De-embedding method for transmission lines

Abstract

A de-embedding method of a transmission line, comprising: a first transmission line test structure and a second transmission line test structure, a difference between a first transmission line length size in the first transmission line test structure and a second transmission line length size in the second transmission line test structure being a length size of a difference transmission line; obtaining a first transmission parameter matrix A' of the first transmission line test structure L1 , and a second transmission parameter matrix A' of the second transmission line test structure L2 ; obtaining a virtual transmission parameter matrix A' L ; obtaining an intrinsic admittance parameter matrix Y'' of the difference transmission line L . The transmission parameter matrix of a set of transmission line test structures is used for targeted calculation, the measurement parasitic corresponding to the measurement part in the virtual transmission parameter matrix is eliminated, the accurate intrinsic transmission parameter matrix of the difference transmission line is extracted from the virtual transmission parameter matrix to achieve the de-embedding effect, and finally the accurate intrinsic admittance parameter matrix of the difference transmission line is obtained to improve the measurement accuracy of the transmission line in the actual device structure.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and in particular to a method for de-embedding transmission lines. Background Technology

[0002] Integrated circuits formed on a semiconductor substrate include multiple active and passive components, such as resistors, inductors, capacitors, transistors, and amplifiers. These components are manufactured according to design specifications, which define the ideal electrical characteristics of these components. Generally, it is desirable to verify that each component conforms to its specific design specifications; however, after components are integrated into an integrated circuit, individual components are often not easily tested. Therefore, standalone copies of individual components in the integrated circuit are fabricated on a wafer, and the electrical characteristics of these standalone copies are then measured. The standalone copies are manufactured using the same processes as the components in the integrated circuit and have the same electrical characteristics. Therefore, the electrical characteristics obtained by measuring the standalone copies are the electrical characteristics of the components in the integrated circuit.

[0003] Independently replicated components are generally referred to as Device Under Test (DUT). During testing, the DUT is electrically connected to leads and test pads, which are further electrically connected to a Vector Network Analyzer (VNA). From the VNA, various parameters of the DUT can be obtained, including S-parameters (scattering parameters), Y-parameters (admittance parameters), Z-parameters (impedance parameters), and H-parameters. These parameters can be used to characterize the electrical characteristics of the DUT. When the DUT is used in high-frequency microwave circuits, scattering parameters (S-parameters) are typically used to characterize its electrical properties. However, parasitic effects generated by the leads and test pads are also included in the various parameters of the DUT during measurement. Therefore, de-embedding is usually used to subtract these parasitic effects to obtain the actual electrical characteristics of the DUT.

[0004] However, existing de-embedding methods still have many problems. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a method for de-embedding transmission lines, which removes the influence of parasitic effects caused by wire connections and test pads in the test structure, thereby improving the accuracy of intrinsic transmission line characteristic measurements.

[0006] To solve the above-mentioned technical problems, the present invention provides a method for de-embedding transmission lines, comprising: providing a set of test structures for de-embedding transmission lines, including: a first transmission line test structure and a second transmission line test structure, wherein the first transmission line test structure includes a first transmission line and a first measuring part electrically connected to both sides of the first transmission line, the first transmission line having a first length dimension; the second transmission line test structure includes a second transmission line and a second measuring part electrically connected to both sides of the second transmission line, the second transmission line having a second length dimension; the first length dimension being greater than the second length dimension, and the difference between the first length dimension and the second length dimension being the length dimension of the difference transmission line; and obtaining a first transmission parameter matrix A′ of the first transmission line test structure. L1 and the second transmission parameter matrix A′ of the second transmission line test structure. L2 According to the first transmission parameter matrix A′ L1 and the second transmission parameter matrix A′ L2 Obtain the virtual transmission parameter matrix A′ L The virtual transmission parameter matrix A′ L It includes the intrinsic transmission parameter matrix A characterizing the differential transmission line. L1-L2 And the parasitic transport parameter matrix A characterizing the measurement of parasitic effects. PL and According to the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L .

[0007] Optionally, obtain the first transmission parameter matrix A′ of the first transmission line test structure. L1 The method includes: measuring the first transmission line test structure using a vector network analyzer to obtain the first scattering parameter matrix S of the first transmission line test structure. L1 Based on the transformation between the parameters of the two-port network, the first scattering parameter matrix S is... L1 Converted into the first transmission parameter matrix A′ L1 ; Obtain the second transmission parameter matrix A′ of the second transmission line test structure. L2 The method includes: measuring the second transmission line test structure using a vector network analyzer to obtain the second scattering parameter matrix S of the second transmission line test structure. L2 Based on the transformation between the parameters of the two-port network, the second scattering parameter matrix S is... L2 Converted to the second transmission parameter matrix A′ L2 .

[0008] Optionally, in obtaining the first scattering parameter matrix SL1 Following this, it also includes: verifying the first scattering parameter matrix S L1 S in 11 With S 22 Are they equal, and S 12 With S 21 Are they equal? ​​This is done when obtaining the second scattering parameter matrix S. L2 Following this, it also includes: verifying the second scattering parameter matrix S L2 S in 11 With S 22 Are they equal, and S 12 With S 21 Are they equal?

[0009] Optionally, the first transmission parameter matrix A′ L1 Includes: the transmission parameter matrix A of the first transmission line L1 The transmission parameter matrix A of the first measuring section on both sides of the first transmission line PL and A PR ,Right now:

[0010] A′ L1 =A PL A L1 A PR .

[0011] Optionally, the second transmission parameter matrix A′ L2 Includes: the transmission parameter matrix A of the second transmission line L2 The transmission parameter matrix A of the second measuring units on both sides of the second transmission line PL and A PR ,Right now:

[0012] A′ L2 =A PL A L2 A PR .

[0013] Optionally, according to the first transmission parameter matrix A L1 and the second transmission parameter matrix A L2 Obtain the virtual transmission parameter matrix A′ L The method includes: multiplying the first transmission parameter matrix by the inverse of the second transmission parameter matrix to obtain the virtual transmission parameter matrix A′. L ,Right now:

[0014]

[0015] Optionally, based on the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. LThe method includes: based on the virtual transmission parameter matrix A′ L A virtual transmission line test structure is established, comprising the differential transmission line and virtual measurement units electrically connected to both sides of the differential transmission line, wherein the intrinsic transmission parameter matrix of the differential transmission line is A. L1-L2 The transmission parameter matrices of the virtual measurement units on both sides are A PL and The virtual transmission parameter matrix A′ L Convert to admittance parameter matrix Y′ L Wherein, the admittance parameter matrix Y′ L Including the intrinsic admittance parameter matrix Y″ of the differential transmission line L And the lumped parasitic admittance parameter matrix Y of the virtual measurement unit PP That is: Y′ L =Y″ L +Y PP Remove the admittance parameter matrix Y′ L The lumped parasitic admittance parameter matrix Y in PP Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L .

[0016] Optionally, the virtual transmission parameter matrix A′ L Convert to admittance parameter matrix Y′ L The method includes: transforming the virtual transmission parameter matrix A′ according to the conversion between various parameters of the two-port network. L Converted to the admittance parameter matrix Y′ L .

[0017] Optionally, the admittance parameter matrix Y′ is removed. L The lumped parasitic admittance parameter matrix Y in PP Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L The methods include: defining a 2×2 matrix commutation formula, Swap, that is:

[0018]

[0019] For the admittance parameter matrix Y′ L Perform matrix swapping to obtain the swap admittance parameter matrix Swap(Y′). L The intrinsic admittance parameter matrix Y″ L Let Y′ be the admittance parameter matrix. L With the exchange admittance parameter matrix Swap(Y′) L The sum of ) divided by 2, that is:

[0020]

[0021] Optionally, the length of the differential transmission line is equal to the second length.

[0022] Compared with the prior art, the technical solution of the embodiments of the present invention has the following beneficial effects:

[0023] The transmission line de-embedding method provided by this invention involves providing a set of transmission line test structures with different lengths, where the difference in transmission line lengths within the set of test structures is exactly equal to the length of the differential transmission line. A virtual transmission parameter matrix is ​​then calculated based on the transmission parameter matrix of the set of test structures. This virtual transmission parameter matrix includes the intrinsic transmission parameter matrix of the differential transmission line. Finally, the intrinsic admittance parameter matrix of the differential transmission line is obtained based on the virtual transmission parameter matrix. By using the transmission parameter matrix of the set of test structures for targeted calculations, measurement parasites corresponding to the measurement section in the virtual transmission parameter matrix are eliminated. The accurate intrinsic transmission parameter matrix of the differential transmission line is extracted from the virtual transmission parameter matrix, achieving a de-embedding effect. Ultimately, the accurate intrinsic admittance parameter matrix of the differential transmission line is obtained, thereby improving the measurement accuracy of transmission lines in actual device structures.

[0024] Furthermore, the length of the differential transmission line is equal to the second length. During measurement, to reduce interference from external test structures, it is recommended that both transmission lines be at least 100µm in length, and that the size of the differential transmission line be chosen such that it is an integer, to facilitate unit adjustment during subsequent parameter extraction. In actual layout design, considering layout size limitations, the transmission line size is generally below 1000µm. Simultaneously, to minimize the impact of parasitic interactions on intrinsic transmission lines, the length of the differential transmission line is generally equal to or greater than the length of the second transmission line. By selecting the first length as twice the second length, making the length of the differential transmission line equal to the second length, the parameters of the de-embedding differential transmission line and the parameters of the un-embedding second transmission line can be obtained simultaneously, facilitating comparison of the de-embedding effect of the differential transmission line. Attached Figure Description

[0025] Figure 1 This is a flowchart of the transmission line de-embedding method according to an embodiment of the present invention;

[0026] Figures 2 to 6 This is a schematic diagram of the steps in the transmission line de-embedding method of this invention. Detailed Implementation

[0027] As described in the background section, existing de-embedding methods still have many problems. These will be explained in detail below.

[0028] In the high-frequency domain, especially in the millimeter-wave (wavelength less than 10mm) band, where the wavelength is comparable to the component size on the chip, various high-frequency effects of transmission lines and substrate losses become increasingly significant. Traditional open-short de-embedding methods not only require additional test structures but also struggle to clearly distinguish the de-embedding structure from the intrinsic transmission line test structure. Furthermore, the transmission line itself has relatively small parameters, and the parasitic parameters introduced by the test pads are almost equivalent to the intrinsic parameters, making de-embedding extremely difficult.

[0029] To address the aforementioned problems, this invention provides a method for de-embedding transmission lines. This method involves providing a set of transmission line test structures with varying lengths, where the difference in length among the transmission lines in the set is exactly equal to the length of the differential transmission line. A virtual transmission parameter matrix is ​​then calculated based on the transmission parameter matrix of the set of test structures. This virtual transmission parameter matrix includes the intrinsic transmission parameter matrix of the differential transmission line. Finally, the intrinsic admittance parameter matrix of the differential transmission line is obtained based on the virtual transmission parameter matrix. By using the transmission parameter matrix of the set of test structures for calculation, an accurate intrinsic transmission parameter matrix of the differential transmission line can be obtained from the virtual transmission parameter matrix. Furthermore, by performing targeted calculations, the transmission parameter matrix corresponding to the measurement section in the virtual transmission parameter matrix is ​​eliminated, ultimately resulting in an accurate acquisition of the intrinsic admittance parameter matrix of the differential transmission line, thereby improving the measurement accuracy of transmission lines in actual device structures.

[0030] To make the above-mentioned objectives, features and beneficial effects of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0031] Figure 1 This is a flowchart of a transmission line de-embedding method according to an embodiment of the present invention, including:

[0032] Step S101: Provide a set of test structures for transmission line de-embedding, including: a first transmission line test structure and a second transmission line test structure. The first transmission line test structure includes a first transmission line and a first measuring part electrically connected to both sides of the first transmission line. The first transmission line has a first length dimension. The second transmission line test structure includes a second transmission line and a second measuring part electrically connected to both sides of the second transmission line. The second transmission line has a second length dimension. The first length dimension is greater than the second length dimension, and the difference between the first length dimension and the second length dimension is the length dimension of the difference transmission line.

[0033] Step S102: Obtain the first transmission parameter matrix A′ of the first transmission line test structure. L1 and the second transmission parameter matrix A′ of the second transmission line test structure. L2 ;

[0034] Step S103, according to the first transmission parameter matrix A′ L1 and the second transmission parameter matrix A′ L2 Obtain the virtual transmission parameter matrix A′ L The virtual transmission parameter matrix A′ L It includes the intrinsic transmission parameter matrix A characterizing the differential transmission line. L1-L2 And the parasitic transport parameter matrix A characterizing the measurement of parasitic effects. PL and

[0035] Step S104, according to the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L .

[0036] The following describes in detail each step of the de-embedding method for the transmission line with reference to the accompanying drawings.

[0037] Figures 2 to 6 This is a schematic diagram of the structure of each step of the transmission line de-embedding method according to an embodiment of the present invention.

[0038] Please refer to Figure 2 A set of test structures for transmission line de-embedding is provided, including: a first transmission line test structure 100 and a second transmission line test structure 200. The first transmission line test structure 100 includes a first transmission line 101 and a first measuring part 102 electrically connected to both sides of the first transmission line 101. The first transmission line 101 has a first length dimension L1. The second transmission line test structure 200 includes a second transmission line 201 and a second measuring part 202 electrically connected to both sides of the second transmission line 201. The second transmission line 201 has a second length dimension L2. The first length dimension L1 is greater than the second length dimension L2, and the difference between the first length dimension L1 and the second length dimension L2 is the length dimension of the difference transmission line.

[0039] It should be noted that, in this embodiment, the length of the differential transmission line is the same as the length of the transmission line in the actual device structure. Therefore, the subsequent calculation results of the differential transmission line are equivalent to the test results of the transmission line in the actual device structure.

[0040] In this embodiment, the transmission line in the actual device structure is a micro-strip line. This method can also be applied to improved transmission lines such as coplanar waveguides (CPW) and slow-wave coplanar waveguides.

[0041] In this embodiment, the first measurement unit 102 is used to subsequently measure and obtain the first transmission parameter matrix A′ of the first transmission line test structure 100. L1 At that time, the first measuring unit 102 performs a needle puncture measurement; the second measuring unit 202 is used for subsequent measurements to obtain the second transmission parameter matrix A′ of the second transmission line test structure 200. L2 At that time, needle puncture measurement is performed through the second measuring unit 200.

[0042] In this embodiment, the length of the differential transmission line is equal to the second length L2. During measurement, to reduce interference from external test structures, it is recommended that both transmission lines be at least 100µm in length, and that the differential transmission line be selected as an integer to facilitate unit adjustment during subsequent parameter extraction. In actual layout design, considering layout size limitations, the transmission line size is generally below 1000µm. Simultaneously, to minimize the impact of parasitic interactions on intrinsic transmission lines, the length of the differential transmission line is generally equal to or greater than the length of the second transmission line 201. Selecting the first length as twice the second length, making the length of the differential transmission line equal to the second length, allows for simultaneous acquisition of the parameters of the de-embedding differential transmission line and the parameters of the un-embedding second transmission line 201, facilitating comparison of the de-embedding effect.

[0043] Please refer to Figure 3 Obtain the first transmission parameter matrix A′ of the first transmission line test structure 100. L1 And obtain the second transmission parameter matrix A′ of the second transmission line test structure 200. L2 .

[0044] In this embodiment, the first transmission parameter matrix A′ of the first transmission line test structure 100 is obtained. L1 The method includes: measuring the first transmission line test structure 100 using a vector network analyzer (VNA) to obtain the first scattering parameter matrix S of the first transmission line test structure 100. L1 Based on the transformation between the parameters of the two-port network, the first scattering parameter matrix S is... L1 Converted into the first transmission parameter matrix A′ L1 .

[0045] In this embodiment, after obtaining the first scattering parameter matrix S L1 Following this, it also includes: verifying the first scattering parameter matrix S L1 S in 11 With S 22 Are they equal, and S 12 With S 21 Are they equal? ​​Because the scattering parameter matrix of the transmission line contains S... 11 equals S 22 and S 12 equals S 21 Therefore, given the characteristics of the first scattering parameter matrix, it is necessary to verify the first scattering parameter matrix S after obtaining it. L1 S in 11 With S 22 Are they equal, and S 12 With S 21 Whether they are equal is to ensure the design accuracy of the first transmission line test structure.

[0046] In this embodiment, the second transmission parameter matrix A′ of the second transmission line test structure 200 is obtained. L2 The method includes: measuring the second transmission line test structure 200 using a vector network analyzer (VNA) to obtain the second scattering parameter matrix S of the second transmission line test structure 200. L2 Based on the transformation between the parameters of the two-port network, the second scattering parameter matrix S is... L2 Converted to the second transmission parameter matrix A′ L2 .

[0047] In this embodiment, when obtaining the second scattering parameter matrix S L2 Following this, it also includes: verifying the second scattering parameter matrix S L2 S in 11 With S 22 Are they equal, and S 12 With S 21 Are they equal? ​​Because the scattering parameter matrix of the transmission line contains S... 11 equals S 22 and S 12 equals S 21 Therefore, given the characteristics of the second scattering parameter matrix, it is necessary to verify the second scattering parameter matrix S after obtaining it. L2 S in 11 With S 22 Are they equal, and S 12 With S 21Whether they are equal is to ensure the design accuracy of the second transmission line test structure.

[0048] It should be noted that the scattering parameter matrix (i.e., the S-parameter matrix) is an important parameter in microwave transmission, where S... 12 S is the reverse transmission coefficient, which represents isolation; 21 S is the forward transmission coefficient, which is also the gain; 11 S is the input reflection coefficient, which is also the input return loss; 22 The output reflection coefficient is the output return loss.

[0049] Please continue to refer to this. Figure 3 According to the first transmission parameter matrix A′ L1 and the second transmission parameter matrix A′ L2 Obtain the virtual transmission parameter matrix A′ L The virtual transmission parameter matrix A′ L It includes the intrinsic transmission parameter matrix A characterizing the differential transmission line. L1-L2 And the parasitic transport parameter matrix A characterizing the measurement of parasitic effects. PL and

[0050] In this embodiment, the first transmission parameter matrix A′ L1 Includes: the transmission parameter matrix A of the first transmission line 101 L1 The transmission parameter matrix A of the first measuring units 102 on both sides of the first transmission line 101 PL and A PR ,Right now:

[0051] A′ L1 =A PL A L1 A PR .

[0052] In this embodiment, the second transmission parameter matrix A′ L2 Includes: the transmission parameter matrix A of the second transmission line 201 L2 The transmission parameter matrix A of the second measuring units 202 on both sides of the second transmission line 201 PL and A PR ,Right now:

[0053] A′ L2 =A PL A L2 A PR .

[0054] It should be noted that, in this embodiment, the first test section 102 and the second test section 202 located on the same side of the first transmission line test structure 100 and the second transmission line test structure 200 have the same structure. Therefore, in the first transmission parameter matrix A′ L1 and the second transmission parameter matrix A′ L2 All use A PL and A PR Characterization.

[0055] In this embodiment, according to the first transmission parameter matrix A L1 and the second transmission parameter matrix A L2 Obtain the virtual transmission parameter matrix A′ L The method includes: multiplying the first transmission parameter matrix by the inverse of the second transmission parameter matrix to obtain the virtual transmission parameter matrix A′. L ,Right now:

[0056]

[0057] It should be noted that, in this embodiment, since the test section structures located on both sides of the transmission line are symmetrical, A PR and The product of these is an identity matrix, and the intrinsic transmission parameter matrix of the difference transmission line 301 is A. L1-L2 That is, A L1 and The product of.

[0058] In this embodiment, when obtaining the virtual transmission parameter matrix A′ L Following this, it also includes: according to the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L Please refer to the detailed process. Figures 4 to 6 .

[0059] Please refer to Figure 4 According to the virtual transmission parameter matrix A′ L A virtual transmission line test structure 300 is established, which includes a differential transmission line 301 and a virtual measurement unit 302 electrically connected to both sides of the differential transmission line 301.

[0060] In this embodiment, the intrinsic transmission parameter matrix of the differential transmission line 301 is A. L1-L2 The transmission parameter matrices of the virtual measurement units on both sides are A PL and

[0061] Please refer to Figure 5The virtual transmission parameter matrix A′ L Convert to admittance parameter matrix Y′ L .

[0062] In this embodiment, the virtual measurement unit 302 and the difference transmission line 301 located on the left can be modeled using lumped admittance Y. L The virtual measurement unit 302 and the differential transmission line 301 located on the right can be modeled using lumped admittance -Y. L Considering both virtual measurement units 302 together, the two virtual measurement units 302 can be converted into a Y-axis connected in parallel with the difference transmission line 301. PP The transfer matrix, i.e., the admittance parameter matrix Y′ L Including the intrinsic admittance parameter matrix Y″ of the differential transmission line L And the lumped parasitic admittance parameter matrix Y of the virtual measurement unit PP That is: Y′ L =Y″ L +Y PP .

[0063] in,

[0064] In this embodiment, the virtual transmission parameter matrix A′ is... L Convert to admittance parameter matrix Y′ L The method includes: transforming the virtual transmission parameter matrix A′ according to the conversion between various parameters of the two-port network. L Converted to the admittance parameter matrix Y′ L .

[0065] It should be noted that Y in the admittance parameter matrix (i.e., the Y parameter matrix) 11 This indicates the control effect of the input voltage on the input current; Y 12 This indicates the control effect of the output voltage on the input current; Y 21 This indicates the control effect of the input voltage on the output current; Y 22 This indicates the control effect of the output voltage on the output current. 11 Y 12 Y 21 and Y 22 The units are all in the admittance unit "Siemens", hence it is called "admittance parameter matrix" or "Y parameter matrix".

[0066] Please refer to Figure 6 Remove the admittance parameter matrix Y′ L The lumped parasitic admittance parameter matrix Y in PP Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L.

[0067] Remove the admittance parameter matrix Y′ L The lumped parasitic admittance parameter matrix Y in PP Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L The methods include: defining a 2×2 matrix commutation formula, Swap, that is:

[0068]

[0069] For the admittance parameter matrix Y′ L Perform matrix swapping to obtain the swap admittance parameter matrix Swap(Y′). L The intrinsic admittance parameter matrix Y″ L Let Y′ be the admittance parameter matrix. L With the exchange admittance parameter matrix Swap(Y′) L The sum of ) divided by 2, that is:

[0070]

[0071] Please continue to refer to this. Figure 6 In this embodiment, Y′ L +Swap(Y′ L It can be equivalent to in Figure 5 Based on this, a virtual transmission line test structure Swap(Y′) is connected in parallel. L ).

[0072] In the above formula, Swap(Y′) L =Swap(Y″) L +Y PP =Swap(Y″) L )+Swap(Y PP );

[0073] Because the inherent differential transmission line 301 has symmetric properties, Swap(Y″) L )=Y″ L However, the virtual measurement unit 302 does not have symmetry, therefore

[0074]

[0075] therefore:

[0076]

[0077] In this embodiment, a set of transmission line test structures with different lengths is provided, and the difference in the lengths of the transmission lines in the set of test structures is exactly equal to the length of the differential transmission line. Then, a virtual transmission parameter matrix A′ is obtained by calculating based on the transmission parameter matrix of the set of test structures. L The virtual transmission parameter matrix A′ L The intrinsic transmission parameter matrix A of the differential transmission line is included. L1-L2 Finally, based on the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix of the differential transmission line. Perform targeted calculations using the transmission parameter matrices of a set of transmission line test structures to obtain the virtual transmission parameter matrix A′. L The measurement parasitics corresponding to the measurement section are eliminated from the virtual transmission parameter matrix A′. L Extract the accurate intrinsic transmission parameter matrix A of the differential transmission line 301. L1-L2 To achieve the de-embedding effect, the accurate intrinsic admittance parameter matrix Y″ of the differential transmission line 301 is finally obtained. L This is to improve the accuracy of measurements of transmission lines in actual device structures.

[0078] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A method for de-embedding transmission lines, characterized in that, include: A set of test structures for transmission line de-embedding is provided, including: a first transmission line test structure and a second transmission line test structure. The first transmission line test structure includes a first transmission line and a first measuring part electrically connected to both sides of the first transmission line. The first transmission line has a first length dimension. The second transmission line test structure includes a second transmission line and a second measuring part electrically connected to both sides of the second transmission line. The second transmission line has a second length dimension. The first length dimension is greater than the second length dimension, and the difference between the first length dimension and the second length dimension is the length dimension of the difference transmission line. Obtain the first transmission parameter matrix A′ of the first transmission line test structure. L1 and the second transmission parameter matrix A′ of the second transmission line test structure. L2 ; According to the first transmission parameter matrix A′ L1 and the second transmission parameter matrix A′ L2 Obtain the virtual transmission parameter matrix A′ L The virtual transmission parameter matrix A′ L It includes the intrinsic transmission parameter matrix A, which characterizes the differential transmission line. L1-L2 And the parasitic transport parameter matrix A characterizing the measurement of parasitic effects. PL and According to the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L .

2. The de-embedding method for transmission lines as described in claim 1, characterized in that, Obtain the first transmission parameter matrix A′ of the first transmission line test structure. L1 The method includes: measuring the first transmission line test structure using a vector network analyzer to obtain the first scattering parameter matrix S of the first transmission line test structure. L1 Based on the transformation between the parameters of the two-port network, the first scattering parameter matrix S is... L1 Converted into the first transmission parameter matrix A′ L1 ; Obtain the second transmission parameter matrix A′ of the second transmission line test structure. L2 The method includes: measuring the second transmission line test structure using a vector network analyzer to obtain the second scattering parameter matrix S of the second transmission line test structure. L2 Based on the transformation between the parameters of the two-port network, the second scattering parameter matrix S is... L2 Converted to the second transmission parameter matrix A′ L2 .

3. The de-embedding method for transmission lines as described in claim 2, characterized in that, In obtaining the first scattering parameter matrix S L1 Following this, it also includes: verifying the first scattering parameter matrix S L1 S in 11 With S 22 Are they equal, and S 12 With S 21 Are they equal? ​​This is done when obtaining the second scattering parameter matrix S. L2 Following this, it also includes: verifying the second scattering parameter matrix S L2 S in 11 With S 22 Are they equal, and S 12 With S 21 Are they equal? 4. The de-embedding method for transmission lines as described in claim 1, characterized in that, The first transmission parameter matrix A′ L1 Includes: the transmission parameter matrix A of the first transmission line L1 The transmission parameter matrix A of the first measuring units on both sides of the first transmission line PL and A PR ,Right now: A′ L1 =A PL A L1 A PR 。 5. The de-embedding method for transmission lines as described in claim 4, characterized in that, The second transmission parameter matrix A′ L2 Includes: the transmission parameter matrix A of the second transmission line L2 The transmission parameter matrix A of the second measuring units on both sides of the second transmission line PL and A PR ,Right now: A′ L2 =A PL A L2 A PR 。 6. The de-embedding method for transmission lines as described in claim 5, characterized in that, According to the first transmission parameter matrix A L1 and the second transmission parameter matrix A L2 Obtain the virtual transmission parameter matrix A′ L The method includes: multiplying the first transmission parameter matrix by the inverse of the second transmission parameter matrix to obtain the virtual transmission parameter matrix A′. L ,Right now:

7. The de-embedding method for transmission lines as described in claim 6, characterized in that, According to the virtual transmission parameter matrix A′ L Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L The method includes: based on the virtual transmission parameter matrix A′ L A virtual transmission line test structure is established, comprising the differential transmission line and virtual measurement units electrically connected to both sides of the differential transmission line, wherein the intrinsic transmission parameter matrix of the differential transmission line is A. L1-L2 The transmission parameter matrices of the virtual measurement units on both sides are A PL and The virtual transmission parameter matrix A′ L Convert to admittance parameter matrix Y′ L Wherein, the admittance parameter matrix Y′ L Including the intrinsic admittance parameter matrix Y″ of the differential transmission line L And the lumped parasitic admittance parameter matrix Y of the virtual measurement unit PP That is: Y′ L =Y″ L +Y PP Remove the admittance parameter matrix Y′ L The lumped parasitic admittance parameter matrix Y in PP Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L .

8. The de-embedding method for transmission lines as described in claim 7, characterized in that, The virtual transmission parameter matrix A′ L Convert to admittance parameter matrix Y′ L The method includes: transforming the virtual transmission parameter matrix A′ according to the conversion between various parameters of the two-port network. L Converted to the admittance parameter matrix Y′ L .

9. The de-embedding method for transmission lines as described in claim 7, characterized in that, Remove the admittance parameter matrix Y′ L The lumped parasitic admittance parameter matrix Y in PP Obtain the intrinsic admittance parameter matrix Y″ of the differential transmission line. L The methods include: defining a 2×2 matrix commutation formula, Swap, that is: For the admittance parameter matrix Y′ L Perform matrix swapping to obtain the swap admittance parameter matrix Swap(Y′). L The intrinsic admittance parameter matrix Y″ L Let Y′ be the admittance parameter matrix. L With the exchange admittance parameter matrix Swap(Y′) L The sum of ) divided by 2, that is:

10. The de-embedding method for a transmission line as described in claim 1, characterized in that, The length of the differential transmission line is equal to the second length dimension.

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