JP2001332627A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a trimming element which can carry out trimming in response to the needs in a high precisim LSI, can increase yields of LSIs, and can reduce the manufacturing cost. SOLUTION: In the trimming element which consists of a series combination of a Zener zap diode 10a and a fuse element 12a, a destruction short-circuit current Izap o the Zener zap diode is set smaller than a blow-out current Ifuse of the fuse element. In a first trimming, the current It is so controlled as to meet Izap<It<Ifuse, thus destructing and short-circuiting the Zener zap diode 10a while not melting the fuse element 12a, resulting in electrically short- circuiting the trimming element which is electrically open before trimming. In a second trimming, the current It is so controlled as to meet It<Ifuse, thus melting the fuse element 12a which was then not melted, resulting in the trimming element coming back to an electrically open state again. Consequently, trimming can be done twice on the same trimming element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device,
In particular, the present invention relates to a trimming element of a semiconductor integrated circuit.

[0002]

2. Description of the Related Art In recent electrical appliances, in order to reduce the number of components as much as possible, it is required that an LSI (large-scale integrated circuit) to be used has high accuracy. However, in the course of manufacturing an LSI, a certain level of manufacturing variation error is unavoidable, and as a result, the performance of the LSI also varies. As a technique for reducing such variation in LSI performance, there is a trimming technique for adjusting a resistance value or a capacitance value using a Zener Zap Diode or a fuse (Fuse) element.

[0003]

However, in actual trimming, the measured values before trimming vary due to variations in the contact resistance between the probe and the pads of the LSI, etc., so that the characteristics after trimming deviate from the desired characteristics. It often happens. In such a case, in the related art, since the trimming can be performed only once, the drive of the LSI characteristics becomes insufficient, the characteristics of the LSI products vary widely, and the yield thereof increases. Got worse.

[0004] Particularly, in a situation where higher precision of the LSI is required in recent years, it is difficult to take a sufficient measure by the conventional trimming technique. Then, a high-precision LSI with good characteristics is maintained with insufficient trimming.
If it is required to select and ship the products, there is a problem that the yield is reduced and the manufacturing cost is increased.

Accordingly, the present invention has been made in view of the above problems, and realizes trimming that can sufficiently cope with a high-precision LSI, thereby improving the yield of the LSI and reducing the manufacturing cost. It is an object of the present invention to provide a trimming element capable of performing the following.

[0006]

The above object is achieved by a semiconductor device according to the present invention described below. That is,
A semiconductor device according to a first aspect is characterized in that a Zener zap diode and a fuse element are connected in series, and a current for breaking and short-circuiting the Zener zap diode is smaller than a fusing current of the fuse element.

As described above, in the semiconductor device according to the first aspect, the Zener zap diode and the fuse element are connected in series, and a current for breaking and shorting the Zener zap diode (hereinafter, referred to as a "destructive short circuit current") is supplied to the fuse element. For example, when trimming is performed using an intermediate value between the destruction short-circuit current of the Zener zap diode and the fusing current of the fuse element from an electrically open state before trimming, Although the Zener zap diode is destructively short-circuited, the other fuse element is not blown, and the entire trimming element is electrically short-circuited, so that the trimming can be performed again.

Accordingly, in a high-precision LSI, even if the trimming of the LSI is not sufficient by one trimming, the trimming of the LSI can be sufficiently performed by the second trimming. And the production cost is reduced.

In a semiconductor device according to a second aspect of the present invention, the Zener zap diode and the fuse element are connected in parallel, and a fusing voltage of the fuse element is smaller than a voltage at which the Zener zap diode is broken and short-circuited.

As described above, in the semiconductor device according to the second aspect, the zener zap diode and the fuse element are connected in parallel, and the fusing voltage of the fuse element causes a voltage that causes the zener zap diode to break and short-circuit (hereinafter referred to as a “breakdown short-circuit voltage”). "), The trimming is performed using an intermediate value between the fusing voltage of the fuse element and the destruction short-circuit voltage of the Zener zap diode, for example, from an electrically shorted state before trimming. Although the fuse element is blown, the other Zener zap diode is not destructively short-circuited, and the entire trimming element is electrically opened, so that the trimming can be performed again.

Therefore, in a high-precision LSI, even if the trimming of the LSI is insufficient by one trimming, the trimming of the LSI can be sufficiently adjusted by the second trimming. And the production cost is reduced.

In the semiconductor device according to claim 1 or 2, the cathode (Ca)
thode) In the extraction part and the fuse part of the fuse element,
It is preferable that the same polycrystalline silicon layer is also used.

In this case, the trimming element in which the Zener zap diode and the fuse element are combined is downsized, which contributes to high integration of the semiconductor device, suppresses an increase in the number of steps in the manufacturing process, and reduces the manufacturing cost. It also contributes to the reduction of

Further, in the semiconductor device according to claim 1 or 2, the anode of the Zener zap diode (An
ode) It is also preferable that the same polycrystalline silicon layer is also used for the take-out portion and the fuse portion of the fuse element.

Also in this case, the trimming element in which the Zener zap diode and the fuse element are combined is downsized, which contributes to high integration of the semiconductor device, suppresses an increase in the number of steps in the manufacturing process, and reduces the manufacturing cost. It also contributes to the reduction of

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described. (First Embodiment) FIG. 1 is an equivalent circuit diagram showing a trimming element according to a first embodiment of the present invention, FIG. 2 is a schematic plan view showing the trimming element of FIG. 1, and FIG. 3 is a trimming element of FIG. FIG. 2 is a schematic plan view showing a cross section taken along line AA of FIG.

As shown in FIG. 1, in the trimming element according to the present embodiment, a Zener zap diode 10a and a fuse element 12a are connected in series. The destruction short-circuit current Izap of the Zener zap diode 10a is determined by the fusing current Iz of the fuse element 12a.
It is characterized in that it is smaller than fuse, that is, Izap <Ifuse.

The trimming element shown in FIG. 1 is specifically configured as shown in FIGS. Here, only the main components of the trimming element are shown, and the other components are not shown as appropriate. That is, an N-type buried layer 102 is formed on the P-type semiconductor substrate 100, and an N-type collector region 104 made of an N-type epitaxial layer is formed on the P-type semiconductor substrate 100 and the N-type buried layer 102. I have. The N-type collector region 104 is separated by a P-type device isolation region 106 to define a device region.
A field oxide film 108 is formed on a part of the N-type collector region 104 and on the P-type element isolation region 106.

The N-type collector region 1 in the element region
On the surface of the element 04, a P-type genuine base region serving as an anode of the Zener zap diode 10a and a P-type base region 110 consisting of a P-type external base region, an N-type emitter region 112 serving as a cathode of the Zener zap diode 10a, and an N-type collector extraction Regions 114 are respectively formed. An insulating film 116 is formed on the N-type collector region 104, the P-type base region 110, the N-type emitter region 112, and the N-type collector extraction region 114.

Further, a conductive polycrystalline silicon layer connected to the P-type base region 110, the N-type emitter region 112, and the N-type collector extraction region 114 through the opening formed in the insulating film 116, respectively. P-type polycrystalline silicon base contact portion 118a, N-type polycrystalline silicon emitter contact portion 118b, N-type polycrystalline silicon collector contact portion and fuse portion 118c
Are formed. The N-type polycrystalline silicon collector contact / fuse portion 118c connected to the N-type collector extraction region 114 extends to the field oxide film 108 located in the opposite direction to the N-type emitter region 112. Are there.

These insulating film 116, P-type polycrystalline silicon base contact 118a, N-type polycrystalline silicon emitter contact 118b, N-type polycrystalline silicon collector contact and fuse 118c,
And an interlayer insulating film 120 on the field oxide film 108.
Are formed.

Contact windows 122a, 122b, 122c, 122d opened in interlayer insulating film 120 are provided.
Through the P-type polysilicon base contact portion 1
An emitter / collector electrode / fuse electrode 124b connected to one end of the base electrode 124a connected to the N-type polycrystalline silicon emitter contact portion 118b and the N-type polycrystalline silicon collector contact portion / fuse portion 118c; A fuse electrode 124c connected to the other end of the polycrystalline silicon collector contact portion and fuse portion 118c is formed.

The P-type polycrystalline silicon base contact portion 118a is connected to the Zener zap diode 10a.
Of the base electrode 124a
Functions as an anode electrode of the Zener zap diode 10a. Also, N-type polycrystalline silicon
The emitter contact portion 118b and the N-type polycrystalline silicon collector contact portion (also serving as a fuse portion) 118c
Both functions as a cathode extraction portion of the zener zap diode 10a, and the emitter / collector electrode (also serves as a fuse electrode) 124b functions as a cathode electrode of the zener zap diode 10a.

N-type polycrystalline silicon (collector contact portion) fuse portion 118c is connected to fuse element 12
a, and the fuse electrode 124b (also serving as an emitter / collector electrode) is connected to the fuse element 12a.
Function as one of the fuse electrodes. The fuse electrode 124c functions as the other fuse electrode of the fuse element 12a.

That is, the base electrode 124a functioning as the anode electrode of the Zener zap diode 10a is connected to the P-type base region 1 via the P-type polycrystalline silicon base contact portion 118a functioning as the anode extraction portion.
10 is connected. An emitter / collector electrode (also serving as a fuse electrode) 124b functioning as a cathode electrode of the Zener zap diode 10a includes an N-type polycrystalline silicon emitter contact portion 118b and an N-type polycrystalline silicon collector contact portion functioning as a cathode extraction portion. The N-type emitter region 112 and the N-type collector take-out region 114 are provided via a (cum fuse) 118c.
Connected to both. Therefore, the N-type emitter region 112 and the N-type collector extraction region 114 are in a short-circuit state.

The fuse electrode 124b and the fuse electrode 124c functioning as the two fuse electrodes (emitter / collector electrode) of the fuse element 12a are formed of N-type polycrystalline silicon (collector contact portion) functioning as the fuse part. 118c are connected to both ends.

Although not shown, the interlayer insulating film 120 and the base electrode 12 functioning as an anode
4a, an emitter / collector electrode / fuse electrode 124b functioning as a cathode electrode and one fuse electrode;
On the other fuse electrode 124c, an upper wiring and a passivation film are formed.

Thus, the Zener zap diode 10
a and the fuse element 12a are formed respectively, and further, the zener zap diode 10a and the fuse element 12a are connected in series.

Although not shown, the base electrode 124a functioning as the anode electrode of the Zener zap diode 10a and the fuse electrode 124c of the fuse element 12a are connected to the probe pads, respectively, so that a predetermined bias is applied. Has become.

Next, the operation of the trimming element shown in FIGS. 1 to 3 will be described. This zener zap diode 1
The trimming element in which Oa and the fuse element 12a are connected in series is electrically open before the trimming. Then, in the first trimming, the applied current It flows between the base electrode 124a functioning as the anode electrode of the Zener zap diode 10a and the fuse electrode 124c of the fuse element 12a. At this time, the value of the applied current It is controlled so that Izap <It <Ifuse.

For this reason, one Zener zap diode 10a is destructively short-circuited, while the other fuse element 1
2a does not blow. Therefore, as a trimming element,
An electric short circuit occurs, and trimming can be performed again.

Subsequently, the second trimming is performed. At this time, the value of the applied current It is controlled such that It> Ifuse. For this reason, the fuse element 12a which has not been blown yet in the first trimming.
Is blown. Therefore, the trimming element is electrically opened again.

As described above, according to the present embodiment, in the trimming element in which the zener zap diode 10a and the fuse element 12a are connected in series, the destruction short-circuit current Izap of the zener zap diode 10a is blown by the fuse element 12a. Smaller than the current Ifuse,
That is, by setting Izap <Ifuse, the value of the applied current It in the first trimming is controlled so as to be Izap <It <Ifuse, so that one Zener zap diode 10a is broken and short-circuited, and the other fuse element 12a is connected. Without fusing, the electrically open trimming element before trimming is electrically short-circuited, so that trimming can be performed again, and the value of the applied current It for the second trimming is such that It> Ifuse. By controlling, the fuse element 12a that has not been blown in the first trimming is blown, and the trimming element can be electrically opened again.

As described above, two trimmings can be performed by one trimming element, so that a high-precision LSI
However, it is possible to sufficiently drive the characteristics of the LSI. Therefore, it is possible to improve the yield of high-precision LSI and reduce the manufacturing cost.

The zener zap diode 10a and the fuse element 12a forming the trimming element according to the present embodiment are composed of an n-type buried layer 102 formed on a p-type semiconductor substrate 100, an n-type collector region 104, a zener zap diode 10a. P-type base region 110 serving as an anode, and N-type emitter region 112 serving also as a cathode
And N-type collector extraction region 114, P-type polycrystalline silicon base contact portion 118a, N-type polycrystalline silicon emitter contact portion 118b, N-type polycrystalline silicon collector contact portion and fuse portion 118c, anode of zener zap diode 10a A base electrode 124a functioning as an electrode, and an emitter / collector electrode (also serving as a fuse electrode) 12 also functioning as a cathode electrode
4b, fuse electrode 1 functioning as two fuse electrodes of fuse element 12a (also serving as emitter / collector electrode)
LS having a well-known polycrystalline silicon contact layer because it is composed of
Since it can be formed easily and simultaneously without adding any new steps to the manufacturing process of I, an increase in cost due to an increase in the number of steps can be suppressed.

The N-type polycrystalline silicon collector contact / fuse portion 118c functions not only as a cathode extraction portion of the Zener zap diode 10a but also as a fuse portion of the fuse element 12a. Electrode and fuse electrode 1
Reference numeral 24b functions as a cathode electrode of the Zener zap diode 10a and also functions as one fuse electrode of the fuse element 12a. That is, the N-type polycrystalline silicon collector contact portion and fuse portion 1
18c is also used as a cathode extraction portion of the zener zap diode 10a and a fuse portion of the fuse element 12a. An emitter / collector electrode / fuse electrode 124b is used as a cathode electrode of the zener zap diode 10a and one fuse electrode of the fuse element 12a. As a result, the trimming element in which the zener zap diode 10a and the fuse element 12a are connected in series is downsized, which contributes to the high integration of an LSI including this trimming element and the manufacturing process thereof. In this case, the increase in the number of steps can be suppressed, thereby contributing to a reduction in manufacturing cost.

In the first embodiment, N
The N-type polycrystalline silicon collector contact / fuse portion 118c extends from the N-type collector extraction region 114 onto the field oxide film 108.
Instead of c, an N-type polysilicon emitter contact portion and a fuse portion extending from the N-type emitter region 112 onto the field oxide film 108 are formed, and the cathode extraction portion of the Zener zap diode 10a and the fuse of the fuse element 12a are formed. It may also be used as a unit. Further, a P-type polycrystalline silicon base contact portion and a fuse portion extending from the P-type base region 110 onto the field oxide film 108 are formed, and are also used as an anode extraction portion of the Zener zap diode 10a and a fuse portion of the fuse element 12a. May be.

Further, instead of using the cathode extraction portion or anode extraction portion of the Zener zap diode 10a and the fuse portion of the fuse element 12a in this manner,
A fuse portion of the fuse element 12a is formed on the field oxide film 108 separately from the cathode extraction portion and the anode extraction portion of the Zener zap diode 10a, and the fuse portion and the cathode extraction portion of the Zener zap diode 10a are formed using, for example, wiring. You may electrically connect with an anode extraction part, respectively.

In this case, in the fuse portion of the fuse element 12a formed separately from the cathode extraction portion and the anode extraction portion of the zener zap diode 10a, these are formed simultaneously with the cathode extraction portion and the anode extraction portion. A P-type or N-type polycrystalline silicon layer may be used, a P-type or N-type polycrystalline silicon layer formed at a different time, or a different material may be used.

As described above, the first embodiment is as follows.
The present invention can be easily applied to a structure having no polycrystalline silicon contact layer, a two-layer polycrystalline silicon structure, and an LSI based on silicon germanium.

(Second Embodiment) FIG. 4 is an equivalent circuit diagram showing a trimming element according to a second embodiment of the present invention.
FIG. 5 is a schematic plan view showing the trimming element of FIG. Here, FIG. 4 corresponding to FIG. 3 of the first embodiment described above.
The schematic cross-sectional view of the trimming element is omitted, and the same elements as those of the trimming element of the first embodiment shown in FIGS.

As shown in FIG. 4, in the trimming element according to the present embodiment, a Zener zap diode 10b and a fuse element 12b are connected in parallel. Then, the fusing voltage Vfuse of the fuse element 12b is
Is the breakdown short-circuit voltage V of the Zener zap diode 10b.
It is characterized in that it is smaller than zap, that is, Vfuse <Vzap.

The trimming element shown in FIG. 4 is specifically configured as shown in FIG. That is,
As in the case of the first embodiment, the P-type semiconductor substrate 1
On the P-type semiconductor substrate 100 and the N-type buried layer 102, an N-type buried layer 102 is formed. The N-type collector region 104
A field oxide film 108 is formed on a part of the N-type collector region 104 and the P-type element isolation region 106.

Then, the N-type collector region 1 in the element region
On the surface of the substrate 04, a P-type genuine base region serving as an anode of the Zener zap diode 10b and a P-type base region 110 consisting of a P-type external base region, an N-type emitter region 112 serving as a cathode of the Zener zap diode, and an N-type collector extraction region 114 are formed.

The N-type collector region 104,
The P-type base region 110, the N-type emitter region 112, and the N-type collector are formed through openings in the insulating film 116 formed on the P-type base region 110, the N-type emitter region 112, and the N-type collector extraction region 114. Extraction area 1
14, a P-type polysilicon base contact portion 118a made of a P-type polysilicon layer connected to
-Type polycrystalline silicon emitter contact portion 118b, N
Form polycrystalline silicon collector contact portion 118d is formed.

Unlike the case of the first embodiment, a P-type or N-type polycrystalline silicon fuse portion 118e is formed on field oxide film 108. Also,
These insulating film 116, P-type polycrystalline silicon base contact portion 118a, N-type polycrystalline silicon emitter contact portion 118b, N-type polycrystalline silicon collector contact portion 118d, P-type or N-type polycrystalline silicon fuse portion An interlayer insulating film 120 is formed on 118 e and the field oxide film 108.

Also, contact windows 122a, 122b, 122c, 122 opened in interlayer insulating film 120 are formed.
e, 122f, the P-type polysilicon base contact portion 118a and the P-type or N-type polysilicon
Base electrode / fuse electrode 124d connected to one end of fuse portion 118e, P-type polysilicon emitter contact portion 118b, P-type polysilicon collector contact portion 118d, and P-type or N-type polysilicon fuse portion 118e And an emitter / collector electrode / fuse electrode 124e respectively connected to the other ends of the electrodes.

The P-type polycrystalline silicon base contact portion 118a is connected to the Zener zap diode 10b.
And a base electrode (also serving as a fuse electrode) 124d is connected to the zener zap diode 10d.
b functions as an anode electrode. Also, P
-Type polycrystalline silicon emitter contact portion 118b and P-type polycrystalline silicon collector contact portion 118d
Function as a cathode extraction portion of the zener zap diode 10b, and the emitter / collector electrode (also serves as a fuse electrode) 124e is connected to the zener zap diode 10b.
b functions as a cathode electrode. Also,
The fuse electrode 124d (also serving as a base electrode) and the fuse electrode 124e (also serving as an emitter / collector electrode) function as two fuse electrodes of the fuse element 12b.

That is, the base electrode (also serving as a fuse electrode) 124d functioning as the anode electrode of the Zener zap diode 10b is connected to the P-type base region 110 via the P-type polycrystalline silicon base contact portion 118a functioning as the anode extraction portion. It is connected to the. Further, an emitter / collector electrode (also serving as a fuse electrode) 12 functioning as a cathode electrode of the Zener zap diode 10b.
4e denotes an N-type polycrystalline silicon emitter contact portion 118b and an N-type polycrystalline silicon collector contact portion (also serving as a fuse portion) 11 functioning as a cathode extraction portion.
8c, it is connected to both the N-type emitter region 112 and the N-type collector extraction region 114. Therefore, the N-type emitter region 112 and the N-type collector extraction region 114 are in a short-circuit state.

The fuse electrode 1 which functions as two fuse electrodes of the fuse element 12b (also serves as a base electrode)
The fuse electrode 24d and the fuse electrode 124e (also serving as an emitter / collector electrode) are respectively connected to both ends of a P-type or N-type polycrystalline silicon fuse portion 118e functioning as a fuse portion.

Further, on the interlayer insulating film 120, the base electrode / fuse electrode 124d functioning as an anode electrode and one fuse electrode, and the emitter / collector electrode / fuse electrode 124e functioning as a cathode electrode and the other fuse electrode. Then, an upper wiring and a passivation film are formed.

Thus, the Zener zap diode 10
b and the fuse element 12b are formed respectively, and the zener zap diode 10b and the fuse element 12b are connected in parallel.

Although not shown, the anode electrode of the zener zap diode 10b and the fuse element 12
The base electrode / fuse electrode 124d functioning as one of the fuse electrodes b, the emitter / collector electrode / fuse electrode 124e functioning as the cathode electrode of the Zener zap diode 10b and the other fuse electrode of the fuse element 12b are connected to the probe pad, respectively. Then, a predetermined bias is applied.

Next, the operation of the trimming element shown in FIGS. 4 and 5 will be described. The trimming element in which the Zener zap diode 10b and the fuse element 12b are connected in parallel is electrically short-circuited before the trimming. And in the first trimming,
A base electrode / fuse electrode 124d functioning as an anode electrode of the zener zap diode 10b and one of the fuse electrodes of the fuse element 12b; a cathode electrode and the fuse element 12 of the zener zap diode 10b;
b, an applied voltage Vt between the emitter / collector electrode and the fuse electrode 124e functioning as the other fuse electrode.
multiply. Then, the value of the applied voltage Vt at this time is controlled so that Vfuse <Vt <Vzap.

For this reason, while one fuse element 12b blows, the other zener zap diode 10b
Does not cause a destructive short circuit. Therefore, as a trimming element,
The electric breakdown is released, and the trimming can be performed again.

Subsequently, the second trimming is performed. At this time, the value of the applied current voltage Vt is controlled so that Vt> Vzap. For this reason, the Zener zap diode 10b that has not been destructively short-circuited in the first trimming is destructively short-circuited. Therefore, the trimming element is electrically short-circuited again.

As described above, according to this embodiment, in the trimming element in which the zener zap diode 10b and the fuse element 12b are connected in parallel, the fusing voltage Vfuse of the fuse element 12b is reduced by the destruction short-circuit of the zener zap diode 10b. Lower than the voltage Vzap,
That is, by setting Vfuse <Vzap, the applied voltage Vt of the first trimming is set.
Is controlled so that Vfuse <Vt <Vzap, and one fuse element 12b is blown, and the other zener zap diode 10b is not destructively short-circuited. It becomes electrically open, and trimming can be performed again. Further, the value of the applied voltage Vt of the second trimming is controlled so that Vt> Vzap, and a destructive short circuit still occurs in the first trimming. The zener zap diode 10b that has not been broken can be short-circuited by destruction, and the trimming element can be electrically short-circuited again.

As described above, two trimmings can be performed by one trimming element, so that a high-precision LSI
However, it is possible to sufficiently drive the characteristics of the LSI. Therefore, it is possible to improve the yield of high-precision LSI and reduce the manufacturing cost.

The zener zap diode 10b and the fuse element 12b forming the trimming elements according to the present embodiment are composed of an n-type buried layer 102, an n-type collector region 104, and a zener zap diode 10b formed on a p-type semiconductor substrate 100. P-type base region 110 serving as an anode, and N-type emitter region 112 serving also as a cathode
And N-type collector extraction region 114, P-type polycrystalline silicon base contact portion 118a, N-type polycrystalline silicon emitter contact portion 118b, N-type polycrystalline silicon collector contact portion 118d, P-type or N-type polycrystalline silicon. Fuse portion 118e, base electrode (also serving as fuse electrode) 124d functioning as an anode electrode of zener zap diode 10b, and emitter / collector electrode (also serving as fuse electrode) also serving as a cathode electrode
A fuse electrode 124d (also serving as a base electrode) and a fuse electrode 124e (also serving as an emitter / collector electrode) that function as two fuse electrodes of the fuse element 12b.
And the like, it can be easily and simultaneously formed without adding any new process to the known process for manufacturing an LSI having a polycrystalline silicon contact layer. Can be suppressed from increasing due to an increase in the cost.

The base electrode and fuse electrode 124d
Functions as an anode electrode of the zener zap diode 10b and also functions as one fuse electrode of the fuse element 12b. The emitter / collector electrode / fuse electrode 124e functions as a cathode electrode of the zener zap diode 10b. , And functions as the other fuse electrode of the fuse element 12b. That is, the base electrode and the fuse electrode 124d
Are also used as the anode electrode of the Zener zap diode 10b and one of the fuse electrodes of the fuse element 12b.
24e is also used as the cathode electrode of the zener zap diode 10b and the other fuse electrode of the fuse element 12b, so that the trimming element in which the zener zap diode 10b and the fuse element 12b are connected in parallel is downsized. And contribute to the high integration of the LSI including the trimming element,
It is possible to suppress an increase in the number of steps in the manufacturing process and to contribute to a reduction in manufacturing cost.

In the second embodiment, the P functioning as a fuse portion of the fuse element 12b and serving as an anode extraction portion of the Zener zap diode 10b.
N-type polycrystalline silicon that functions as base polycrystalline silicon base contact portion 118a and cathode extraction portion.
Although a P-type or N-type polycrystalline silicon fuse portion 118e formed simultaneously with the emitter contact portion 118b and the N-type polycrystalline silicon collector contact portion 118d is used, the cathode of the Zener zap diode 10b is used instead. A P-type or N-type polycrystalline silicon layer formed at a different time from the extraction section and the anode extraction section or a different material may be used.

As described above, the second embodiment is
The present invention can be easily applied to a structure having no polycrystalline silicon contact layer, a two-layer polycrystalline silicon structure, and an LSI based on silicon germanium.

[0063]

As described above, according to the semiconductor device of the present invention, the following effects can be obtained. That is, according to the semiconductor device of the first aspect, the Zener zap diode and the fuse element are connected in series, and the breakdown short-circuit current of the Zener zap diode is smaller than the fusing current of the fuse element. When trimming is performed using a current between the destruction short-circuit current of the zener zap diode and the fusing current of the fuse element from a partially open state, one zener zap diode is destructively short-circuited while the other fuse is short-circuited. Since the element is not blown, and the entire trimming element is electrically short-circuited, trimming can be performed again. Therefore, even in a high-precision LSI, the characteristics of the LSI can be sufficiently improved. It is possible to improve the yield of LSI and reduce the manufacturing cost.

Further, according to the semiconductor device of the second aspect, the Zener zap diode and the fuse element are connected in parallel, and the fusing voltage of the fuse element is smaller than the breakdown short-circuit voltage of the Zener zap diode. If trimming is performed from the previous electrically short-circuited state by using a voltage having an intermediate value between the fusing voltage of the fuse element and the destructive short-circuit voltage of the Zener zap diode,
Although one fuse element is blown, the other zener zap diode is not destructively short-circuited, and is electrically opened as an entire trimming element, so that trimming can be performed again. It is possible to sufficiently drive the characteristics, to improve the yield of LSI and to reduce the manufacturing cost.

According to a third aspect of the present invention, there is provided the semiconductor device according to the first or second aspect, wherein the same polycrystalline silicon layer is formed in the cathode extraction portion of the Zener zap diode and the fuse portion of the fuse element. Also, the trimming element in which the Zener zap diode and the fuse element are combined can be made compact, which contributes to the high integration of the semiconductor device and suppresses the increase in the number of steps in the manufacturing process. As a result, it is possible to contribute to a reduction in manufacturing cost.

According to a fourth aspect of the present invention, in the semiconductor device according to the first or second aspect, the same polycrystalline silicon layer is formed in the anode extraction portion of the Zener zap diode and the fuse portion of the fuse element. Also, the trimming element in which the Zener zap diode and the fuse element are combined can be made compact, which contributes to the high integration of the semiconductor device and suppresses the increase in the number of steps in the manufacturing process. As a result, it is possible to contribute to a reduction in manufacturing cost.

[Brief description of the drawings]

FIG. 1 is an equivalent circuit diagram showing a trimming element according to a first embodiment of the present invention.

FIG. 2 is a schematic plan view showing the trimming element of FIG.

FIG. 3 is a schematic plan view showing a cross section taken along line AA of the trimming element of FIG. 2;

FIG. 4 is an equivalent circuit diagram illustrating a trimming element according to a second embodiment of the present invention.

FIG. 5 is a schematic plan view showing the trimming element of FIG.

[Explanation of symbols]

10a, 10b ... Zener zap diode, 12
a, 12b: fuse element, 100: P-type semiconductor substrate, 102: N-type buried layer, 104: N-type collector region, 106: P-type element isolation region, 108: field oxide film, 110 ... ... P-type base region serving as anode of zener zap diode 112... N-type emitter region serving as cathode of zener zap diode 1
14: N serving as cathode of Zener zap diode
Mold collector extraction region, 116... Insulating film, 118a
… P-type polycrystalline silicon base contact part that functions as an anode extraction part of a Zener zap diode,
118b... N-type polycrystalline silicon emitter contact portion functioning as a cathode extraction portion of a Zener zap diode, 118c... N-type polycrystalline silicon collector contact functioning as a cathode extraction portion of a Zener zap diode and a fuse portion of a fuse element Section / fuse section, 118d ... N-type polycrystalline silicon collector contact section functioning as a cathode extraction section of a zener zap diode, 118e ... P-type or N-type polycrystalline silicon fuse section functioning as a fuse element fuse section .. 120 interlayer insulating films 122a and 122
b, 122c, 122d, 122e, 122f... contact window, 124a... base electrode that functions as an anode electrode of a zener zap diode, 124b... cathode electrode of a zener zap diode and an emitter that functions as one fuse electrode of a fuse element / Collector electrode / fuse electrode, 124c... The other fuse electrode, 124d... Base electrode / fuse electrode functioning as an anode electrode of a zener zap diode and one fuse electrode of a fuse element, 124e. And an emitter / collector electrode and fuse electrode functioning as the other fuse electrode of the fuse element.

Claims (4)

[Claims] 1. A semiconductor device, wherein a Zener zap diode and a fuse element are connected in series, and a current for breaking and short-circuiting the Zener zap diode is smaller than a fusing current of the fuse element. 2. A semiconductor device, wherein a Zener zap diode and a fuse element are connected in parallel, and a fusing voltage of the fuse element is lower than a voltage causing a destructive short circuit of the Zener zap diode. 3. The semiconductor device according to claim 1, wherein the same polycrystalline silicon layer is used for both the cathode extraction portion of the Zener zap diode and the fuse portion of the fuse element. Semiconductor device. 4. The semiconductor device according to claim 1, wherein the same polycrystalline silicon layer is used for both the anode extraction portion of the Zener zap diode and the fuse portion of the fuse element. Semiconductor device.