TWI847479B - Overlay measurement element and operating method thereof - Google Patents

Abstract

An operating method of an overlay measurement element includes measuring a first charge current flowing through a first section of a second conductive layer located on a first conductive layer, the first conductive layer, and a second section of the second conductive layer, in which the first conductive layer is located in a first insulated layer, the second conductive layer is located in a second insulated layer, and a bottom surface of the first section is in contact with the first conductive layer and a first portion of the first insulated layer; measuring a second charge current flowing through a third section of the second conductive layer, the first conductive layer and a forth section of the second conductive layer, in which a bottom surface of the forth section is in contact with the first conductive layer and a second portion of the first insulated layer, the first portion and the second portion of the first insulated layer are respectively located on opposite sides of the first conductive layer; and comparing the first charge current and the second charge current to determine whether a center line of the first conductive layer overlaps with a symmetry line of the second conductive layer.

Description

Stacked measuring element and operation method thereof

The present disclosure relates to a stacked measurement element and an operating method of the stacked measurement element.

Generally speaking, the internal circuit of an integrated circuit chip includes various semiconductor components, such as diodes, transistors, capacitors and other components. The semiconductor components are interconnected through the process to produce different chips. In the chip manufacturing process, the overlay shift between the stacking layers will affect the wafer yield, so the overlay measurement performed on the wafer is very important.

Current overlay metrology usually uses light or electron beam as the measurement signal, including image-based overlay (IBO) measurement, diffraction-based overlay (DBO) measurement, and in-die overlay measurement that requires the use of a critical dimension scanning electron microscope (CD-SEM).

One technical aspect of the present disclosure is an operating method of a stacked measurement element.

According to some embodiments of the present disclosure, a method for operating a stacked measuring element includes measuring a first current passing through a first section of a second conductive layer on a first conductive layer, and a second section of the first conductive layer and the second conductive layer, wherein the first conductive layer is located in a first insulating layer, the second conductive layer is located in the second insulating layer, and a bottom surface of the first section contacts the first conductive layer and a first portion of the first insulating layer; measuring A second current passes through the third section of the second conductive layer, the first conductive layer, and the fourth section of the second conductive layer, wherein the bottom surface of the fourth section contacts the first conductive layer and the second portion of the first insulating layer, and the first portion and the second portion of the first insulating layer are respectively located at opposite sides of the first conductive layer; the first current is compared with the second current to determine whether the center line of the first conductive layer and the symmetry line of the second conductive layer overlap.

In some implementations, the method for operating the stacked measurement element further includes overlapping a center line of the first conductive layer and a symmetric line of the second conductive layer when the first current is equal to the second current.

In some embodiments, when the center line of the first conductive layer overlaps with the symmetry line of the second conductive layer, a first contact area between the first segment of the second conductive layer and the first conductive layer is equal to a second contact area between the fourth segment of the second conductive layer and the first conductive layer.

In some implementations, the operating method of the stacked measurement element further includes that when the first current is greater than the second current, the symmetry lines of the second conductive layer are separated by a distance on the right side of the center line of the first conductive layer.

In some embodiments, when the symmetry lines of the second conductive layer are separated by a distance to the right of the center line of the first conductive layer, a first contact area between the first segment of the second conductive layer and the first conductive layer is larger than a second contact area between the fourth segment of the second conductive layer and the first conductive layer.

In some implementations, the operating method of the stacked measurement element further includes that when the first current is less than the second current, the symmetry lines of the second conductive layer are separated by a distance on the left side of the center line of the first conductive layer.

In some embodiments, when the symmetry lines of the second conductive layer are separated by a distance to the left of the center line of the first conductive layer, a first contact area between the first segment of the second conductive layer and the first conductive layer is smaller than a second contact area between the fourth segment of the second conductive layer and the first conductive layer.

In some embodiments, the operating method of the stacked measuring element further includes applying a bias to the first segment and the second segment of the second conductive layer when measuring a first current passing through a first segment of the second conductive layer on the first conductive layer, and the first conductive layer and the second segment of the second conductive layer; and applying the above-mentioned bias to the fourth segment and the third segment of the second conductive layer when measuring a second current passing through a third segment of the second conductive layer, and the first conductive layer and the fourth segment of the second conductive layer.

Another technical aspect of the present disclosure is a stacked measurement element.

According to some embodiments of the present disclosure, a stacked measurement element includes a semiconductor substrate, a first conductive layer, a first insulating layer, a second conductive layer and a second insulating layer. The semiconductor substrate has a cutting path. The first conductive layer is located on the cutting path of the semiconductor substrate. The first insulating layer is located on the cutting path of the semiconductor substrate. The first insulating layer surrounds the first conductive layer and has a first portion and a second portion respectively on opposite sides of the first conductive layer. The second conductive layer is located on the first conductive layer and has a first section, a second section, a third section and a fourth section in sequence. The bottom surface of the first section contacts the first conductive layer and the first portion of the first insulating layer. The bottom surface of the fourth segment contacts the first conductive layer and the second portion of the first insulating layer. The first segment, the second segment, the third segment and the fourth segment have a symmetry line, and the first segment and the second segment are symmetric with the fourth segment and the third segment respectively along the symmetry line. Each of the first segment, the second segment, the third segment and the fourth segment has the same bottom area. The second insulating layer is located on the first conductive layer and the first insulating layer, and surrounds the second conductive layer.

In some embodiments, the first segment and the second segment and the third segment and the fourth segment of the second conductive layer have the same first distance, and the second conductive layer further has a plurality of fifth segments, the fifth segment is located between the second segment and the third segment, and the distance between two adjacent fifth segments is the first distance or a second distance different from the first distance.

In some embodiments, each of the first segment, the second segment, the third segment, and the fourth segment of the second conductive layer has a plurality of separated parts, the distance between two adjacent parts is the same, and the top view shape of the parts is rectangular or circular.

In the above-mentioned embodiments of the present disclosure, since the operation method of the overlay measurement element includes comparing the first current and the second current to determine whether the center line of the first conductive layer and the symmetry line of the second conductive layer overlap, the overlay measurement using the above-mentioned operation method is based on the electrical properties of the overlay measurement element, rather than using light or electron beam as the measurement signal. Different from the traditional image-based overlay (IBO) measurement, the diffraction-based overlay (DBO) measurement and the in-die overlay measurement that requires the use of a critical dimension scanning electron microscope (CD-SEM), the overlay measurement is not limited by the light or electron beam signal.

The embodiments disclosed below provide many different embodiments, or examples, for implementing the different features of the subject matter provided. Specific examples of components and arrangements are described below to simplify the present invention. Of course, these examples are only examples and are not intended to be limiting. In addition, the present invention may repeat component symbols and/or letters in each example. This repetition is for the purpose of simplicity and clarity, and does not itself specify the relationship between the various embodiments and/or configurations discussed.

Spatially relative terms such as "below," "beneath," "lower," "above," "upper," and the like may be used herein for descriptive purposes to describe the relationship of one element or feature to another element or feature as illustrated in the accompanying figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

FIG. 1 is a flow chart showing an operation method of a stacked measurement element according to an embodiment of the present disclosure. FIG. 2 to FIG. 4 are cross-sectional views of the stacked measurement element 100 under different circumstances according to the operation method of the stacked measurement element 100 according to an embodiment of the present disclosure. Referring to FIG. 1 and FIG. 2 simultaneously, the operation method of the stacked measurement element (e.g., the stacked measurement element 100 of FIG. 2) includes the following process. In step S1, a first current I1 is measured through a first section 141 of a second conductive layer 140 on a first conductive layer 120, the first conductive layer 120, and a second section 142 of the second conductive layer 140. The first conductive layer 120 is located in a first insulating layer 130. The second conductive layer 140 is located in a second insulating layer 150. The bottom surface of the first section 141 contacts the first conductive layer 120 and the first portion 131 of the first insulating layer 130. Next, in step S2, the second current I2 passing through the third section 143 of the second conductive layer 140, the first conductive layer 120 and the fourth section 144 of the second conductive layer 140 is measured. The bottom surface of the fourth section 144 contacts the first conductive layer 120 and the second portion 132 of the first insulating layer 130. The first portion 131 and the second portion 132 of the first insulating layer 130 are respectively located on opposite sides of the first conductive layer 120. Then, in step S3, the first current I1 and the second current I2 are compared to determine whether the center line L1 of the first conductive layer 120 and the symmetric line L2 of the second conductive layer 140 overlap.

Since the operation method of the overlay measurement element 100 includes comparing the first current I1 and the second current I2 to determine whether the center line L1 of the first conductive layer 120 and the symmetry line L2 of the second conductive layer 140 overlap, the overlay measurement using the above operation method is based on the electrical properties of the overlay measurement element 100 instead of using light or electron beam as the measurement signal. Different from the traditional image-based overlay (IBO) measurement, the diffraction-based overlay (DBO) measurement and the in-die overlay measurement that requires the use of a critical dimension scanning electron microscope (CD-SEM), the overlay measurement is not limited by the light or electron beam signal.

In some embodiments, since the center line L1 of the first conductive layer 120 overlaps with the symmetry line L2 of the second conductive layer 140 (as shown in FIG. 2 ), and the first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120 is equal to the second contact area A2 between the fourth section 144 of the second conductive layer 140 and the first conductive layer 120, it can be measured that the first current I1 is equal to the second current I2. That is, when the first current I1 is equal to the second current I2, the center line L1 of the first conductive layer 120 overlaps with the symmetry line L2 of the second conductive layer 140, and the first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120 is equal to the second contact area A2 between the fourth section 144 of the second conductive layer 140 and the first conductive layer 120. In this way, it can be known that there is no overlay shift between the first conductive layer 120 and the second conductive layer 140.

Referring to FIG. 3 and FIG. 4 at the same time, if the first semiconductor exposure machine and the second semiconductor exposure machine used to define the pattern of the first conductive layer 120 and the pattern of the second conductive layer 140 respectively have unexpected deviations/machine differences, the first conductive layer 120 and the second conductive layer 140 will have overlapping displacements. Referring to FIG. 3 , in some embodiments, the symmetry line L2 of the second conductive layer 140 is separated by a distance D on the right side of the center line L1 of the first conductive layer 120, and a first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120 is larger than a second contact area A2 between the fourth section 144 of the second conductive layer 140 and the first conductive layer 120, so that the first current I1 can be measured to be larger than the second current I2. In addition, since the first current I1 and the second current I2 are respectively proportional to the first contact area A1 and the second contact area A2, the distance D between the symmetry line L2 of the second conductive layer 140 and the center line L1 of the first conductive layer 120 can be calculated using the first current I1 and the second current I2. Therefore, when the first current I1 is greater than the second current I2, the symmetry line L2 of the second conductive layer 140 is separated by a distance D on the right side of the center line L1 of the first conductive layer 120, and the distance D can be calculated, and the first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120 is greater than the second contact area A2 between the fourth section 144 of the second conductive layer 140 and the first conductive layer 120.

Referring to FIG. 4 , in some embodiments, the symmetry line L2 of the second conductive layer 140 is separated by a distance D on the left side of the center line L1 of the first conductive layer 120, and a first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120 is smaller than a second contact area A2 between the fourth section 144 of the second conductive layer 140 and the first conductive layer 120, so that the first current I1 can be measured to be greater than the second current I2. Therefore, when the first current I1 is smaller than the second current I2, the symmetry line L2 of the second conductive layer 140 is separated by a distance D on the left side of the center line L1 of the first conductive layer 120, and the distance D can be calculated, and the first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120 is smaller than the second contact area A2 between the fourth section 144 of the second conductive layer 140 and the first conductive layer 120.

Referring to FIG. 1 , the operation method of the stacked measurement element 100 is not limited to the above steps S1 to S3. Steps S1 to S3 may each include a plurality of detailed steps. In some implementations, the operation method of the stacked measurement element 100 may further include other steps in any two of the above steps. In addition, the order of step S1 and step S2 may be reversed.

Referring to FIG. 2 , in some embodiments, when measuring a first current I1 passing through a first segment 141 of the second conductive layer 140, the first conductive layer 120, and the second segment 142 of the second conductive layer 140, a bias voltage V is applied to the first segment 141 and the second segment 142 of the second conductive layer 140; and when measuring a second current I2 passing through a third segment 143 of the second conductive layer 140, the first conductive layer 120, and the fourth segment 144 of the second conductive layer 140, the same bias voltage V is applied to the fourth segment 144 and the third segment 143 of the second conductive layer 140. In this way, since the bias voltages of the first section 141 and the second section 142 of the second conductive layer 140 are the same as the bias voltages of the fourth section 144 and the third section 143 (all bias voltage V), the measurement results of the first current I1 and the second current I2 can be prevented from being affected by the voltage difference, thereby affecting the subsequent calculation of the stack pair displacement. In addition, according to Ohm's law, the operation method of the stack pair measurement element 100 may further include comparing the first resistor and the second resistor corresponding to the first current I1 and the second current I2 respectively to determine whether the center line L1 of the first conductive layer 120 and the symmetric line L2 of the second conductive layer 140 overlap.

It should be understood that the operation methods of the components that have been described will not be repeated, and are described first. In the following description, the structure of the stacked measurement component 100 will be described.

FIG. 5 shows a top view of a stacked measurement device 100 according to an embodiment of the present disclosure. Referring to FIG. 2 and FIG. 5 simultaneously, the stacked measurement device 100 includes a semiconductor substrate 110, a first conductive layer 120, a first insulating layer 130, a second conductive layer 140, and a second insulating layer 150. The semiconductor substrate 110 has a cutting path 112. The first conductive layer 120 is located on the cutting path 112 of the semiconductor substrate 110. The first insulating layer 130 is located on the cutting path 112 of the semiconductor substrate 110 and surrounds the first conductive layer 120. That is, the first conductive layer 120 is in the first insulating layer 130. The first insulating layer 130 has a first portion 131 and a second portion 132 respectively on opposite sides of the first conductive layer 120. The second conductive layer 140 is located on the first conductive layer 120. The second conductive layer 140 has a first section 141, a second section 142, a third section 143 and a fourth section 144 in sequence. The bottom surface of the first section 141 of the second conductive layer 140 contacts the first conductive layer 120 and the first portion 131 of the first insulating layer 130. A first contact area A1 is formed between the first section 141 of the second conductive layer 140 and the first conductive layer 120. The bottom surface of the fourth section 144 of the second conductive layer 140 contacts the first conductive layer 120 and the second portion 132 of the first insulating layer 130. The fourth section 144 of the second conductive layer 140 has a second contact area A2 with the first conductive layer 120. The first section 141, the second section 142, the third section 143, and the fourth section 144 of the second conductive layer 140 have a symmetry line L2. The first section 141 and the second section 142 of the second conductive layer 140 are symmetric with the fourth section 144 and the third section 143 along the symmetry line L2, respectively. Each of the first section 141, the second section 142, the third section 143, and the fourth section 144 of the second conductive layer 140 has the same bottom area. The second insulating layer 150 is located on the first conductive layer 120 and the first insulating layer 130 and surrounds the second conductive layer 140 . In other words, the second conductive layer 140 is in the second insulating layer 150 .

Since there is a first contact area A1 between the first section 141 of the second conductive layer 140 and the first conductive layer 120, and there is a second contact area A2 between the fourth section 144 and the first conductive layer 120, the current passing through the first contact area A1 and the second contact area A2 can be measured and the first contact area A1 and the second contact area A2 can be calculated according to Ohm's law, so that the overlay measurement element 100 can be used to measure the overlay shift between corresponding conductive layers in the chip, so as to correct the error caused by the overlay shift in the subsequent process and improve the yield of the wafer.

In addition, the first section 141, the second section 142, the third section 143 and the fourth section 144 of the second conductive layer 140 of the stacked measuring element 100 have the same first spacing d1 between them. Such a design can fix the path length of the current passing through the first section 141, the second section 142, the third section 143 and the fourth section 144 in the first conductive layer 120.

In some embodiments, the material of the semiconductor substrate 110 of the stacked measurement element 100 may include silicon or silicon carbide, the material of the first conductive layer 120 and the material of the second conductive layer 140 may include metal or polysilicon, and the material of the first insulating layer 130 and the material of the second insulating layer 150 may include nitride or oxide, but is not limited thereto.

It should be understood that the previously described device structures, materials and functions will not be repeated, and are described first. In the following description, other forms of stacked measurement devices will be described.

FIG. 6 shows a top view of a stacked measurement element 100a according to another embodiment of the present disclosure. The stacked measurement element 100a includes a semiconductor substrate 110, a first conductive layer 120, a first insulating layer 130, a second conductive layer 140, and a second insulating layer 150. This embodiment is different from the embodiment of FIG. 5 in that the second conductive layer 140 further has a plurality of fifth segments 145. In this embodiment, the second conductive layer 140 has two fifth segments 145, but this does not limit the present disclosure. The fifth segment 145 is located between the second segment 142 and the third segment 143, and the distance between the two adjacent fifth segments 145 is a first spacing d1. The distance between any one of the second section 142 and the third section 143 and the fifth section 145 is the first spacing d1. Each of the fifth section 145, the first section 141, the second section 142, the third section 143 and the fourth section 144 have the same bottom area. Such a design enables the stacking measurement element 100a to measure a larger stacking displacement. For example, if there is a deviation/machine difference between the first semiconductor exposure machine and the second semiconductor exposure machine used to define the pattern of the first conductive layer 120 and the pattern of the second conductive layer 140 of the stacking measurement element 100a, the symmetry line L2 of the second conductive layer 140 is on the right or left side of the center line L1 of the first conductive layer 120, and the fifth section 145 of the second conductive layer 140 is located on the left side of the center line L1 of the first conductive layer 120. One of them contacts the first conductive layer 120 and the first insulating layer 130. The one of the fifth segment 145 can be found by stacking the electrical properties of the measuring element 100a, and the contact area between the one of the fifth segment 145 and the first conductive layer 120 and the overlap displacement between the second conductive layer 140 and the first conductive layer 120 can be calculated by the current passing through the one of the fifth segment 145.

FIG. 7 shows a top view of a stacked measurement device 100b according to another embodiment of the present disclosure. The stacked measurement device 100b includes a semiconductor substrate 110, a first conductive layer 120, a first insulating layer 130, a second conductive layer 140, and a second insulating layer 150. This embodiment is different from the embodiment of FIG. 6 in that the distance between two adjacent fifth sections 145 of the second conductive layer 140 of the stacked measurement device 100b is a second distance d2, and the second distance d2 is different from the first distance d1.

FIG8 shows a top view of a stacked measurement device 100 c according to another embodiment of the present disclosure. The stacked measurement device 100 c includes a semiconductor substrate 110 , a first conductive layer 120 , a first insulating layer 130 , a second conductive layer 140 , and a second insulating layer 150 . The difference between this embodiment and the embodiment of Figure 5 is that the first segment 141, the second segment 142, the third segment 143 and the fourth segment 144 of the second conductive layer 140 each have a plurality of separate parts, wherein the first segment 141 has a plurality of parts 146, the second segment 142 has a plurality of parts 147, the third segment 143 has a plurality of parts 148, and the fourth segment 144 has a plurality of parts 149, and the top view shape of these parts 146, 147, 148, 149 can be rectangular or square. The distances between adjacent portions 146 of the first section 141 are the same, the distances between adjacent portions 147 of the second section 142 are the same, the distances between adjacent portions 148 of the third section 143 are the same, and the distances between adjacent portions 149 of the fourth section 144 are the same. The top view shapes of the portions 146 of the first section 141, the portions 147 of the second section 142, the portions 148 of the third section 143, and the portions 149 of the fourth section 144 are rectangular. With such a design, since each section has a plurality of portions (e.g., four) along the second direction D2, the stacked pair measuring element 100c for measuring the overlapping displacement along the first direction D1 can perform multiple (e.g., four) measurements along the second direction D2 and have better resolution. In addition, the stacked measuring element 100c can be used to measure the overlapping displacement along the second direction D2.

FIG. 9 shows a top view of a stacked measurement element 100d according to an embodiment of the present disclosure. The stacked measurement element 100d includes a semiconductor substrate 110, a first conductive layer 120, a first insulating layer 130, a second conductive layer 140, and a second insulating layer 150. This embodiment is different from the embodiment of FIG. 8 in that the top view shapes of the first section 141, the second section 142, the third section 143, and the fourth section 144 of the stacked measurement element 100d are circular.

The foregoing summarizes the features of several embodiments so that those skilled in the art can better understand the aspects of the present disclosure. Those skilled in the art should understand that they can easily use the present disclosure as a basis for designing or modifying other processes and structures to achieve the same purpose and/or achieve the same advantages as the embodiments described herein. Those skilled in the art should also recognize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they can make various changes, substitutions and modifications here without departing from the spirit and scope of the present disclosure.

100,100a,100b,100c,100d: stacked measuring element 110: semiconductor substrate 112: cutting path 120: first conductive layer 130: first insulating layer 131: first part 132: second part 140: second conductive layer 141: first section 142: second section 143: third section 144: fourth section 145: fifth section 146,147,148,149: part 150: second insulating layer A1: first contact area A2: second contact area D: distance D1: first direction D2: second direction d1: first spacing d2: second spacing I1: first current I2: second current L1: center line L2: symmetry line V: bias voltage

The disclosure is best understood from the following embodiments when read in conjunction with the accompanying illustrations. Note that various features are not drawn to scale in accordance with standard practice in the industry. In fact, the sizes of various features may be arbitrarily increased or decreased for clarity of discussion. FIG. 1 illustrates a flow chart of a method for operating a stacked measurement element according to an embodiment of the disclosure. FIG. 2 to FIG. 4 illustrate cross-sectional views of stacked measurement elements under different circumstances in accordance with the method for operating a stacked measurement element according to an embodiment of the disclosure. FIG. 5 illustrates a top view of a stacked measurement element according to an embodiment of the disclosure. FIG. 6 illustrates a top view of a stacked measurement element according to another embodiment of the disclosure. FIG. 7 shows a top view of a stacked measurement element according to another embodiment of the present disclosure. FIG. 8 shows a top view of a stacked measurement element according to another embodiment of the present disclosure. FIG. 9 shows a top view of a stacked measurement element according to an embodiment of the present disclosure.

100: Stacked measuring element

110:Semiconductor substrate

112: Cutting Road

120: First conductive layer

130: First insulation layer

131: Part 1

132: Part 2

140: Second conductive layer

141: Section 1

142: Second section

143: The third section

144: Section 4

150: Second insulation layer

A1: First contact area

A2: Second contact area

I1: first current

I2: Second current

L1: Centerline

L2: symmetry line

V: Bias voltage

Claims (11)

An operating method of a stacked measuring element includes: measuring a first current passing through a first section of a second conductive layer on a first conductive layer, and a second section of the first conductive layer and the second conductive layer, wherein the first conductive layer is located in a first insulating layer, the second conductive layer is located in a second insulating layer, and the bottom surface of the first section of the second conductive layer contacts the first conductive layer and a first portion of the first insulating layer; measuring a second current passing through a third section of the second conductive layer, and a fourth section of the first conductive layer and the second conductive layer, The bottom surface of the fourth section of the second conductive layer contacts the first conductive layer and a second part of the first insulating layer, the first part and the second part are respectively located on opposite sides of the first conductive layer, the first section, the second section, the third section and the fourth section of the second conductive layer have a symmetry line, and the first section and the second section are respectively symmetric with the fourth section and the third section along the symmetry line; and the first current and the second current are compared to determine whether a center line of the first conductive layer overlaps with the symmetry line of the second conductive layer. The method for operating the stacked measuring element as described in claim 1 further includes: when the first current is equal to the second current, the center line of the first conductive layer overlaps with the symmetry line of the second conductive layer. The method for operating a stacked measuring element as described in claim 2, wherein when the center line of the first conductive layer overlaps the symmetry line of the second conductive layer, the first contact area between the first section of the second conductive layer and the first conductive layer is equal to the second contact area between the fourth section of the second conductive layer and the first conductive layer. The method for operating the stacked measuring element as described in claim 1 further includes: when the first current is greater than the second current, the symmetry line of the second conductive layer is separated by a distance to the right of the center line of the first conductive layer. The method for operating a stacked measuring element as described in claim 4, wherein when the symmetry line of the second conductive layer is separated by the distance to the right of the center line of the first conductive layer, the first contact area between the first section of the second conductive layer and the first conductive layer is larger than the second contact area between the fourth section of the second conductive layer and the first conductive layer. The method for operating the stacked measuring element as described in claim 1 further includes: when the first current is less than the second current, the symmetry line of the second conductive layer is separated by a distance to the left of the center line of the first conductive layer. The method for operating a stacked measuring element as described in claim 6, wherein when the symmetry line of the second conductive layer is separated by the distance to the left of the center line of the first conductive layer, the first contact area between the first section of the second conductive layer and the first conductive layer is smaller than the second contact area between the fourth section of the second conductive layer and the first conductive layer. The method for operating the stacked measuring element as described in claim 1 further includes: applying a bias voltage to the first segment and the second segment of the second conductive layer when measuring the first current passing through the first segment of the second conductive layer on the first conductive layer, the first conductive layer and the second segment of the second conductive layer; and applying the bias voltage to the fourth segment and the third segment of the second conductive layer when measuring the second current passing through the third segment of the second conductive layer, the first conductive layer and the fourth segment of the second conductive layer. A stacked measurement element includes: a semiconductor substrate having a cutting path; a first conductive layer located on the cutting path of the semiconductor substrate; a first insulating layer located on the cutting path of the semiconductor substrate, surrounding the first conductive layer, and having a first portion and a second portion respectively on two opposite sides of the first conductive layer; a second conductive layer located on the first conductive layer, and having a first section, a second section, a third section, and a fourth section in sequence, wherein the bottom surface of the first section contacts the first conductive layer and the first conductive layer; The first part of the insulating layer, the bottom surface of the fourth section contacts the first conductive layer and the second part of the first insulating layer, the first section, the second section, the third section and the fourth section have a symmetry line, the first section and the second section are symmetrical with the fourth section and the third section respectively along the symmetry line, and each of the first section, the second section, the third section and the fourth section has the same bottom area; and a second insulating layer, located on the first conductive layer and the first insulating layer, and surrounding the second conductive layer. The stacked measuring element as described in claim 9, wherein the first segment and the second segment and the third segment and the fourth segment of the second conductive layer have the same first spacing, and the second conductive layer further has a plurality of fifth segments, the fifth segments are located between the second segment and the third segment, and the distance between two adjacent fifth segments is the first spacing or a second spacing different from the first spacing. The stacked measuring element as described in claim 9, wherein the first section, the second section, the third section and the fourth section of the second conductive layer each have a plurality of separated parts, the distance between two adjacent parts is the same, and the top view shape of the parts is rectangular or circular.

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