wherein the locations of the stepwise increase of the magnitude of the electric field strength respectively at the location of the first and second field stop zone 21 . 25 at one of the front 11 measured depth of about 0.5 mm and 0.97 mm, respectively.

5 shows the dependence of the reverse voltage of two inventive thyristors according to 1 from the net doping dose of the two field stop zones 21 . 22 compared to the blocking voltage of a conventional thyristor, each at a temperature of 363 K.

The dashed course 96 corresponds to a thyristor according to the invention, whose third, fourth and fifth sub-zone 23 . 24 respectively. 25 a net dopant concentration of 8.15 x 10 ¹¹ cm ^-3 , the solid line 97 the second thyristor according to the invention, the third, fourth and fifth sub-zone 23 . 24 respectively. 25 have a net dopant concentration of 5.0 × 10 ¹⁰ cm ^-3 , each with a reverse current of 100 mA. According to a preferred embodiment of the invention, the donor dose is in the first and second field stop zones 21 respectively. 22 chosen identically.

Since the processing of a thyristor usually takes place starting from a substrate having a basic doping, the net dopant concentration corresponds to the third, fourth and fifth sub-zones 23 . 24 respectively. 25 preferably the basic doping of the substrate.

For a thyristor according to the prior art results at a net dopant concentration of the n-doped base of 8.91 · 10 ¹² cm ^-3 and a blocking current of 100 mA a blocking voltage of 9.55 kV (curve 95 in 5 ). In contrast, can be with the thyristor of the invention, a significantly increased reverse voltage of 9.81 kV (maximum of the course 96 in 5 ), With the further embodiment of the thyristor according to the invention even achieve a blocking voltage of 9.92 kV (maximum of the course 97 in 5 ). At higher temperatures, the reverse voltage gain of a thyristor according to the invention increases even further compared to a conventional thyristor.

6 shows the course 81 the net dopant concentration N of a first field stop zone made according to a preferred method 21 depending on the distance from the irradiated semiconductor surface.

The production of this field stop zone 21 takes place here by front-side implantation of protons and a subsequent annealing step by annealing the semiconductor body at temperatures of 300 ° C to 450 ° C. As a result of the proton irradiation, donors are formed which can be used to generate such field stop zones. At a location S1 of the doping profile, the field stop zone 21 a maximum net dopant concentration N _max .

In the same way, the second field stop zone 22 according to the 1 and 2 through one from the back 12 outgoing proton irradiation with subsequent annealing at temperatures of 300 ° C to 450 ° C are produced.

In the 1 to 5 the inventive construction of a semiconductor device with two field stop zones has been explained using the example of a thyristor. However, the explanations for this can also be correspondingly transferred to any other semiconductor components, in particular MOSFETs and IGBTs. With IGBTs with such an arrangement and dimensioning of the second semiconductor zone, in particular the field stop zones, a reduction of the forward losses to 60% of the forward losses relative to the sheet resistance in the second semiconductor zone of a conventional NPT IGBT can be achieved (NPT = Non Punch Through).

The 7 to 11 show the courses 81 different net dopant concentrations N, which are at least partially realized in the semiconductor devices according to the invention.

The history 81 the net dopant concentration N according to 7 shows a heavily p-doped first semiconductor zone 10 and a heavily p-doped third semiconductor zone 30 between which an n-doped second semiconductor zone having heavily n-doped first and second field stop zones 21 . 22 as well as weakly n-doped subzones 23 . 24 and 25 is arranged.

The heavily n-doped first subzone 21 represents the first field stop zone, the second heavily n-doped subzone 22 the second field stop zone. The third subzone 23 is between the first semiconductor zone 10 and the first field stop zone 21 , the fourth sub-zone 24 between the third semiconductor zone 30 and the second field stop zone 22 arranged. Furthermore, the fifth sub-zone 25 between the first field stop zone 21 and the second field stop zone 22 arranged.

The subzones 23 . 24 , and 25 preferably have the same net dopant concentration N. In addition, the first field stop zone 21 and the second field stop zone 22 Set S1 and S2, respectively, at which the net dopant concentration N within the respective field stop zones 1 and 2 assumes a maximum N _max1 or N _max2 . The net dopant concentrations N _max1 and N _{max2 of} the first and second field stop zones, respectively 21 respectively. 22 are preferably selected identically.

In contrast to 7 shows the course 81 the net dopant concentration N according to 8th an embodiment in which the net dopant concentration of the third sub-zone 23 is greater than the net dopant concentration of the fourth sub-zone 24 and the fifth sub-zone 25 , The net dopant concentration within the second semiconductor zone 20 is thus - deviating from the embodiment according to 7 - unbalanced.

Alternatively to the course 81 according to 7 may be the net dopant concentration of the fifth sub-zone 25 also greater than the net dopant concentration of the fourth sub-zone 24 , in particular as large as the net dopant concentration of the third sub-zone 23 to get voted.

The embodiment according to 9 corresponds to the embodiment according to 8th with the difference that the first field stop zone 21 and the second field stop zone 22 directly adjacent to one another, which indicates that the net dopant concentration of the fifth sub-zone 25 greater than any of the net dopant concentrations of the third sub-zone 23 and the fourth sub-zone 24 ,

Decreasing starting from the embodiment according to 7 the distance between the points S1 and S2 maximum net dopant concentration of the first and second field stop zone 21 respectively. 22 , so the field stop zones overlap 21 . 22 in the limit, ie the first field stop zone 21 and the second field stop zone 22 are identical, which results in 10 is shown.

Starting from the embodiment according to 9 results in such a reduction of the distance of the points S1, S2 maximum net dopant concentration of the field stop zones 21 respectively. 22 a course 81 as he is in 11 is shown.

Next to the course 81 the net dopant concentration N is in the 7 to 11 also the course 82 the magnitude of the electric field strength E with voltage applied in the forward direction and the course 83 the magnitude of the electric field strength E at voltage applied in the reverse direction. In any case, the magnitude of the gradient of the electric field E in the vertical direction v increases with increasing net dopant concentration.

The embodiments according to the 7 to 11 are chosen so that the first semiconductor zone 10 directly to the front 11 and the third semiconductor zone 30 directly to the back 12 of the semiconductor body adjoins. In general, however, in a semiconductor device according to the invention between the front 11 and the first semiconductor zone 10 and / or between the back 12 and the third semiconductor zone 30 one or more further semiconductor zones may be provided in each case.

An embodiment of this shows 12 in the form of a vertical section through a section of the semiconductor body 1 a semiconductor device according to the invention.

In this device is between the first semiconductor zone 10 and the front 11 a zone 40 and between the third semiconductor zone 30 and the back 12 a zone 50 arranged. The zones 40 . 50 are each optional and may be provided independently of each other or in combination with each other. Each of the zones 40 . 50 may include any other device structures such as cell structures of a MOSFET or an IGBT, firing stages of a thyristor or insulating layers.

Furthermore, the embodiment according to FIG 12 in that a field stop zone according to the invention does not necessarily have to be formed as a continuous, coherent layer, but rather that it may also have a structured design.

In the embodiment according to 12 is each of the field stop zones 21 . 22 formed of a number of heavily n-doped islands, each substantially in a plane AA 'and BB' in a direction perpendicular to the vertical direction v lateral direction r spaced from each other in the second semiconductor zone 20 are arranged. Preferably, the first field stop zone 21 and the second field stop zone 22 identically structured, what made 13 it can be seen which a cross section through the sectional plane AA 'or by the sectional plane BB' according to 12 represents.

In principle, the first and the second field stop zone 21 respectively. 22 be formed independently of each other both the same and differently structured or unstructured.

So shows, for example 14 a vertical section through a portion of an IGBT, wherein the first field stop zone 21 , the third sub-zone 23 , the first semiconductor zone 10 and a fourth semiconductor zone 40 are structured to produce a cell structure of the IGBTs. The production of the first field stop zone 21 can be done for example by a masked implantation of protons and a subsequent annealing-annealing step. Depending on the intended depth and the intended thickness of the field stop zone to be produced 21 can implant from the front 11 and / or according to the embodiment according to the 16a to 16c from an implantation into a partial body of the semiconductor body to be produced 1 followed by wafer bonding.

The IGBT has a source electrode 61 , a drain electrode 62 and a gate electrode 63 on, as well as between the gate electrode 63 and the semiconductor body 1 arranged gate dielectric 64 ,

The embodiment according to 15 corresponds to the embodiment according to 14 with the difference that the first field stop zone 21 and the fifth subzone 25 are formed as substantially planar layers extending in the lateral direction r.

The production of a semiconductor component according to the invention can be carried out in various ways. In the simplest case, all or some of the semiconductor layers 10 . 20 . 30 including the first, second, third, fourth and fifth sub-zones 21 to 25 be built epitaxially in succession.

Another possibility is, in a semiconductor body having a weak n-type base doping, the first semiconductor zone 10 , the third semiconductor zone 30 , and optionally optional fourth semiconductor zones 40 and fifth semiconductor zones 50 by diffusion and / or implantation steps to produce.

The production of the heavily n-doped field stop zones 21 . 22 may be due to deep implantation of protons followed by tempering at Tempe temperatures between 300 ° C and 450 ° C are generated. This will be the first field stop zone 21 preferably by front side, the second field stop zone 22 preferably generated by backside proton implantation. As a result of the implantation of protons followed by the annealing, donors are formed in the area of the implantation area, resulting in the generation of the field stop zones 21 . 22 can be used.

A further alternative for producing a semiconductor component according to the invention with two field stop zones is disclosed in US Pat 16a to 16c shown. In this case, the semiconductor body 1 produced by wafer bonding, by a first part body 1' and a second part body 1'' be joined together.

Each of the part bodies 1' and 1'' has a weak n-basic doping. How out 16a it can be seen, protons 70 both in one zone 21 ' of the first part body 1' as well as in a zone 22 of the second part body 1'' implanted. In order to achieve a predefined structuring of the first and / or second field stop zone to be produced, the implantation of the protons can also take place masked.

16b shows the part bodies 1' . 1'' after implantation, which are joined together so that the in 16c shown component results.

The annealing step required after the implantation of the protons can take place both before and after the joining of the part bodies 1 . 1'' according to 16b respectively.

The The present invention has been based on devices with two field stop zones described. in principle however, the number of field stop zones can be arbitrarily selected. Further field stop zones are preferably between the first and the second field stop zone as further sub-zones of the second semiconductor zone intended.

In addition, can in all semiconductor devices according to the invention the production of the first and / or the second and optionally one or several other field stop zones by means of a masked implantation of protons and a subsequent annealing annealing step.

1

Semiconductor body

1'

first partial body of the semiconductor body

1''

second partial body of the semiconductor body

10

first Semiconductor zone

11

front of the semiconductor body

12

back of the semiconductor body

20

second Semiconductor zone

21

first Partial zone of the second semiconductor zone (first field stop zone)

21 '

Zone of the first part body

22

second Partial zone of the second semiconductor zone (second field stop zone)

22 '

Zone of the second part body

23

third Sub-zone of the second semiconductor zone

24

fourth Sub-zone of the second semiconductor zone

25

fifth subzone the second semiconductor zone

30

third Semiconductor zone

40

fourth Semiconductor zone

50

fifth semiconductor zone

61

Source electrode

62

Drain

63

Gate electrode

64

Gate dielectric

70

protons

81

course the net dopant concentration

82

course of the electric field in the forward direction

83

course of the electric field in the reverse direction

90

Current-voltage characteristic in the reverse direction (conventionally designed thyristor)

91

Current-voltage characteristic in the reverse direction (inventively designed thyristor)

92

course of the electric field (conventionally designed thyristor)

93

course of the electric field (thyristor designed according to the invention)

95

reverse voltage a thyristor according to the state technology with a reverse current of 100 mA

96

dependence from the blocking voltage of a thyristor according to the invention in a reverse current of 100 mA from the net doping dose of the field stop zone

97

dependence the blocking voltage of a thyristor according to the invention in a reverse current of 100 mA from the net doping dose of the field stop zone

A-A '

cutting plane

B-B '

cutting plane

d1

thickness the first field stop zone in the vertical direction

d2

thickness the second field stop zone in the vertical direction

d20

thickness the second semiconductor zone

d23

thickness the third semiconductor region in the vertical direction

d24

thickness the fourth semiconductor region in the vertical direction

d25

thickness the fifth Semiconductor zone in the vertical direction

e

electrical field

N

Net dopant concentration

N _max1

maximum Net dopant concentration of the first field stop zone

N _max2

maximum Net dopant concentration of the second field stop zone

r

lateral direction

S1

Job maximum net dopant concentration of the first field stop zone

S2

Job maximum net dopant concentration of the second field stop zone

t1

vertical spacing the location of the maximum net dopant concentration the first field stop zone from the front

t2

vertical spacing the location of the maximum net dopant concentration the second field stop zone from the back

t3

vertical spacing the location of maximum net dopant concentration the first field stop zone from the point of maximum net dopant concentration the second field stop zone

v

vertical direction

Claims (39)

Semiconductor device having a semiconductor body ( 1 ), in which between a front side ( 11 ) and one of the front ( 11 ) opposite back ( 12 ) in a vertical direction (v) a first semiconductor zone ( 10 ) of a first conductivity type (p), a second semiconductor region ( 20 ) of a first conductivity type (p) complementary second conductivity type (n), and a third semiconductor zone ( 30 ) of the first conductivity type (p) are arranged successively, wherein the second semiconductor zone ( 20 ) - a first field stop zone ( 21 ) of the second conductivity type (s), which differs from the first semiconductor region ( 10 ) and that has a higher net dopant concentration than that between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ), as well as - a second field stop zone ( 22 ) of the second conductivity type (n), that of the third semiconductor zone ( 30 ) and that has a higher net dopant concentration than that between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged section ( 24 ) of the second semiconductor zone ( 20 ). Semiconductor component according to Claim 1, in which the doping dose of the first field stop zone ( 21 ) and / or the second field stop zone ( 22 ) is 0.25 times to 0.75 times the breakthrough doping dose. Semiconductor component according to Claim 1 or 2, in which the doping dose of the first field stop zone ( 21 ) and / or the second field stop zone ( 22 ) is 0.4 times to 0.6 times the breakthrough doping dose. Semiconductor component according to one of the preceding claims, in which the doping dose of the first field stop zone ( 21 ) and / or the second field stop zone ( 22 ) is between 1.3 × 10 ¹² cm ^-2 and 2 × 10 ¹² cm ^-2 . Semiconductor component according to one of the preceding claims, in which the distance of the first field stop zone ( 21 ) from the front ( 11 ) 10% to 30% of the thickness of the second semiconductor zone ( 20 ) is. Semiconductor component according to one of the preceding claims, wherein the distance of the second field stop zone ( 22 ) from the back ( 12 ) 10% to 30% of the thickness of the second semiconductor zone ( 20 ) is. Semiconductor component according to one of the preceding claims, wherein the between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) has a net dopant concentration of less than or equal to 1 × 10 ¹⁴ cm ^-3 . A semiconductor device according to claim 7, wherein the between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) has a net dopant concentration of less than or equal to 1 × 10 ¹³ cm ^-3 . Semiconductor component according to one of the preceding claims, wherein the between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) has a dopant dose of less than or equal to 25% of the breakdown doping dose. Semiconductor component according to one of the preceding claims, wherein the between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged section ( 24 ) of the second semiconductor zone ( 20 ) has a net dopant concentration of less than or equal to 1 × 10 ¹⁴ cm ^-3 . A semiconductor device according to claim 10, wherein the between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged section ( 24 ) of the second semiconductor zone ( 20 ) has a net dopant concentration of less than or equal to 1 × 10 ¹³ cm ^-3 . Semiconductor component according to one of the preceding claims, wherein the between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged section ( 24 ) of the second semiconductor zone ( 20 ) has a dopant dose of less than or equal to 25% of the breakdown doping dose. Semiconductor component according to one of the preceding claims, wherein the between the first field stop zone ( 21 ) and the second field stop zone ( 22 ) arranged section ( 25 ) of the second semiconductor zone ( 20 ) has a net dopant concentration of less than or equal to 1 × 10 ¹⁴ cm ^-3 . A semiconductor device according to claim 13, wherein the between the first field stop zone ( 21 ) and the second field stop zone ( 22 ) arranged section ( 25 ) of the second semiconductor zone ( 20 ) has a net dopant concentration of less than or equal to 1 × 10 ¹² cm ^-2 . Semiconductor component according to one of the preceding claims, wherein the between the first field stop zone ( 21 ) and the second field stop zone ( 22 ) arranged section ( 25 ) of the second semiconductor zone ( 20 ) has a dopant dose of less than or equal to 25% of the breakdown doping dose. Semiconductor component according to one of the preceding claims, wherein the between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) and between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged section ( 24 ) of the second semiconductor zone ( 20 ) have identical net dopant concentrations. Semiconductor component according to one of claims 1 to 15, at. that between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) has a maximum net dopant concentration that is higher than a maximum net dopant concentration of the between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged portion ( 24 ) of the second semiconductor zone ( 20 ). Semiconductor component according to one of Claims 1 to 15, in which the device between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) has a maximum net dopant concentration that is less than a maximum net dopant concentration of the between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged portion ( 24 ) of the second semiconductor zone ( 20 ). Semiconductor component according to one of the preceding claims, wherein the between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) and between the third semiconductor zone ( 30 ) and the second field stop zone ( 22 ) arranged section ( 24 ) of the second semiconductor zone ( 20 ) in the vertical direction (v) have identical dimensions (d23, d24). Semiconductor component according to one of the preceding claims, in which the first field stop zone ( 21 ) has a position (S1) of maximum net dopant concentration, which is from the front ( 11 ) is spaced as far as a point (S2) of maximum net dopant concentration of the second field stop zone (FIG. 22 ) from the back ( 12 ). Semiconductor component according to one of Claims 1 to 19, in which the first field stop zone ( 21 ) has a position (S1) of maximum net dopant concentration farther from the front ( 11 ) is spaced as a location (S2) of maximum net dopant concentration of the second field stop zone (FIG. 22 ) from the back ( 12 ). Semiconductor component according to one of Claims 1 to 19, in which the first field stop zone ( 21 ) has a location (S1) of maximum net dopant concentration less far from the front ( 11 ) is spaced as a location (S2) of maximum net dopant concentration of the second field stop zone (FIG. 22 ) from the back ( 12 ). Semiconductor component according to one of the preceding claims, in which the first field stop zone ( 21 ) is formed as a continuous layer or strip-like or net-like or has a number of spaced-apart islands. Semiconductor component according to one of the preceding claims, in which the second field stop zone ( 22 ) is formed as a continuous layer or strip-like or net-like or has a number of spaced-apart islands. Semiconductor component according to one of the preceding claims, in which the first field stop zone ( 21 ) and the second field stop zone ( 22 ) are spaced from each other. Semiconductor component according to one of Claims 1 to 24, in which the first field stop zone ( 21 ) and the second field stop zone ( 22 ) directly adjoin one another. Semiconductor component according to one of Claims 1 to 24, in which the first field stop zone ( 21 ) and the second field stop zone ( 22 ) are identical. Semiconductor component according to one of the preceding claims, in which between the front side ( 11 ) and the first semiconductor zone ( 10 ) a fourth semiconductor zone ( 40 ) is arranged. Semiconductor component according to Claim 28, in which the fourth semiconductor zone ( 40 ) of the second conductivity type (s). Semiconductor component according to Claim 28 or 29, in which the fourth semiconductor zone ( 40 ) is structured in a lateral direction (r) perpendicular to the vertical direction (v). Semiconductor component according to Claim 29 or 30, which is designed as a thyristor, in which the first semiconductor zone ( 10 ) and the second semiconductor zone ( 20 ) the base zones and the third semiconductor zone ( 30 ) and the fourth semiconductor zone ( 40 ) form the emitter zones of the thyristor. Semiconductor component according to one of Claims 1 to 30, which is designed as an IGBT. Semiconductor component according to Claim 32, in which the first semiconductor zone ( 10 ) and / or the first field stop zone ( 21 ) and / or between the first semiconductor zone ( 10 ) and the first field stop zone ( 21 ) arranged section ( 23 ) of the second semiconductor zone ( 20 ) is structured to form IGBT cells. Semiconductor component according to one of the preceding Claims, in which the first conductivity type is "n" and the second conductivity type is "p" or in which the first conductivity type is "p" and the second conductivity type is "n". Method for producing a semiconductor component according to one of the preceding claims, in which the first field stop zone ( 21 ) and / or the second field stop zone ( 22 ) is produced by means of a proton implantation. Method according to claim 35, in which the proton implantation for producing the first field stop zone ( 21 ) and / or the proton implantation for the production of the second field stop zone ( 22 ) is masked. Method for producing a semiconductor component according to one of Claims 1 to 34, comprising the following steps: providing a first part-semiconductor body ( 1' ) and a second partial semiconductor body ( 1'' ) - introducing a doping of the second conductivity type (s) causing substances in a first zone ( 21 ' ) of the first part semiconductor body ( 1' ) starting from a front side ( 11 ' ) of the first semiconductor body ( 1' ), Introducing a doping of the second conductivity type (s) of causing substances into a first zone ( 22 ' ) of the second partial semiconductor body ( 1'' ) starting from a front side ( 11 '' ) of the second semiconductor body ( 1' ), - connecting the front sides ( 11 ' . 11 '' ) of the first part semiconductor body ( 1' ) and the second partial semiconductor body ( 1'' ) for the production of the semiconductor body ( 1 ). Method according to Claim 37, in which the first zone ( 21 ' ) of the first part semiconductor body ( 1' ) and / or the first zone ( 22 ' ) of the second partial semiconductor body ( 1'' ) from the front ( 11 ' . 11 '' ) of the respective partial semiconductor body ( 1' . 1'' ) is spaced. A method according to claim 37 or 38, wherein the Introducing a doping of the second conductivity type (s) effecting Substances by implantation and / or by diffusion takes place.