Method for preparing calibration piece and calibration piece

Abstract

The present invention provides a method for preparing a calibration part and a calibration part. The method comprises: determining the cross-sectional dimensions of a transmission line; when the cross-sectional dimensions meet the preset frequency requirements of the calibration part, optimizing the cross-sectional dimensions to obtain the optimal cross-sectional dimensions; setting multiple groups of transmission lines based on the optimal cross-sectional dimensions, determining the target transmission line whose characteristic impedance is closest to the preset impedance value among the multiple groups of transmission lines, and determining the corresponding calibration part dimensions based on the target transmission line; performing semiconductor process processing according to the calibration part dimensions, and laser trimming the resistance of the load calibration part in the processed calibration part, and setting the values ​​of all calibration parts after the trimming. The present invention can improve the design success rate and efficiency, and effectively overcome the deviation caused by process errors.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave characteristic measurement of wafer-level semiconductor devices, and in particular to a method for preparing a calibration piece and the calibration piece. Background Art

[0002] A large number of "on-wafer S-parameter test systems" in the microelectronics industry need to use on-wafer calibration parts combined with corresponding calibration methods to perform vector error correction before use. The calibration of vector network analyzers used to characterize transistor performance generally uses commercial impedance standards (ISS), including open-short-load-through (SOLT) calibration parts made on ceramic substrates, transmission line-reflection-matching (LRM) calibration parts, and transmission line-reflection-reflection-matching (LRRM) calibration parts. ISS is characterized by low cost, ease of use and durability.

[0003] The transmission line structure is a coplanar waveguide CPW. In China, electromagnetic simulation methods are generally used in the design of calibration parts. However, the limited accuracy of electromagnetic simulation models, the single structure of calibration parts, and poor process have led to problems such as the impedance of the designed straight-through calibration parts deviating from 50Ω and the inconsistent resistance of the load calibration parts. Summary of the invention

[0004] The embodiment of the present invention provides a method for preparing a calibration piece and a calibration piece, so as to solve the problem of deviation of the calibration piece which occurs when the calibration piece is prepared by using an electromagnetic simulation model in the prior art.

[0005] In a first aspect, an embodiment of the present invention provides a method for preparing a calibration piece, comprising:

[0006] Determine the cross-sectional dimensions of the transmission line;

[0007] When the cross-sectional dimensions meet the preset calibration component frequency requirements, the cross-sectional dimensions are optimized to obtain the optimal cross-sectional dimensions;

[0008] Setting a plurality of groups of transmission lines based on the optimal cross-sectional dimensions, determining a target transmission line whose characteristic impedance is closest to a preset impedance value among the plurality of groups of transmission lines, and determining a corresponding calibration piece size based on the target transmission line;

[0009] Semiconductor processing is performed according to the size of the calibration piece, and the resistance of the load calibration piece in the processed calibration piece is laser trimmed, and all the calibration pieces after the resistance trimming are fixed.

[0010] In a possible implementation, determining the cross-sectional size of the transmission line includes:

[0011] Obtaining substrate thickness, substrate dielectric constant, conductivity and metal thickness of a metal disposed on the substrate;

[0012] The cross-sectional size of the transmission line is obtained according to the substrate thickness, the substrate dielectric constant, the conductivity and the metal thickness.

[0013] In a possible implementation, the optimizing the cross-sectional dimensions to obtain the optimal cross-sectional dimensions includes:

[0014] Changing the cross-sectional dimensions within a first preset step range to obtain multiple sets of cross-sectional dimensions;

[0015] The transmission lines of the plurality of sets of cross-sectional dimensions and preset lengths are simulated, and the S 11 The cross-sectional dimension corresponding to the minimum value is determined as the optimal cross-sectional dimension.

[0016] In a possible implementation, a method for determining whether the cross-sectional dimension meets the preset calibration component frequency requirement includes:

[0017] calculating the calibration piece frequency based on the cross-sectional dimensions;

[0018] When the calibration part frequency is greater than or equal to the preset calibration part frequency, it is determined that the cross-sectional size meets the preset calibration part frequency requirement.

[0019] In a possible implementation, calculating the frequency of the calibration piece according to the cross-sectional size includes:

[0020] according to Calculate the calibration frequency;

[0021] Where, f is the calibration frequency, g is the distance between the center conductor and the corresponding floor, w is the width of the center conductor, μ0 is the air permeability, ε0 ​​is the air dielectric constant, and ε r represents the substrate dielectric constant, and h represents the substrate thickness.

[0022] In a possible implementation, the setting of multiple groups of transmission lines based on the optimal cross-sectional dimensions and determining a target transmission line whose characteristic impedance is closest to a preset impedance value among the multiple groups of transmission lines includes:

[0023] The optimal cross-sectional dimensions are varied within a second preset step range to obtain a plurality of sets of optimal cross-sectional dimensions, and different transmission line layout processes are performed based on the plurality of sets of optimal cross-sectional dimensions and at least three lengths corresponding to each set of optimal cross-sectional dimensions;

[0024] The characteristic impedance of the transmission line is calibrated using a preset resistor;

[0025] Based on the transmission line layout and the preset resistance, the characteristic impedance of each transmission line is measured, and the transmission line corresponding to the characteristic impedance closest to the impedance value of the preset resistance is determined as the target transmission line.

[0026] In a possible implementation, performing semiconductor process according to the size of the calibration piece includes:

[0027] Prepare a mask corresponding to the strip line and the resistor according to the determined calibration piece size;

[0028] Cleaning and drying the ceramic substrate, and polishing any one side of the ceramic substrate;

[0029] sputtering a resistance layer on the polished surface of the ceramic substrate;

[0030] sputtering an alloy layer on the resistance layer;

[0031] Electroplating metal on the strip lines in the mask pattern on the surface of the alloy layer;

[0032] The surface of the calibration piece with the metal strip line is coated with photoresist, and the alloy and the resistor outside the mask pattern are corroded away in sequence to obtain the calibration piece.

[0033] In a possible implementation, the cleaning and drying of the ceramic substrate includes:

[0034] In a first cleaning solution, the ceramic substrate is boiled within a preset temperature range for a first preset time, then taken out and rinsed with water until the pH of the ceramic substrate is neutral;

[0035] Soaking the ceramic substrate processed in the first step in hydrofluoric acid for a second preset time, and rinsing with water until the pH of the ceramic substrate is neutral;

[0036] In the second cleaning solution, the ceramic substrate processed in the second step is boiled at the preset temperature for the first preset time, then taken out and rinsed with water until the pH of the ceramic substrate is neutral;

[0037] The ceramic substrate was blown dry using dry filtered nitrogen;

[0038] The first cleaning solution is a mixture of water, ammonia and hydrogen peroxide, and the volume ratios thereof are 4:1:1 respectively;

[0039] The second cleaning solution is a mixture of water, hydrochloric acid and hydrogen peroxide, and the volume ratios thereof are 4:1:1 respectively;

[0040] The preset temperature range is a range consisting of 80°C to 90°C;

[0041] The first preset time is any time between 10 minutes and 15 minutes;

[0042] The second preset time is 2 minutes.

[0043] In a possible implementation, the resistance layer is made of NiC or TaN; the thickness of the resistance layer is any value between 40nm and 100nm;

[0044] The alloy layer is made of Ti / W; the thickness of the alloy layer is any value between 50nm and 1μm;

[0045] The strip line is made of gold with a purity greater than 90%, and the strip line is electroplated with a thickness ranging from 1 μm to 10 μm.

[0046] In a second aspect, an embodiment of the present invention provides a calibration piece, including: prepared by the method for preparing a calibration piece described in any of the above embodiments.

[0047] The embodiment of the present invention provides a method for preparing a calibration part and a calibration part, by first designing the size of the calibration part, and then preparing the calibration part according to the size of the calibration part, thereby obtaining the calibration part. When designing the size of the calibration part, in the present application, after calculating the cross-sectional size of the transmission line, a plurality of sets of step sizes are used for two verifications according to the cross-sectional size of the transmission line, thereby improving the design success rate and efficiency and effectively overcoming the deviation caused by the process error. When preparing the calibration part, a low-resistivity resistor is designed under the transmission line to increase the attenuation and make the frequency response of the transmission line smoother. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0049] Figure 1 is a flow chart of a method for preparing a calibration piece provided by an embodiment of the present invention;

[0050] Figure 2 is a side view of a straight-through calibration component provided by an embodiment of the present invention;

[0051] Figure 3 is a top view of a straight-through calibration component provided by an embodiment of the present invention;

[0052] Figure 4 is a schematic diagram of a short-circuit calibration component provided by an embodiment of the present invention;

[0053] Figure 5 is a side view of a load calibration component provided by an embodiment of the present invention;

[0054] Figure 6 is a flow chart of semiconductor processing of a calibration piece provided by an embodiment of the present invention;

[0055] Figure 7 It is a schematic diagram of a through calibration component provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0056] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0057] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0058] Figure 1 The present invention provides a flow chart for implementing a method for preparing a calibration part according to an embodiment of the present invention. The calibration parts generally include five types of calibration parts: SOLT, LRRM, LRM, TRL, and Multiline TRL. Common implementation forms include straight-through transmission lines, open-circuit calibration parts, short-circuit calibration parts, and load calibration parts. The straight-through transmission line is a two-port calibration part, and the open-circuit calibration part, short-circuit calibration part, and load calibration part are two single-port calibration parts. The load calibration part is generally a 50Ω or 100Ω resistor. The design process of the calibration part is described in detail as follows:

[0059] Step 101, determining the cross-sectional dimensions of the transmission line.

[0060] The cross-sectional dimensions of the transmission line include the width w of the center conductor and the distance g between the center conductor and the corresponding ground plane, such as Figure 2 Side view of the Thru Calibration Kit shown, Figure 3 Shown is a top view of the thru calibration. Figure 2 and Figure 3 The floor width g1 is also included, g1=k1(2g+w), and the value of k1 is any value from 0.3 to 3. In this way, when the width w of the center conductor and the distance g between the center conductor and the corresponding floor are determined, the floor width can be determined.

[0061] Optionally, this step of determining the cross-sectional dimensions of the transmission line may include:

[0062] The substrate thickness, substrate dielectric constant, conductivity of the metal disposed on the substrate and the metal thickness are obtained; and the cross-sectional dimensions of the transmission line are obtained according to the substrate thickness, substrate dielectric constant, conductivity and metal thickness.

[0063] Here, simulation software is used to input substrate thickness, substrate dielectric constant, conductivity and metal thickness to obtain the corresponding transmission line cross-sectional dimensions, that is, the width w of the center conductor and the spacing g between the center conductor and the corresponding floor. The simulation software may be EMPRO.

[0064] Step 102: When the cross-sectional dimensions meet the preset calibration component frequency requirements, the cross-sectional dimensions are optimized to obtain the optimal cross-sectional dimensions.

[0065] Before this step, it may also include: detecting whether the cross-sectional dimensions meet the preset calibration part frequency requirements, and executing step 102 when the cross-sectional dimensions meet the preset calibration part frequency requirements, and returning to step 101 to execute when the cross-sectional dimensions do not meet the preset calibration part frequency requirements.

[0066] Optionally, when detecting whether the cross-sectional dimensions meet the preset calibration part frequency requirements, the calibration part frequency can be calculated based on the cross-sectional dimensions; and then detecting whether the calibration part frequency is greater than or equal to the preset calibration part frequency. It should be noted that the preset calibration part frequency is the required calibration part frequency, such as the customer's requirements. The calibration part frequency calculated based on the cross-sectional dimensions is the theoretical maximum frequency of the transmission line, that is, the calibration part frequency corresponding to the cross-sectional dimensions is greater than or equal to the calibration part frequency required by the customer.

[0067] Optionally, when the calibration part frequency is greater than or equal to a preset calibration part frequency, it is determined that the cross-sectional size meets the preset calibration part frequency requirement.

[0068] Optionally, calculate the calibration piece frequency based on the cross-sectional dimensions, including:

[0069] according to Calculate the calibration frequency;

[0070] Where, f is the calibration frequency, g is the distance between the center conductor and the corresponding floor, w is the width of the center conductor, μ0 is the air permeability, ε0 ​​is the air dielectric constant, and ε r represents the substrate dielectric constant, and h represents the substrate thickness.

[0071] In this step, the cross-sectional dimensions are optimized to obtain the optimal cross-sectional dimensions, which is based on the S parameter. 11 For the purpose of simulation, the cross-sectional dimensions are optionally optimized to obtain the optimal cross-sectional dimensions, including:

[0072] Changing the cross-sectional dimensions within a first preset step range to obtain multiple sets of cross-sectional dimensions;

[0073] Simulate multiple sets of transmission lines with preset cross-sectional dimensions and lengths, and 11 The cross-sectional dimension corresponding to the minimum value is determined as the optimal cross-sectional dimension.

[0074] Optionally, the first preset step range is 1 μm to 5 μm. That is, w and g are both stepped by 1 μm to 5 μm, and the value ranges are (w-5 to w+5) μm and (g-5 to g+5) μm, respectively. For example, multiple groups of cross-sectional dimensions can be (w-1) μm and (g-1) μm, (w-2) μm and (g-2) μm, (w+3) μm and (g+3) μm, etc.

[0075] The preset length may be any value between 100 μm and 500 μm, for example, the transmission line may be a 100 μm transmission line, a 200 μm transmission line, etc.

[0076] We input the multiple sets of cross-sectional dimensions and preset lengths of the transmission lines determined above into the simulation software, and we can obtain the S corresponding to each transmission line. 11 , select S 11 The cross-sectional dimension corresponding to the minimum value is determined as the optimal cross-sectional dimension.

[0077] When optimizing the cross-sectional dimensions in this step, multiple sets of stepping dimensions are used for simulation verification according to the cross-sectional dimensions of the transmission line, so as to obtain the optimal cross-sectional dimensions, improve the design success rate and efficiency, and effectively overcome the deviation caused by process errors.

[0078] Step 103, setting multiple groups of transmission lines based on the optimal cross-sectional dimensions, determining a target transmission line whose characteristic impedance is closest to a preset impedance value among the multiple groups of transmission lines, and determining a corresponding calibration piece size based on the target transmission line.

[0079] After determining the optimal cross-sectional dimensions, the layout is processed to determine the dimensions of the transmission line with the characteristic impedance closest to 50Ω. Therefore, the preset impedance value here is 50Ω.

[0080] Optionally, this step may include:

[0081] The optimal cross-sectional dimensions are varied within a second preset step range to obtain a plurality of sets of optimal cross-sectional dimensions, and different transmission line layout processes are performed based on the plurality of sets of optimal cross-sectional dimensions and at least three lengths corresponding to each set of optimal cross-sectional dimensions;

[0082] The characteristic impedance of the transmission line is calibrated using a preset resistor;

[0083] Based on the transmission line layout and the preset resistance, the characteristic impedance of each transmission line is measured, and the transmission line corresponding to the characteristic impedance closest to the impedance value of the preset resistance is determined as the target transmission line.

[0084] Here, the second preset step range is different from the first preset step range. The second preset step range can be 0.5 μm to 1 μm. Therefore, the multiple sets of optimal cross-sectional dimensions obtained can be (w-0.5) μm and (g-0.5) μm, (w-1) μm and (g-1) μm, (w+1) μm and (g+1) μm, and so on.

[0085] The preset resistor may be a 50Ω resistor.

[0086] In this step, when designing the target transmission line, multiple sets of step sizes are used according to the cross-sectional size of the transmission line, and different transmission line lengths are used for simulation verification, so that the target transmission line closest to the preset impedance value can be obtained, thereby improving the design success rate and efficiency and effectively overcoming the deviation caused by process errors.

[0087] The calibration parts include open-circuit calibration parts, short-circuit calibration parts and load calibration parts. The sizes of the corresponding open-circuit calibration parts, short-circuit calibration parts and load calibration parts are determined based on the target transmission line. Generally, the short-circuit calibration parts, open-circuit calibration parts and load calibration parts are two identical calibration parts that exist at the same time. In this way, the left and right metal pieces of the two short-circuit calibration parts are exactly the same in size, the left and right metal pieces of the two open-circuit calibration parts are exactly the same in size, and the left and right metal pieces of the two load calibration parts are exactly the same in size, and the sizes of the four resistors are also consistent, such as Figure 4 The short-circuit calibration kit shown and Figure 5 Load calibration kit shown. See Figure 4 and Figure 5 The distance between the leftmost figure and the rightmost figure of the two short-circuit calibration pieces, two open-circuit calibration pieces and two load calibration pieces is the same as the distance of the straight-through transmission line. The width of the strip line of the short-circuit calibration pieces, open-circuit calibration pieces and load calibration pieces is generally 35μm to 60μm. There are two forms of open circuit. One is that the probe in the S-parameter test system does not touch anything to achieve an open circuit, and the other is that the load calibration piece is removed after the resistor is removed to achieve an open circuit.

[0088] See also Figure 4 and Figure 5 , ws1=ws2 in the short circuit calibration piece, the values ​​of ws1 and ws2 are greater than 30μm, and the values ​​of ws1 and ws2 are generally in the range of 40μm to 100μm. The through length is (ws1+ws2+D)μm. For example Figure 4 D=100μm, ws1=ws2=50μm, L=650μm. Figure 5In the figure, wL1=wL2=50μm, g2=260.5μm and the width of the center conductor is w2 of the load calibration piece. Figure 5 The R in the figure represents resistance, and the resistance value can be 50Ω or 100Ω.

[0089] Step 104, perform semiconductor process processing according to the size of the calibration piece, perform laser resistance trimming on the resistance of the load calibration piece in the processed calibration piece, and set the value of all the calibration pieces after the resistance trimming.

[0090] Optionally, after the size of the calibration piece is determined, semiconductor processing of the calibration piece can be performed. Figure 6 As shown, the details are as follows:

[0091] Step 601, preparing a mask corresponding to the strip lines and resistors according to the determined calibration piece size.

[0092] The calibration piece adopts two processes, strip line and resistor, so the corresponding mask is prepared according to the determined calibration piece size. Here, there are strip line and resistor patterns on the mask, and other patterns need to be cleaned.

[0093] Step 602, cleaning and drying the ceramic substrate, and polishing any one side of the ceramic substrate.

[0094] The ceramic substrate may be a single-side polished 996 ceramic substrate. Before preparing the calibration piece, the substrate needs to be cleaned and dried.

[0095] In this step, cleaning and drying the ceramic substrate may include:

[0096] In the first cleaning solution, the ceramic substrate is boiled within a preset temperature range for a first preset time, then taken out and rinsed with water until the pH of the ceramic substrate is neutral; the ceramic substrate processed in the first step is immersed in hydrofluoric acid for a second preset time, and rinsed with water until the pH of the ceramic substrate is neutral; in the second cleaning solution, the ceramic substrate processed in the second step is boiled at a preset temperature for a first preset time, then taken out and rinsed with water until the pH of the ceramic substrate is neutral; the ceramic substrate is blown dry using dried and filtered nitrogen.

[0097] The first cleaning solution is a mixture of water, ammonia and hydrogen peroxide, and the volume ratios thereof are 4:1:1 respectively;

[0098] The second cleaning solution is a mixture of water, hydrochloric acid and hydrogen peroxide, and the volume ratio thereof is 4:1:1 respectively;

[0099] The preset temperature range is 80° C. to 90° C. It should be noted that when cooking in the first cleaning liquid or the second cleaning liquid, it is sufficient to keep the temperature between 80° C. and 90° C., and it is not necessary to keep the temperature constant during the cooking process.

[0100] The first preset time is any time between 10 minutes and 15 minutes;

[0101] The second preset time is 2 minutes.

[0102] Step 603: sputtering a resistor layer on the polished surface of the ceramic substrate.

[0103] After the ceramic substrate is cleaned and dried, a resistance layer is sputtered on the polished surface of the ceramic substrate using a magnetron sputtering device.

[0104] Optionally, the material of the resistance layer is NiC or TaN; the thickness of the resistance layer is any value between 40nm and 100nm.

[0105] When preparing calibration parts, designing low-resistivity resistors under the transmission line can increase attenuation and make the frequency response of the transmission line smoother.

[0106] Step 604: sputtering an alloy layer on the resistor layer.

[0107] The alloy layer is sputtered on the resistor layer using a magnetron sputtering device.

[0108] Optionally, the alloy layer is made of Ti / W, wherein the ratio of Ti to W may be 3:1; and the thickness of the alloy layer is any value between 50 nm and 1 μm. The thickness of the alloy layer may be 50 nm, 100 nm, or 1 μm.

[0109] Step 605, electroplating metal on the strip lines in the mask pattern on the surface of the alloy layer.

[0110] Using electroplating equipment, the strip lines in the mask pattern are electroplated with gold with a purity greater than 90% on the surface of the Ti / W alloy. For example, the purity of the gold is 90%, 95%, 99%, etc. Preferably, 99% gold is used.

[0111] Optionally, the strip line is made of gold with a purity of 99%, and the strip line electroplating thickness is any value from 1 μm to 10 μm, for example, the strip line electroplating thickness can be 1 μm, 4.7 μm, 6 μm, 10 μm, etc.

[0112] After electroplating, cleaning and drying are required.

[0113] Step 606, coating photoresist on the surface of the calibration piece with the metal strip line, and etching away the alloy and resistor outside the mask pattern in sequence to obtain the calibration piece.

[0114] After the electroplating is completed, the alloy layer and resistor layer outside the mask pattern need to be etched away, leaving only the alloy layer and resistor layer corresponding to the pattern area. Figure 7The prepared through calibration piece is shown, wherein 701 is a ceramic substrate, 702 is a NiCr resistor, 703 is a Ti / W alloy, and 704 is gold.

[0115] It should be noted that when preparing different calibration parts, only different mask plates need to be processed, and the subsequent processes of step 601 to step 606 remain unchanged.

[0116] After executing step 606, the prepared calibration piece needs to be cleaned and dried, and then the calibration piece is tested under a microscope to see if it is qualified. Here, the microscopic inspection refers to checking whether the calibration piece meets the conditions under a microscope. If it meets the conditions, it is a qualified product, and if it does not meet the conditions, it is a waste product. The objects of the microscopic inspection can be whether the gold on the calibration piece is obviously too coarse or too fine, whether there is excess photoresist, etc.

[0117] After the calibration piece is processed, the resistors in the load calibration piece are laser trimmed, which can be performed using a resistor trimming system in the prior art and will not be described in detail here.

[0118] After the resistance is repaired, the calibration piece is calibrated. At this time, the multi-line TRL calibration method can be used to calibrate the open circuit calibration piece, the short circuit calibration piece, and the load calibration piece. It should be noted that during the calibration piece calibration process, the needle tip distance used for calibration piece calibration is ensured to be consistent with the needle tip distance when the multi-line TRL calibration method is used for self-calibration, so as to reduce the influence of parasitic parameters on the calibration accuracy.

[0119] The method for preparing the calibration part is to first design the size of the calibration part, and then prepare the calibration part according to the size of the calibration part, so as to obtain the calibration part. When designing the size of the calibration part, the present application calculates the cross-sectional size of the transmission line and then uses multiple sets of step sizes to perform two verifications according to the cross-sectional size of the transmission line, thereby improving the design success rate and efficiency and effectively overcoming the deviation caused by the process error. When preparing the calibration part, designing a low-resistivity resistor under the transmission line can increase the attenuation and make the frequency response of the transmission line smoother.

[0120] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0121] An embodiment of the present invention further provides a calibration piece, which is prepared by the method for preparing the calibration piece described in any of the above embodiments, and has the beneficial effects produced in the process of preparing the calibration piece in any of the above embodiments.

[0122] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for preparing a calibration piece, characterized in that: include: Determine the cross-sectional dimensions of the transmission line; When the cross-sectional dimensions meet the preset calibration component frequency requirements, the cross-sectional dimensions are optimized to obtain the optimal cross-sectional dimensions; The step of optimizing the cross-sectional dimensions to obtain an optimal cross-sectional dimension includes: Changing the cross-sectional dimensions within a first preset step range to obtain multiple sets of cross-sectional dimensions; The transmission lines of the plurality of sets of cross-sectional dimensions and preset lengths are simulated, and the The cross-sectional dimension corresponding to the minimum value is determined as the optimal cross-sectional dimension; Setting a plurality of groups of transmission lines based on the optimal cross-sectional dimensions, determining a target transmission line whose characteristic impedance is closest to a preset impedance value among the plurality of groups of transmission lines, and determining a corresponding calibration piece size based on the target transmission line; The step of setting a plurality of groups of transmission lines based on the optimal cross-sectional dimensions and determining a target transmission line in the plurality of groups of transmission lines whose characteristic impedance is closest to a preset impedance value comprises: The optimal cross-sectional dimensions are varied within a second preset step range to obtain a plurality of sets of optimal cross-sectional dimensions, and different transmission line layout processes are performed based on the plurality of sets of optimal cross-sectional dimensions and at least three lengths corresponding to each set of optimal cross-sectional dimensions; The characteristic impedance of the transmission line is calibrated using a preset resistor; Based on the transmission line layout and the preset resistance, the characteristic impedance of each transmission line is measured, and the transmission line corresponding to the characteristic impedance closest to the impedance value of the preset resistance is determined as the target transmission line; Performing semiconductor process processing according to the size of the calibration piece, and performing laser resistance trimming on the resistance of the load calibration piece in the processed calibration piece, and setting the value of all the calibration pieces after the resistance trimming; Determining the cross-sectional size of the transmission line includes: Obtaining substrate thickness, substrate dielectric constant, conductivity and metal thickness of a metal disposed on the substrate; Obtaining a cross-sectional dimension of a transmission line according to the substrate thickness, the substrate dielectric constant, the conductivity and the metal thickness; The method for determining whether the cross-sectional dimensions meet the preset calibration component frequency requirements includes: calculating the calibration piece frequency based on the cross-sectional dimensions; When the calibration part frequency is greater than or equal to the preset calibration part frequency, determining that the cross-sectional size meets the preset calibration part frequency requirement; The step of calculating the frequency of the calibration piece according to the cross-sectional dimensions comprises: according to Calculate the calibration frequency; in, Indicates the calibration frequency, Indicates the distance between the center conductor and the corresponding ground plane. Indicates the width of the center conductor, represents the magnetic permeability of air, represents the dielectric constant of air, represents the substrate dielectric constant, Indicates the substrate thickness.

2. The method for preparing a calibration piece according to claim 1, characterized in that: The semiconductor process is performed according to the size of the calibration piece, including: Prepare a mask corresponding to the strip line and the resistor according to the determined calibration piece size; Cleaning and drying the ceramic substrate, and polishing any one side of the ceramic substrate; sputtering a resistance layer on the polished surface of the ceramic substrate; sputtering an alloy layer on the resistance layer; Electroplating metal on the strip lines in the mask pattern on the surface of the alloy layer; The surface of the calibration piece with the metal strip line is coated with photoresist, and the alloy and the resistor outside the mask pattern are corroded away in sequence to obtain the calibration piece.

3. The method for preparing a calibration piece according to claim 2, characterized in that: The cleaning and drying of the ceramic substrate comprises: In a first cleaning solution, the ceramic substrate is boiled within a preset temperature range for a first preset time, then taken out and rinsed with water until the pH of the ceramic substrate is neutral; Soaking the ceramic substrate processed in the first step in hydrofluoric acid for a second preset time, and rinsing with water until the pH of the ceramic substrate is neutral; In the second cleaning solution, the ceramic substrate processed in the second step is boiled at the preset temperature for the first preset time, then taken out and rinsed with water until the pH of the ceramic substrate is neutral; The ceramic substrate was blown dry using dry filtered nitrogen; The first cleaning solution is a mixture of water, ammonia and hydrogen peroxide, and the volume ratios thereof are 4:1:1 respectively; The second cleaning solution is a mixture of water, hydrochloric acid and hydrogen peroxide, and the volume ratios thereof are 4:1:1 respectively; The preset temperature range is a range consisting of 80°C to 90°C; The first preset time is any time between 10 minutes and 15 minutes; The second preset time is 2 minutes.

4. The method for preparing a calibration piece according to claim 2, characterized in that: The material of the resistance layer is NiC or TaN; the thickness of the resistance layer is any value between 40 nm and 100 nm; The alloy layer is made of Ti / W; the thickness of the alloy layer is 50nm to 1 Any value in ; The strip line is made of gold with a purity greater than 90%, and the thickness of the strip line electroplating is 1 Up to 10 Any value in .

5. A calibration piece, characterized in that: include: The calibration piece is prepared by the method for preparing the calibration piece according to any one of claims 1 to 4.

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