JP2010050370A - Inspection method for semiconductor device, method for manufacturing semiconductor device and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for inspecting a semiconductor device for easily managing the manufacturing process of a semiconductor device by electrically inspecting the film thickness of an insulating film, and for quickly and easily specifying the factor of failure. <P>SOLUTION: The inspection method of the semiconductor device includes the steps of: preparing a semiconductor device having a conductive section interposing an insulating film; measuring the capacity of the insulating film by applying a voltage to the conductive section; and inspecting the film thickness of the insulating film based on the capacity of the insulating film. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a semiconductor device inspection method, a semiconductor device manufacturing method, and a semiconductor device.

  In recent years, in order to improve the degree of integration and characteristics of semiconductor devices, the trend of multilayer wiring has been increasing. In multilayer wiring, generally, upper and lower wirings are insulated and separated by an interlayer insulating film.

  Under such circumstances, inspection and management of the film thickness of the interlayer insulating film have become extremely important.

For example, Patent Document 1 discloses a method for optically measuring a film thickness in-line.
JP 2005-83834 A

  One of the objects of the present invention is to easily manage the manufacturing process of a semiconductor device by electrically inspecting the film thickness of the insulating film, and to identify the cause of the defect quickly and easily. An object of the present invention is to provide a semiconductor device inspection method, a semiconductor device manufacturing method, and a semiconductor device.

An inspection method for a semiconductor device according to the present invention includes:
Preparing a semiconductor device having a conductive portion sandwiching an insulating film;
Applying a voltage to the conductive portion to measure the capacitance of the insulating film;
Inspecting the thickness of the insulating film based on the capacity of the insulating film;
including.

  The method for inspecting a semiconductor device according to the present invention can easily manage the manufacturing process of the semiconductor device by electrically inspecting the film thickness of the insulating film, and further, quickly identify the cause of the failure, And it can be done easily.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
A first conductive part;
A first insulating film formed above the first conductive portion;
A second conductive portion formed above the first insulating film;
A second insulating film formed above the second conductive portion;
A third conductive portion formed above the second insulating film;
Including
The semiconductor device includes:
The first conductive portion;
The third conductive portion;
A conductive layer formed in a recess of the second insulating film and electrically connected to the third conductive portion;
A first monitor unit having
The step of measuring the capacity of the insulating film includes:
Measuring the capacitance by applying a voltage to the first conductive portion and the third conductive portion of the first monitor portion;
The step of inspecting the film thickness of the insulating film includes:
Based on the capacitance of the first monitor unit, the film thickness of the insulating film between the first conductive unit and the conductive layer of the first monitor unit can be inspected.

  In the description of the present invention, the word “upper” is, for example, “forms another specific thing (hereinafter referred to as“ B ”)“ above ”a specific thing (hereinafter referred to as“ A ”)”. Etc. In the description according to the present invention, in the case of this example, the case where B is directly formed on A and the case where B is formed on A via another are included. The word “upward” is used.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
The second conductive portion;
The third conductive portion;
A conductive layer formed in a contact hole of the second insulating film and electrically connected to the second conductive portion and the third conductive portion;
Including a contact portion having
The conductive layer of the first monitor unit is longer than the conductive layer of the contact unit,
By inspecting the film thickness of the insulating film between the first conductive part and the conductive layer of the first monitor part, the over-etching amount for forming the contact hole can be inspected.

In the inspection method of the semiconductor device according to the present invention,
A plurality of the conductive layers of the first monitor unit may be provided.

In the inspection method of the semiconductor device according to the present invention,
The width of the conductive layer of the first monitor unit may be the same as the width of the conductive layer of the contact unit.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
A second monitor unit having the first conductive unit and the third conductive unit;
The step of measuring the capacity of the insulating film includes:
Furthermore, the capacitance is measured by applying a voltage to the first conductive portion and the third conductive portion of the second monitor portion,
The step of inspecting the film thickness of the insulating film includes:
Inspecting the film thickness of the insulating film between the first conductive portion and the conductive layer of the first monitor portion based on the capacitance of the first monitor portion and the capacitance of the second monitor portion. Can do.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
The first conductive portion;
The third conductive portion;
A conductive layer formed in a recess of the second insulating film and electrically connected to the third conductive portion;
A third monitor unit having
The hole diameter of the recess in which the conductive layer of the third monitor unit is formed is larger than the hole diameter of the recess in which the conductive layer of the first monitor unit is formed,
The step of measuring the capacity of the insulating film includes:
Furthermore, the capacitance is measured by applying a voltage to the first conductive part and the third conductive part of the third monitor part,
The step of inspecting the film thickness of the insulating film includes:
Further, based on the capacitance of the third monitor unit, inspect the film thickness of the insulating film between the first conductive unit and the conductive layer of the third monitor unit,
The film thickness of the insulating film between the first conductive part and the conductive layer of the first monitor part, and the film thickness of the insulating film between the first conductive part and the conductive layer of the third monitor part. And the amount of overetching for forming the contact hole can be inspected.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
The first conductive portion;
The third conductive portion formed in the recess of the second insulating film;
A third monitor unit having
The hole diameter of the concave portion in which the third conductive portion of the third monitor portion is formed is larger than the hole diameter of the concave portion in which the conductive layer of the first monitor portion is formed,
The step of measuring the capacity of the insulating film includes:
Furthermore, the capacitance is measured by applying a voltage to the first conductive part and the third conductive part of the third monitor part,
The step of inspecting the film thickness of the insulating film includes:
Further, based on the capacitance of the third monitor unit, inspect the film thickness of the insulating film between the first conductive unit and the conductive layer of the third monitor unit,
The film thickness of the insulating film between the first conductive part and the conductive layer of the first monitor part, and the film thickness of the insulating film between the first conductive part and the conductive layer of the third monitor part. And the amount of overetching for forming the contact hole can be inspected.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
A fourth monitor unit having the first conductive unit and the second conductive unit;
The step of measuring the capacity of the insulating film includes:
Measuring a capacitance by applying a voltage to the first conductive portion and the second conductive portion of the fourth monitor portion;
The step of inspecting the film thickness of the insulating film includes:
Based on the capacitance of the fourth monitor unit, the thickness of the insulating film between the first conductive unit and the second conductive unit of the fourth monitor unit can be inspected.

In the inspection method of the semiconductor device according to the present invention,
The semiconductor device includes:
A fifth monitor unit having the second conductive unit and the third conductive unit;
The step of measuring the capacity of the insulating film includes:
Measuring the capacitance by applying a voltage to the second conductive portion and the third conductive portion of the fifth monitor portion;
The step of inspecting the film thickness of the insulating film includes:
Based on the capacitance of the fifth monitor unit, the thickness of the insulating film between the second conductive unit and the third conductive unit of the fifth monitor unit can be inspected.

In the inspection method of the semiconductor device according to the present invention,
The first conductive part is made of metal or polysilicon,
The second conductive part and the third conductive part may be made of metal.

In the inspection method of the semiconductor device according to the present invention,
The first conductive portion comprises an impurity region formed in a semiconductor substrate,
The second conductive part is made of polysilicon,
The third conductive part may be made of metal.

A method for manufacturing a semiconductor device according to the present invention includes:
Preparing a semiconductor device having a conductive portion sandwiching an insulating film;
Applying a voltage to the conductive portion to measure the capacitance of the insulating film;
Inspecting the thickness of the insulating film based on the capacity of the insulating film;
including.

A semiconductor device according to the present invention includes:
A semiconductor device including a monitor unit and a contact unit,
The semiconductor device includes:
A first conductive part;
A first insulating film formed above the first conductive portion;
A second conductive portion formed above the first insulating film;
A second insulating film formed above the second conductive portion;
A third conductive portion formed above the second insulating film;
Including
The monitor unit is
The first conductive part, the third conductive part, and a conductive layer electrically connected to the third conductive part,
The contact portion is
The second conductive portion, the third conductive portion, and a conductive layer electrically connected to the second conductive portion and the third conductive portion,
The conductive layer of the first monitor unit is longer than the conductive layer of the contact unit.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

1. Semiconductor Device (1) First, the semiconductor device according to the present embodiment that is an object of inspection will be described. FIG. 1 is a cross-sectional view schematically showing a semiconductor device 1000 according to this embodiment. FIG. 2 is a plan view schematically showing the semiconductor device 1000 according to the present embodiment. 1 is a cross-sectional view taken along line AA shown in FIG. In FIG. 2, illustrations other than the first monitor 100 are omitted.

  As shown in FIG. 1, the semiconductor device 1000 includes a semiconductor substrate 10, an insulating film 20, a first conductive part 50, a first insulating film 30, a second conductive part 60, a second insulating film 40, And a third conductive portion 70.

  The semiconductor substrate 10 is made of a first conductivity type (for example, P type) silicon substrate.

  The insulating film 20 is formed on the semiconductor substrate 10. The insulating film 20 is made of, for example, silicon dioxide. The insulating film 20 may be an interlayer insulating film or an element isolation insulating film (for example, a LOCOS (Local Oxidation of Silicon) layer, a semi-recessed LOCOS layer, a trench insulating layer).

  The first conductive unit 50 is formed on the insulating film 20. The first conductive portion 50 is made of, for example, a metal including at least one of aluminum and copper, or polysilicon.

  The first insulating film 30 is formed on the first conductive portion 50 and the insulating film 20. The first insulating film 30 is made of, for example, silicon dioxide. The first insulating film 30 is, for example, an interlayer insulating film.

  The second conductive part 60 is formed on the first insulating film 30. The second conductive portion 60 is made of a metal including at least one of aluminum and copper, for example.

  The second insulating film 40 is formed on the second conductive portion 60 and the first insulating film 30. The second insulating film 40 is made of, for example, silicon dioxide. The second insulating film 40 is, for example, an interlayer insulating film.

  The third conductive portion 70 is formed on the second insulating film 40. The third conductive portion 70 is made of a metal including at least one of aluminum and copper, for example.

  As shown in FIG. 1, the semiconductor device 1000 includes a contact unit 200, a first monitor unit 100, a second monitor unit 120, a third monitor unit 140, a fourth monitor unit 160, and a fifth monitor unit 180. And having.

  The contact part 200 is formed in the contact part formation region 200a. The contact part 200 is formed in the second conductive part 60, the third conductive part 70, and the contact hole 84 of the second insulating film 40, and is electrically connected to the second conductive part 60 and the third conductive part 70. And a conductive layer 94. It can be said that the conductive layer 94 of the contact part 200 is a plug that electrically connects the second conductive part 60 and the third conductive part 70.

  The contact part 200 is a part of an IC circuit, for example.

  The first monitor unit 100 is formed in the first monitor unit formation region 100a. The first monitor unit 100 includes a first conductive unit 50, a third conductive unit 70, a conductive layer 90 formed in the recess 80 of the second insulating film 40 and electrically connected to the third conductive unit 70, including.

  The conductive layer 90 of the first monitor unit 100 is longer than the conductive layer 94 of the contact unit 200 in the thickness direction (Y direction) of the second insulating film 40. That is, the depth 80y of the recess 80 where the conductive layer 90 of the first monitor unit 100 is formed is deeper than the depth 84y of the contact hole 84 where the conductive layer 94 of the contact unit 200 is formed. Further, the width of the conductive layer 90 of the first monitor unit 100 is, for example, the same as the width of the conductive layer 94 of the contact unit 200. That is, the hole diameter 80x of the recess 80 where the conductive layer 90 of the first monitor unit 100 is formed is the same as the hole diameter 84x of the contact hole 84 where the conductive layer 94 of the contact part 200 is formed. A plurality of conductive layers 90 are provided as shown in FIG. Although nine conductive layers 90 are provided in FIG. 2, the number is not particularly limited.

  Although not illustrated, the recess 80 may reach the first insulating film 30. However, the concave portion 80 does not reach the first conductive portion 50.

  The first conductive unit 50 of the first monitor unit 100 includes a pad unit 50a as shown in FIG. Similarly, the third conductive unit 70 of the first monitor unit 100 includes a pad unit 70a. Although not shown, the conductive portions 50, 60, and 70 of each monitor portion can also have a pad portion.

The first monitor unit 100 can measure the capacitance C ₁₀₀ by applying a voltage to the first conductive unit 50 and the third conductive unit 70. Details will be described later.

As shown in FIG. 1, the second monitor unit 120 is formed in the second monitor unit formation region 120a. The second monitor unit 120 includes a first conductive unit 50 and a third conductive unit 70. The second monitor unit 120 can measure the capacitance C ₁₂₀ by applying a voltage to the first conductive unit 50 and the third conductive unit 70.

  The third monitor unit 140 is formed in the third monitor unit formation region 140a. The third monitor unit 140 includes a first conductive unit 50, a third conductive unit 70, a conductive layer 92 formed in the recess 82 of the second insulating film 40 and electrically connected to the third conductive unit 70, including.

  The hole diameter 82x of the recess 82 in which the conductive layer 92 of the third monitor unit 140 is formed is equal to the hole diameter 80x of the recess 80 in which the conductive layer 90 of the first monitor unit 100 is formed, and the conductive layer of the contact unit 200. 94 is larger than the hole diameter 84x of the contact hole 84 in which the hole 94 is formed. In addition, the depth 82y of the recess 82 in which the conductive layer 92 of the third monitor unit 140 is formed is deeper than the depth 84y of the contact hole 84 in which the conductive layer 94 of the contact unit 200 is formed. Although not shown, the recess 82 may reach the first insulating film 30. However, the concave portion 82 does not reach the first conductive portion 50.

  Although not shown, the third conductive portion 70 may not be formed in the recess 82, and only the conductive layer 92 may be formed. In addition, the conductive layer 92 may not be formed in the concave portion 82, and only the third conductive portion 70 may be formed.

The third monitor unit 140 can measure the capacitance C ₁₄₀ by applying a voltage to the first conductive unit 50 and the third conductive unit 70.

The fourth monitor unit 160 is formed in the fourth monitor unit formation region 160a. The fourth monitor unit 160 includes a first conductive unit 50 and a second conductive unit 60. The fourth monitor unit 160 can measure the capacitance C ₁₆₀ by applying a voltage to the first conductive unit 50 and the second conductive unit 60.

The fifth monitor unit 180 is formed in the fifth monitor unit formation region 180a. The fifth monitor unit 180 includes a second conductive unit 60 and a third conductive unit 70. The fifth monitor unit 180 can measure the capacitance C ₁₈₀ by applying a voltage to the second conductive unit 60 and the third conductive unit 70.

  (2) Next, a method for manufacturing a semiconductor device to be inspected will be described. 3 and 4 are cross-sectional views schematically showing the manufacturing process of the semiconductor device 1000 according to the present embodiment.

  As shown in FIG. 3, the insulating film 20 is formed on the semiconductor substrate 10, the first conductive part 50 is formed on the insulating film 20, and the first insulating film 30 is formed on the first conductive part 50 and the insulating film 20. The second conductive part 60 is formed on the first insulating film 30, and the second insulating film 40 is formed on the second conductive part 60 and the first insulating film 30. The insulating films 20, 30, and 40 are formed by, for example, a CVD (Chemical Vapor Deposition) method. The conductive portions 50 and 60 are formed by, for example, a CVD method, a sputtering method, or a plating method.

  As shown in FIG. 3, the second insulating film 40 is etched to form a contact hole 84 and a recess 80 in the contact portion forming region 200a, the first monitor portion forming region 100a, and the third monitor portion forming region 140a. , 82 are formed simultaneously. Etching is performed, for example, using a resist layer (not shown) as a mask. In the etching, even if the thickness of the second conductive layer 60 in the contact portion formation region 200a or the thickness of the second insulating film 40 varies, the surface of the second conductive portion 60 is exposed by forming the contact hole 84. Over-etching is performed so that Here, since the second conductive layer 60 is not formed in the first monitor portion formation region 100a and the third monitor portion formation region 140a, the second insulating film 40 is further etched by overetching, and the recesses 80, 82 extends in the -Y direction. Therefore, the depths 80 y and 82 y of the recesses 80 and 82 depend on the amount of overetching for forming the contact hole 84. That is, the depths 80y and 82y of the recesses 80 and 82 are deeper than the depth 84y of the contact hole.

  As shown in FIG. 4, conductive layers 94, 90, and 92 are formed in the contact hole 84 and the recesses 80 and 82, respectively. That is, the lengths of the conductive layers 90 and 92 depend on the amount of overetching for forming the contact hole 84. Specifically, as a manufacturing method of the conductive layers 94, 90, 92, first, for example, a tungsten layer (not shown) is formed on the second insulating film 40 so as to fill the contact hole 84 and the recesses 80, 82. . The tungsten layer is formed by sputtering, for example. Next, the tungsten layer is removed until the upper surface of the tungsten layer in the contact hole 84 and the recesses 80 and 82 is substantially the same as the upper surface of the second insulating film 40. The removal of the tungsten layer is performed by, for example, a CMP (Chemical Mechanical Polish) method. In this way, conductive layers 94, 90, and 92 are formed. At this time, since the recess 82 of the third monitor portion formation region 140a has a large opening (because the hole diameter 82x is large), the conductive layer 92 formed in the recess 82 is almost removed, for example. Become.

  As shown in FIG. 1, the third conductive portion 70 is formed on the conductive layers 94, 90, 92 and the second insulating film 40. The third conductive portion 70 is formed by, for example, a CVD method, a sputtering method, or a plating method.

  Through the above steps, the semiconductor device 1000 can be manufactured.

  (3) Next, a semiconductor device according to a modified example of the present embodiment, which is an inspection target, will be described. FIG. 5 is a cross-sectional view schematically showing a semiconductor device 2000 according to a modification of the present embodiment. Hereinafter, in the semiconductor device 2000, members having the same functions as the constituent members of the semiconductor device 1000 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the semiconductor device 2000, as shown in FIG. 5, the first conductive portion 52 is formed of a second conductivity type (for example, N type) impurity region formed in the semiconductor substrate 10. The first conductive portion 52 is formed by implanting N-type impurities into the semiconductor substrate 10 using a resist layer (not shown) as a mask.

  In the semiconductor device 2000, the first insulating film 32 is an element isolation insulating film, and the second conductive portion 62 is made of a polysilicon layer.

2. Semiconductor Device Inspection Method Next, a semiconductor device inspection method will be described. In the present embodiment, the above-described semiconductor device 1000 can be inspected. FIG. 6 is a view for explaining the inspection method of the semiconductor device 1000 according to the present embodiment.

  (1) First, as shown in FIG. 6, a semiconductor device 1000 having a conductive portion sandwiching an insulating film is prepared (S1). The semiconductor device 1000 can be manufactured by the manufacturing method described above.

  (2) Next, as shown in FIG. 6, a voltage is applied to the conductive portion, and the capacitance of the insulating film is measured (S2). The voltage can be applied by bringing the probe into contact with the pad portions of the conductive portions 50, 60, and 70 of the monitor portions described above.

As shown in FIG. 1, the first monitor unit 100 can measure the capacitance C ₁₀₀ of the first monitor unit 100 by applying a voltage to the first conductive unit 50 and the third conductive unit 70. Capacitance _{C 100} of the first monitoring section 100, a capacitance _{C 102} of the insulating film 30 and 40 between the first conductive portion 50 and the conductive layer 90, the first conductive portion 50 between the third conductive portion 70 And a capacitor C ₁₀₄ of the insulating films 30 and 40.

The second monitor unit 120 can measure the capacitance C ₁₂₀ of the second monitor unit 120 by applying a voltage to the first conductive unit 50 and the third conductive unit 70. Capacitance _{C 120} of the second monitoring portion 120 is a capacitive insulating film 30 and 40 between the first conductive portion 50 and the third conductive portion 70.

The third monitor unit 140 can measure the capacitance C ₁₄₀ of the third monitor unit 140 by applying a voltage to the first conductive unit 50 and the third conductive unit 70. The third capacitance _{C 140} of the monitor unit 140, the capacitance _{C 142} of the insulating film 30 and 40 between the first conductive portion 50 and the conductive layer 92 and third conductive section 70, the first conductive portion 50 third conductive And a capacitance C ₁₄₄ of the insulating films 30 and 40 between the portion 70.

The fourth monitor unit 160 can measure the capacitance C ₁₆₀ of the fourth monitor unit 160 by applying a voltage to the first conductive unit 50 and the second conductive unit 60. Capacitance _{C 160} of the fourth monitor 160 is the capacitance of the first insulating film 30 between the first conductive portion 50 and the second conductive portion 60.

The fifth monitor unit 180 can measure the capacitance C ₁₈₀ of the fifth monitor unit 180 by applying a voltage to the second conductive unit 60 and the third conductive unit 70. Capacitance _{C 180} of the fifth monitor 180 is the capacitance of the second insulating film 40 between the second conductive portion 60 and the third conductive portion 70.

  (3) Next, as shown in FIG. 6, the film thickness of the insulating film is inspected based on the measured capacity of the insulating film (capacity of each monitor unit) (S3). As shown in the following formula (1), the thickness (film thickness) d of the insulating film depends on the capacitance C of the insulating film. In the following formula (1), ε is the dielectric constant of the insulating film, and S is the area of the conductive portion and the conductive layer sandwiching the insulating film.

            C = ε × S / d (1)

(3-1) Capacity _{C 100} of the first monitoring portion 100, as shown in FIG. 1 includes a capacitor _{C 102} of the insulating film 30 and 40 between the first conductive portion 50 and the conductive layer 90. Therefore, the film thickness of the insulating films 30 and 40 between the first conductive unit 50 and the conductive layer 90 of the first monitor unit 100 can be inspected based on the capacitance C ₁₀₀ of the first monitor unit 100. Further, as described above, the length of the conductive layer 90 (the depth 80y of the recess 80) depends on the amount of overetching for forming the contact hole 84. That is, the thickness of the insulating films 30 and 40 between the first conductive portion 50 and the conductive layer 90 depends on the amount of overetching for forming the contact hole 84. Therefore, the first monitor unit 100 can inspect the amount of overetching for forming the contact hole 84.

More specifically, for example, in the step of measuring the electrical characteristics of the semiconductor manufacturing process, the capacitance C ₁₀₀ of the first monitor unit 100 is measured every time or by sampling. Then, the standard value of the capacity C ₁₀₀ is set in advance in consideration of the average value, error, and the like of the capacity C ₁₀₀ of the plurality of first monitor units 100. Then, the overetching amount for forming the contact hole 84 can be relatively inspected by comparing the standard value of the capacitance C ₁₀₀ with the measured capacitance C ₁₀₀ . That is, when the measured capacitance C ₁₀₀ is out of the standard value, it can be seen that the failure of the over-etching for forming the contact hole 84 occurs.

If the measured capacitance C ₁₀₀ is larger than the standard value, because the thickness of the insulating film 30, 40 between the first conductive portion from the equation (1) 50 and the conductive layer 90 is small, it overetching amount is large I understand. In this case, an etching product may be generated on the surface of the second conductive part 60 of the second contact part 200. Etching products can cause poor electrical properties. If the measured capacitance C ₁₀₀ is smaller than the standard value, because the thickness of the insulating film 30, 40 between the first conductive portion from the equation (1) 50 and the conductive layer 90 is large, it overetching amount is small I understand. In this case, the second conductive part 60 of the second contact part 200 and the conductive layer 94 may not be electrically connected.

  As described above, the first monitor unit 100 can electrically inspect the overetching amount for forming the contact hole 84, so that the manufacturing process can be easily managed, and the cause of the defect Identification can be performed quickly and easily.

(3-2) Based on the capacitance C ₁₂₀ of the second monitor unit 120, the film thickness of the insulating films 30 and 40 between the first conductive unit 50 and the third conductive unit 70 of the second monitor unit 120 is inspected. be able to. As described above, the capacitance _{C 100} of the first monitoring section 100, a capacitance _{C 102} of the insulating film 30 and 40 between the first conductive portion 50 and the conductive layer 90, the first conductive portion 50 third conductive portion 70 And the capacitance C ₁₀₄ of the insulating films 30 and 40 between them. Here, the capacitor C ₁₀₄ is a capacitor that does not depend on the amount of overetching for forming the contact hole 84. Therefore, the first monitoring portion 100, to check the amount of over-etching for forming the contact hole 84, the capacitance _{C 100} of the first monitoring portion 100, Sappii capacitance _{C 104} that is independent of the amount of overetching More preferably, it is performed based on the capacity (that is, capacity C ₁₀₂ ).

Here, the capacitor C ₁₀₄ and the capacitor C ₁₂₀ of the second monitor unit 120 are capacitors having the same film thickness as shown in FIG. Therefore, by performing the area in terms of the first conductive film 50 and the third conductive film 70 for capacitor _{C 120,} it is possible to Sappiku capacitance _{C 104} from the capacitance _{C 100} of the first monitoring portion 100. That is, the capacitances of the insulating films 30 and 40 between the first conductive unit 50 and the conductive layer 90 depending on the overetching amount for forming the contact hole 84 by the first monitor unit 100 and the second monitor unit 200. C ₁₀₂ can be calculated. That is, since the insulating films 30 and 40 between the first conductive unit 50 and the conductive layer 90 of the first monitor unit 100 can be inspected more accurately, the overetching amount for forming the contact hole 84 more accurately. Can be inspected.

(3-3) Capacity _{C 140} of the third monitoring portion 140 includes a capacitance _{C 142} of the insulating film 30 and 40 between the first conductive portion 50 and the conductive layer 90. Therefore, the films of the insulating films 30 and 40 between the first conductive part 50 and the conductive layer 90 that depend on the amount of overetching for forming the contact hole 84 based on the capacitance C ₁₄₀ of the third monitor part 140. Thickness can be inspected.

Here, as described above, the hole diameter 82x of the recess 82 in which the conductive layer 92 and the third conductive portion 70 of the third monitor unit 140 are formed is the recess in which the conductive layer 90 of the first monitor 180 is formed. 80 hole diameter is larger than 80x. Therefore, the recess 82 is less susceptible to the variation in the hole diameter 84 x of the contact hole 84 than the recess 80. That is, in the first monitor unit 100 alone, for example, since the hole diameter 80x of the recess 80 is the same as the hole diameter 84x of the contact hole 84, the hole diameter 80x of the recess 80 varies when the hole diameter 84x of the contact hole 84 varies. become. Then, the capacitance C ₁₀₀ of the first monitoring portion 100 measured, when not deviate from a preset standard value, the cause, whether to rely on the over-etching amount to form the contact 84, the contact hole 84 There may be a problem that it is difficult to determine whether or not it depends on variations in the hole diameter 84x.

  With respect to such a problem, the third monitor 140 is not easily affected by variations in the hole diameter 84x of the contact hole 84 because the hole diameter 82x of the recess 82 is large. In particular, the first monitor 100 and the fifth monitor 180 are not affected. Thus, the amount of overetching for forming the contact hole 84 can be inspected more accurately.

Similar to the first monitor unit 100, the third monitor unit 140 differs from the capacitor C ₁₄₀ of the third monitor unit 140 by the capacitor C ₁₂₀ of the second monitor unit to a capacitance C ₁₄₄ that does not depend on the overetching amount. Can be drawn.

(3-4) Based on the capacitance C ₁₆₀ of the fourth monitor unit 160, the film thickness of the first insulating film 30 between the first conductive unit 50 and the second conductive unit 60 can be inspected. Further, the film thickness of the second insulating film 40 between the second conductive unit 60 and the third conductive unit 70 can be inspected based on the capacitance C ₁₈₀ of the fifth monitor unit 180. Specifically, it similarly to the capacitance _{C 100} of the first monitoring portion 100, previously sets the standard value for the capacitance _{C 160, C 180,} compares the standard value, the capacitor _{C 160, C 180} was measured, the Thus, the film thicknesses of the insulating films 30 and 40 can be relatively inspected. That is, since the film thickness of the insulating films 30 and 40 can be electrically inspected by the fourth monitor unit 160 and the fifth monitor unit 180, the manufacturing process can be easily managed, and the cause of the defect Can be identified quickly and easily.

  The semiconductor device inspection method according to the present embodiment has the following features, for example.

  In the semiconductor device inspection method according to the present embodiment, the film thickness of the insulating film can be inspected based on the capacitance of the insulating film. That is, since the thickness of the insulating film can be electrically inspected, the manufacturing process can be easily managed, and the cause of the defect can be identified quickly and easily.

In the semiconductor device inspection method according to the present embodiment, in the first monitor unit 100, a voltage is applied to the first conductive unit 50 and the third conductive unit 70 to measure the capacitance C ₁₀₀ of the first monitor unit 100. be able to. Based on the capacitance C ₁₀₀ of the first monitor unit 100, the film thickness of the insulating films 30 and 40 between the first conductive unit 50 and the conductive layer 90 of the first monitor unit 100 can be inspected. The film thickness of the insulating films 30 and 40 between the first conductive part 50 and the conductive layer 90 depends on the amount of overetching for forming the contact hole 84. Therefore, it is possible to inspect the amount of overetching for forming the contact hole 84 by the first monitor unit.

In the semiconductor device inspection method according to the present embodiment, a plurality of conductive layers 90 of the first monitor unit 100 can be provided. Therefore, for example, even if the shape of one conductive layer 90 is defective, the shape of the other conductive layer 90 is normal, and the variation in the capacitance C ₁₀₀ of the first monitor unit 100 due to the defective shape of the conductive layer 90 is caused. Can be small.

  In the semiconductor device inspection method according to the present embodiment, the width of the conductive layer 90 of the first monitor unit 100 may be the same as the width of the conductive layer 94 of the contact unit 200. That is, the hole diameter 80x of the recess 80 where the conductive layer 90 of the first monitor unit 100 is formed is the same as the hole diameter 84x of the contact hole 84 where the conductive layer 94 of the contact part 200 is formed. Therefore, since the microloading effect when forming the recess 80 and the contact hole 84 is generated in the same manner with respect to the recess 80 and the contact hole 84, the etching rate can be made the same. For this reason, the first monitor unit 100 can inspect the overetching amount for forming the contact hole 84 more accurately.

In the semiconductor device inspection method according to the present embodiment, in the second monitor unit 120, a voltage is applied to the first conductive unit 50 and the third conductive unit 70 to measure the capacitance C ₁₂₀ of the second monitor unit 120. be able to. Here, the capacitance C ₁₀₄ that does not depend on the over-etching amount of the first monitor unit 100 and the capacitance C ₁₂₀ of the second monitor unit 120 have the same film thickness. Therefore, by performing the area in terms of the first conductive film 50 and the third conductive film 70 for capacitor _{C 120,} it is possible to Sappiku capacitance _{C 104} from the capacitance _{C 100} of the first monitoring portion 100. That is, the capacitances of the insulating films 30 and 40 between the first conductive unit 50 and the conductive layer 90 depending on the overetching amount for forming the contact hole 84 by the first monitor unit 100 and the second monitor unit 200. C ₁₀₂ can be calculated. That is, since the insulating films 30 and 40 between the first conductive unit 50 and the conductive layer 90 of the first monitor unit 100 can be inspected more accurately, the overetching amount for forming the contact hole 84 more accurately. Can be inspected.

In the semiconductor device inspection method according to the present embodiment, the third monitor unit 140 applies a voltage to the first conductive unit 50 and the third conductive unit 70 to measure the capacitance C ₁₄₀ of the third monitor unit 140. be able to. Here, the hole diameter 82x of the concave portion 82 in which the conductive layer 92 and the third conductive portion 70 of the third monitor unit 140 are formed is equal to the hole diameter 80x of the concave portion 80 in which the conductive layer 90 of the first monitor 180 is formed. Greater than. Therefore, as described above, the concave portion 82 is not easily affected by the variation in the hole diameter 84x of the contact hole 84. In particular, the first monitor 100 and the fifth monitor 180 provide a more accurate contact hole of the contact portion 200. The amount of overetching for forming 84 can be inspected.

  Note that the above-described contents can be applied to the inspection method of the semiconductor device 2000 which is a modified example of the inspection target according to the present embodiment. Therefore, the description is omitted.

3. Semiconductor Device Manufacturing Method The semiconductor device inspection method described above can be applied to the semiconductor device manufacturing method according to the present embodiment. Therefore, the description is omitted.

  Although the embodiments of the present invention have been described in detail as described above, those skilled in the art will readily understand that many modifications are possible without substantially departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention.

FIG. 3 is a cross-sectional view schematically showing the semiconductor device according to the embodiment. FIG. 3 is a plan view schematically showing the semiconductor device according to the embodiment. Sectional drawing which shows typically the manufacturing process of the semiconductor device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the semiconductor device which concerns on this embodiment. Sectional drawing which shows typically the semiconductor device which concerns on the modification of this embodiment. 5 is a flowchart schematically showing a semiconductor device inspection method according to the embodiment.

Explanation of symbols

10 semiconductor substrate, 20 insulating film, 30 first insulating film, 32 first insulating film,
40 second insulating film, 50 first conductive portion, 50a pad portion, 52 first conductive portion,
60 second conductive portion, 62 second conductive portion, 70 third conductive portion, 70a pad portion,
80 recesses, 82 recesses, 84 contact holes, 90 conductive layers, 92 conductive layers,
94 conductive layer, 100 first monitor portion, 100a first monitor portion formation region,
120 2nd monitor part, 120a 2nd monitor part formation area, 140 3rd monitor part,
140a 3rd monitor part formation area, 160 4th monitor part,
160a 4th monitor part formation area, 180 5th monitor part,
180a 5th monitor part formation area, 200 contact part,
200a Contact part formation region, 1000 semiconductor device, 2000 semiconductor device

Claims (14)

Preparing a semiconductor device having a conductive portion sandwiching an insulating film;
Applying a voltage to the conductive portion to measure the capacitance of the insulating film;
Inspecting the thickness of the insulating film based on the capacity of the insulating film;
A method for inspecting a semiconductor device, comprising: In claim 1,
The semiconductor device includes:
A first conductive part;
A first insulating film formed above the first conductive portion;
A second conductive portion formed above the first insulating film;
A second insulating film formed above the second conductive portion;
A third conductive portion formed above the second insulating film;
Including
The semiconductor device includes:
The first conductive portion;
The third conductive portion;
A conductive layer formed in a recess of the second insulating film and electrically connected to the third conductive portion;
A first monitor unit having
The step of measuring the capacity of the insulating film includes:
Measuring the capacitance by applying a voltage to the first conductive portion and the third conductive portion of the first monitor portion;
The step of inspecting the film thickness of the insulating film includes:
A method for inspecting a semiconductor device, comprising: inspecting a film thickness of an insulating film between the first conductive portion and the conductive layer of the first monitor portion based on a capacitance of the first monitor portion. In claim 2,
The semiconductor device includes:
The second conductive portion;
The third conductive portion;
A conductive layer formed in a contact hole of the second insulating film and electrically connected to the second conductive portion and the third conductive portion;
Including a contact portion having
The conductive layer of the first monitor unit is longer than the conductive layer of the contact unit,
A method for inspecting a semiconductor device, wherein an over-etching amount for forming the contact hole is inspected by inspecting a film thickness of an insulating film between the first conductive portion and the conductive layer of the first monitor portion . In claim 2 or 3,
A method for inspecting a semiconductor device, wherein a plurality of the conductive layers of the first monitor unit are provided. In any of claims 2 to 4,
The method for inspecting a semiconductor device, wherein a width of the conductive layer of the first monitor unit is the same as a width of the conductive layer of the contact unit. In any of claims 2 to 5,
The semiconductor device includes:
A second monitor unit having the first conductive unit and the third conductive unit;
The step of measuring the capacity of the insulating film includes:
Furthermore, the capacitance is measured by applying a voltage to the first conductive portion and the third conductive portion of the second monitor portion,
The step of inspecting the film thickness of the insulating film includes:
Inspecting the film thickness of the insulating film between the first conductive portion and the conductive layer of the first monitor portion based on the capacitance of the first monitor portion and the capacitance of the second monitor portion. Inspection method of semiconductor device. In any of claims 3 to 6,
The semiconductor device includes:
The first conductive portion;
The third conductive portion;
A conductive layer formed in a recess of the second insulating film and electrically connected to the third conductive portion;
A third monitor unit having
The hole diameter of the recess in which the conductive layer of the third monitor unit is formed is larger than the hole diameter of the recess in which the conductive layer of the first monitor unit is formed,
The step of measuring the capacity of the insulating film includes:
Furthermore, the capacitance is measured by applying a voltage to the first conductive part and the third conductive part of the third monitor part,
The step of inspecting the film thickness of the insulating film includes:
Further, based on the capacitance of the third monitor unit, inspect the film thickness of the insulating film between the first conductive unit and the conductive layer of the third monitor unit,
The film thickness of the insulating film between the first conductive part and the conductive layer of the first monitor part, and the film thickness of the insulating film between the first conductive part and the conductive layer of the third monitor part. And inspecting the amount of over-etching for forming the contact hole. In any of claims 3 to 6,
The semiconductor device includes:
The first conductive portion;
The third conductive portion formed in the recess of the second insulating film;
A third monitor unit having
The hole diameter of the concave portion in which the third conductive portion of the third monitor portion is formed is larger than the hole diameter of the concave portion in which the conductive layer of the first monitor portion is formed,
The step of measuring the capacity of the insulating film includes:
Furthermore, the capacitance is measured by applying a voltage to the first conductive part and the third conductive part of the third monitor part,
The step of inspecting the film thickness of the insulating film includes:
Further, based on the capacitance of the third monitor unit, inspect the film thickness of the insulating film between the first conductive unit and the conductive layer of the third monitor unit,
The film thickness of the insulating film between the first conductive part and the conductive layer of the first monitor part, and the film thickness of the insulating film between the first conductive part and the conductive layer of the third monitor part. And inspecting the amount of over-etching for forming the contact hole. In any of claims 2 to 8,
The semiconductor device includes:
A fourth monitor unit having the first conductive unit and the second conductive unit;
The step of measuring the capacity of the insulating film includes:
Measuring a capacitance by applying a voltage to the first conductive portion and the second conductive portion of the fourth monitor portion;
The step of inspecting the film thickness of the insulating film includes:
A method for inspecting a semiconductor device, comprising: inspecting a film thickness of an insulating film between the first conductive part and the second conductive part of the fourth monitor unit based on a capacitance of the fourth monitor unit. In any of claims 2 to 9,
The semiconductor device includes:
A fifth monitor unit having the second conductive unit and the third conductive unit;
The step of measuring the capacity of the insulating film includes:
Measuring the capacitance by applying a voltage to the second conductive portion and the third conductive portion of the fifth monitor portion;
The step of inspecting the film thickness of the insulating film includes:
A method for inspecting a semiconductor device, comprising: inspecting a film thickness of an insulating film between the second conductive portion and the third conductive portion of the fifth monitor portion based on a capacitance of the fifth monitor portion. In any of claims 2 to 10,
The first conductive part is made of metal or polysilicon,
The semiconductor device inspection method, wherein the second conductive portion and the third conductive portion are made of metal. In any of claims 2 to 10,
The first conductive portion comprises an impurity region formed in a semiconductor substrate,
The second conductive part is made of polysilicon,
The method for inspecting a semiconductor device, wherein the third conductive portion is made of metal. Preparing a semiconductor device having a conductive portion sandwiching an insulating film;
Applying a voltage to the conductive portion to measure the capacitance of the insulating film;
Inspecting the thickness of the insulating film based on the capacity of the insulating film;
A method for manufacturing a semiconductor device, comprising: A semiconductor device including a monitor unit and a contact unit,
The semiconductor device includes:
A first conductive part;
A first insulating film formed above the first conductive portion;
A second conductive portion formed above the first insulating film;
A second insulating film formed above the second conductive portion;
A third conductive portion formed above the second insulating film;
Including
The monitor unit is
The first conductive part, the third conductive part, and a conductive layer electrically connected to the third conductive part,
The contact portion is
The second conductive portion, the third conductive portion, and a conductive layer electrically connected to the second conductive portion and the third conductive portion,
The semiconductor device in which the conductive layer of the first monitor unit is longer than the conductive layer of the contact unit.

Images