A size correction method for a resonant structure for detecting the dielectric constant of LTCC materials

Abstract

The present invention relates to a method for correcting the size of a resonant structure for detecting the dielectric constant of an LTCC material, comprising the following steps: designing a planar resonator structure and setting an initial resonant frequency; performing simulation using HFSS to obtain an actual resonant frequency through simulation; obtaining, through simulation, the actual resonant frequencies corresponding to each dimension within a parameterized scanned dimension range, and finding an actual resonant frequency consistent with the initial resonant frequency; calculating a correction coefficient; and using the correction coefficient to correct the size of the planar resonator structure. The present invention has the following beneficial effects: the resonant structure size correction method of the present invention, through multiple simulation optimizations and verification using resonant ring patterns with different resonant frequencies, obtains correction coefficients for different resonant structure dimensions, thereby significantly shortening the resonant structure size optimization process, making the actual resonant frequency of the designed resonant structure closer to the resonant frequency, and improving design efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of dielectric constant measurement in high-frequency environment measurement, and in particular relates to a size correction method of a resonant structure for detecting the dielectric constant of LTCC materials. Background Art

[0002] In microelectronics technology, the most important microelectronic device is the radio frequency module, which is mostly composed of passive components. The requirements for passive components in the military and aerospace industries are becoming increasingly stringent. The accuracy of the dielectric constant of the substrate materials used in passive components in the high-frequency range limits the precision of microelectronic devices.

[0003] In the frequency range of 1GHz to 15GHz, the dielectric constant of the passive component substrate material can be calculated using equipment such as a vector network analyzer or SPDR in combination with relevant programs; however, there are fewer methods for measuring the dielectric constant in the frequency range of 15GHz to 50GHz, and the cost is relatively high.

[0004] The development of microelectronics has led to the emergence of low-temperature co-fired ceramic (LTCC) technology, which is now used in many passive component substrates. The coupled resonant ring method is well-suited for measuring the dielectric constant of passive component substrates at high frequencies. Because the resonant structure used to measure the dielectric constant of LTCC passive component substrates is also manufactured using LTCC technology, the coupled resonant ring method provides a more accurate and cost-effective way to measure the dielectric constant of LTCC passive component substrates.

[0005] The resonant structure is a circular or polygonal resonant ring, mostly quadrilateral, hexagonal, octagonal, and decagonal resonant rings. However, in the process of measuring the dielectric constant of the LTCC passive component substrate, the size requirements for the resonant ring structure are very high. The actual designed resonant structure size is quite different from the size corresponding to the simulation result, resulting in a large gap between the dielectric constant measured by the coupled resonant ring method and the simulation result, requiring multiple size optimizations. The actual resonant frequency of the resonant structure used can gradually approach the target resonant frequency, and then the dielectric constant of the LTCC passive component substrate can be accurately measured. With the help of this dielectric constant test method, the precision of microelectronic devices can be improved.

[0006] However, there is almost no method for correcting the size of the resonant ring structure in the prior art. Summary of the Invention

[0007] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for correcting the size of a resonant structure for detecting the dielectric constant of LTCC materials.

[0008] The method for correcting the size of a resonant structure for detecting the dielectric constant of an LTCC material comprises the following steps:

[0009] Step 1: According to the material of the low-temperature co-fired ceramic (LTCC) passive component substrate, the empirical value of the initial dielectric constant ε of the low-temperature co-fired ceramic passive component substrate of this material is given. e (f); and design e (f) corresponding planar resonator structures having circular resonant rings or polygonal resonant rings of different sizes; and setting resonant frequencies for the planar resonator structures having circular resonant rings or polygonal resonant rings of different sizes;

[0010] Step 2: Use HFSS to simulate the planar resonator structure of circular resonant rings or polygonal resonant rings of different sizes designed in Step 1, and obtain the actual resonant frequency through simulation; compare the actual resonant frequency with the initial resonant frequency, and find that the actual resonant frequency is inconsistent with the initial resonant frequency, and there is a certain difference;

[0011] Step 3: Based on the set resonant frequency value, a size range of the planar resonator structure is given; in HFSS, a parametric sweep is performed on each dimension within the size range, and the actual resonant frequency corresponding to each dimension in the parametric sweep size range is obtained through simulation. The actual resonant frequency that is consistent with the initial resonant frequency is found, and the planar resonator structure size used in the parametric sweep corresponding to the actual resonant frequency is used as the optimal size;

[0012] Step 4: Use the parametric sweep to obtain the optimal size of the planar resonator structure, and divide it by the empirical value of the initial dielectric constant ε of the low-temperature co-fired ceramic passive component substrate. e (f) The corresponding circumference of the resonator structure is used to obtain the correction factor K;

[0013] Step 5: Use the correction coefficient K obtained in step 4 to correct the perimeter of the polygonal resonant ring or the circular resonant ring, and then correct the size of the planar resonator structure.

[0014] Preferably, step 4 is specifically as follows:

[0015] The selected dimension of the planar resonator structure obtained by parametric sweep is the perimeter of the polygonal resonant ring. The perimeter formula of the polygonal resonant ring is:

[0016] L1=Na

[0017] In the above formula, L1 is the perimeter of the polygonal resonant ring, N is the number of sides of the polygonal resonant ring, N is a positive integer; a is the side length of the polygon;

[0018] When a planar resonator structure resonates, the circumference of the electron orbit is an integer multiple of the wavelength of the phase wave after the electromagnetic wave passes through the material. The circumference of the electron orbit is:

[0019] L2=nλ

[0020] In the above formula, n is the resonance order, λ is the wavelength of the phase wave after the electromagnetic wave passes through the material, c is the speed of light in vacuum, and the value of c is 3×10 8 m / s, ε e (f) is the empirical value of the initial dielectric constant of the low-temperature co-fired ceramic passive component substrate; f is the resonant frequency of the planar resonator structure set by circular resonant rings or polygonal resonant rings of different sizes;

[0021] but:

[0022]

[0023] Then the correction coefficient K is:

[0024]

[0025] When the number of sides N of the polygonal resonant ring approaches infinity, the polygonal resonant ring is equivalent to the circular resonant ring, then:

[0026]

[0027] Preferably, step 5 is specifically as follows:

[0028] When the planar resonator structure is a polygonal resonant ring, the perimeter of the modified polygonal resonant ring is L1′:

[0029] L1′=Na=Knλ

[0030]

[0031] In the above formula, L1′ is the circumference of the corrected polygonal resonant ring, K is the correction coefficient, n is the resonance order, and c is the speed of light in vacuum, which is 3×10 8 m / s; ε e (f) is the empirical value of the initial dielectric constant of the low-temperature co-fired ceramic passive component substrate.

[0032] Preferably, step 5 is specifically as follows:

[0033] When the planar resonator structure is a circular resonant ring, the circumference of the modified circular resonant ring is L1″:

[0034]

[0035] In the above formula, R is the radius of the circular resonant ring.

[0036] Preferably, the resonance order n=1.

[0037] The beneficial effects of the present invention are as follows: the resonant structure size correction method of the present invention is verified by multiple simulation optimizations using resonant ring graphics with different resonant frequencies, and correction coefficients for different resonant structure sizes are obtained, which can greatly shorten the size optimization process of the resonant structure, make the actual resonant frequency of the designed resonant structure closer to the resonant frequency, and improve design efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the quadrilateral resonant ring structure;

[0039] Figure 2 This is a diagram showing the effect of the present invention on the size correction of the quadrilateral resonant structure;

[0040] Figure 3 Schematic diagram of the hexagonal resonant ring structure;

[0041] Figure 4 This is a diagram showing the effect of the present invention on the size correction of the hexagonal resonant structure;

[0042] Figure 5 Schematic diagram of the octagonal resonant ring structure;

[0043] Figure 6 This is a diagram showing the effect of the present invention on the size correction of the octagonal resonant structure;

[0044] Figure 7 Schematic diagram of the decagonal resonant ring structure;

[0045] Figure 8 This is a diagram showing the effect of the present invention on the size correction of the decagonal resonant structure;

[0046] Figure 9 Schematic diagram of the circular resonant ring structure;

[0047] Figure 10 This is a diagram showing the effect of the present invention on the size correction of a circular resonant structure;

[0048] Figure 11 This is a diagram showing the comprehensive effect of the present invention on the size correction of circular and polygonal resonant structures.

[0049] Description of the accompanying drawings: substrate 1, ground terminal 2, quadrilateral resonant ring 3, hexagonal resonant ring 4, octagonal resonant ring 5, decagonal resonant ring 6, circular resonant ring 7. DETAILED DESCRIPTION

[0050] The present invention will be further described below with reference to the following examples. The following examples are provided only to facilitate understanding of the present invention. It should be noted that, without departing from the principles of the present invention, it is possible for a person skilled in the art to make various modifications to the present invention, and such improvements and modifications fall within the scope of the claims of the present invention.

[0051] Example 1

[0052] A method for correcting the size of a resonant structure for detecting the dielectric constant of an LTCC material comprises the following steps:

[0053] Step 1: According to the material of the low-temperature co-fired ceramic (LTCC) passive component substrate, set the resonant frequency of the dielectric constant to be measured, and give the initial dielectric constant empirical value ε of the low-temperature co-fired ceramic passive component substrate of this material. e (f); Designed with ε e (f) The corresponding planar resonator structures of circular resonant rings or polygonal resonant rings of different sizes.

[0054] Step 2: Use HFSS to simulate the circular resonant ring or polygonal resonant ring planar resonator structures of different sizes designed in Step 1. After simulation, switch to Eigenmode and view the actual resonant frequency in Solution Data. Comparing the actual resonant frequency with the set resonant frequency, it is found that the actual resonant frequency is inconsistent with the set resonant frequency, indicating that there is a certain error.

[0055] Step 3: Based on the set resonant frequency, a size range of the planar resonator structure is given; in HFSS, a parametric sweep is performed on each dimension within the size range, and the actual resonant frequency corresponding to each dimension in the parametric sweep size range is obtained through simulation. The actual resonant frequency that is consistent with the set resonant frequency is found, and the planar resonator structure size used in the parametric sweep corresponding to the actual resonant frequency is used as the optimal size;

[0056] Step 4: Use the parametric sweep to obtain the optimal size of the planar resonator structure, and divide it by the empirical value of the initial dielectric constant ε of the low-temperature co-fired ceramic passive component substrate. e (f) The circumference of the corresponding electron orbital is used to obtain the correction factor K;

[0057] The optimal size of the planar resonator structure obtained by parametric sweep is the perimeter of the polygonal resonant ring. The formula for the perimeter of the polygonal resonant ring is:

[0058] L1=Na

[0059] In the above formula, L1 is the perimeter of the polygonal resonant ring, N is the number of sides of the polygonal resonant ring, N is a positive integer; a is the side length of the polygon;

[0060] When a planar resonator structure resonates, the circumference of the electron orbit is an integer multiple of the wavelength of the phase wave after the electromagnetic wave passes through the material. The circumference of the electron orbit is:

[0061] L2=nλ

[0062] In the above formula, n is the resonance order, λ is the wavelength of the phase wave after the electromagnetic wave passes through the material, c is the speed of light in vacuum, and the value of c is 3×10 8 m / s, ε e (f) is the empirical value of the initial dielectric constant of the low-temperature co-fired ceramic passive component substrate; f is the initial resonant frequency of the planar resonator structure set by circular resonant rings or polygonal resonant rings of different sizes;

[0063] but:

[0064]

[0065] Then the correction coefficient K is:

[0066]

[0067] The optimal dimensions of the planar resonator structure obtained by multiple sets of parametric sweeps are divided by the circumference of the electron orbit, and then the average value is calculated to obtain the correction coefficient K;

[0068] When the number of sides N of the polygonal resonant ring approaches infinity, the polygonal resonant ring is equivalent to the circular resonant ring, then:

[0069]

[0070] Step 5: Use the correction coefficient K obtained in step 4 to correct the circumference of the polygonal resonant ring or the circular resonant ring, and then correct the size of the planar resonator structure;

[0071] When the planar resonator structure is a polygonal resonant ring, the perimeter of the modified polygonal resonant ring is L1′:

[0072] L1′=Na=Knλ

[0073]

[0074] In the above formula, L1′ is the circumference of the corrected polygonal resonant ring, K is the correction coefficient, n is the resonance order, and c is the speed of light in vacuum, which is 3×10 8 m / s; ε e (f) is the empirical value of the initial dielectric constant of the low-temperature co-fired ceramic passive component substrate;

[0075] When the planar resonator structure is a circular resonant ring, the circumference of the modified circular resonant ring is L1″:

[0076]

[0077] In the above formula, R is the radius of the circular resonant ring;

[0078]

[0079] When the circumference of the planar resonator structure is an integer multiple of the wavelength of the medium (LTCC passive component substrate), the resonant structure is in a resonant state; the resonant structure in a resonant state couples the strongest signal to the output end, facilitating the measurement of the dielectric constant of the LTCC passive component substrate.

[0080] Based on the revised formula, by performing HFSS simulation on planar resonator structures with different resonant frequencies and comparing the actual resonant frequency with the initial resonant frequency, the error is significantly reduced, which can greatly improve simulation efficiency and save simulation time.

[0081] Example 2

[0082] According to the method of Example 1, the set resonant frequency f = 5 GHz, the number of side lengths N = 4 and the corresponding correction coefficient K = 1.1063 of the planar resonator structure set by the quadrilateral resonant structure are input to obtain the side length a of the polygonal resonant ring; in this embodiment, a = 6.9000 mm is obtained; the designed planar resonator structure is as follows Figure 1 As shown, the effect of this embodiment on the size correction of the quadrilateral resonant structure is as follows Figure 2 shown.

[0083] Example 3

[0084] According to the method of Example 1, the initial resonant frequency f = 5 GHz, the number of side lengths N = 6 and the corresponding correction coefficient K = 1.0938 of the planar resonator structure set by the hexagonal resonant ring are input to obtain the side length a of the hexagonal resonant ring; in this embodiment, a = 4.5400 mm is obtained; the designed planar resonator structure is as follows Figure 3 As shown, the effect of this embodiment on the size correction of the hexagonal resonant structure is as follows Figure 4 shown.

[0085] Example 4

[0086] According to the method of Example 1, the initial resonant frequency f = 5 GHz, the side length N = 8 and the corresponding correction coefficient K = 1.4140 of the planar resonator structure set by the octagonal resonant ring are input to obtain the side length a of the polygonal resonant ring; in this embodiment, a = 4.4100 mm is obtained; the designed planar resonator structure is as follows Figure 5 As shown, the effect of this embodiment on the size correction of the octagonal resonant structure is as follows Figure 6 shown.

[0087] Example 5

[0088] According to the method of Example 1, the initial resonant frequency f = 5 GHz, the number of side lengths N = 10 and the corresponding correction coefficient K = 1.8004 of the planar resonator structure set by the decagonal resonant ring are input to obtain the side length a of the polygonal resonant ring; in this embodiment, a = 4.4900 mm is obtained; the designed planar resonator structure is as follows Figure 7 As shown, the size correction effect of this embodiment on the decagonal resonant structure is as follows Figure 8 shown.

[0089] Example 6

[0090] According to the method of Example 1, the initial resonant frequency f = 5 GHz, the period Na = 2πR and the corresponding correction coefficient K = 1.0930 of the planar resonator structure set by the circular resonant ring are obtained, and the radius R of the circular resonant ring is obtained; R = 4.3400 mm in this embodiment; the designed planar resonator structure is as follows Figure 9 As shown, the effect of this embodiment on the size correction of the circular resonant structure is as follows Figure 10 shown.

[0091] According to the above-mentioned embodiments 2 to 6, it can be seen that if Figure 11 As shown, after the embodiment of the present invention corrects the dimensions of the circular and polygonal resonant structures, the performance test data of the planar resonator structure are shown in Table 1 below.

[0092] Table 1 Performance test data of the planar resonator structure after size correction

[0093]

[0094] As can be seen from the table above, the calculation results of the revised resonant structure size calculation formula are more stable and the frequency deviation is greatly reduced. This shows that the resonant structure size correction method of the present invention has a more accurate correction effect and improves design efficiency.

[0095] like Figure 2 、 Figure 4 、 Figure 6 、 Figure 8 and Figure 10 As shown in the figure, after correction, the simulation error of the resonant frequency of different shapes is significantly lower than before correction. It can be concluded from the variance diagram that after correction, regardless of the number of polygon sides, the stability is higher than before correction.

Claims

1. A method for correcting the size of a resonant structure for detecting the dielectric constant of an LTCC material, characterized in that: The following steps are involved: Step 1: According to the material of the low-temperature co-fired ceramic passive component substrate, the empirical value of the dielectric constant ε of the low-temperature co-fired ceramic passive component substrate of the material at the set initial resonant frequency is given. e (f); and design e (f) corresponding planar resonator structures of circular resonant rings or polygonal resonant rings of different sizes; Step 2: Use HFSS to simulate the planar resonator structures of circular resonant rings or polygonal resonant rings of different sizes designed in Step 1, and obtain the actual resonant frequency through simulation; Step 3: Compare the actual resonant frequency with the initial resonant frequency value to determine a size range for the planar resonator structure. In HFSS, perform a parametric sweep on each dimension within the size range. Simulate the actual resonant frequency corresponding to each dimension within the parametric sweep size range. Find the actual resonant frequency that is consistent with the initial resonant frequency, and use the planar resonator structure size obtained from the parametric sweep corresponding to the actual resonant frequency as the optimized size. Step 4: Divide the optimized dimensions of the planar resonator structure obtained by parametric scanning by the empirical value of the initial dielectric constant ε of the low-temperature co-fired ceramic passive component substrate. e (f) The corresponding resonant structure perimeter, and the correction coefficient K is obtained; Step 5: Use the correction coefficient K obtained in step 4 to correct the perimeter of the polygonal resonant ring or the circular resonant ring, and then correct the size of the planar resonator structure.

2. The size correction method for a resonant structure for detecting the dielectric constant of LTCC materials according to claim 1, characterized in that: Step 4 is as follows: The selected dimension of the planar resonator structure obtained by parametric sweep is the perimeter of the polygonal resonant ring. The perimeter formula of the polygonal resonant ring is: L1=Na In the above formula, L1 is the perimeter of the polygonal resonant ring, N is the number of sides of the polygonal resonant ring, N is a positive integer; a is the side length of the polygon; When a planar resonator structure resonates, the circumference of the electron orbit is an integer multiple of the wavelength of the phase wave after the electromagnetic wave passes through the material. The circumference of the electron orbit is: L2=nλ In the above formula, n is the resonance order, λ is the wavelength of the phase wave after the electromagnetic wave passes through the material, c is the speed of light in vacuum, and the value of c is 3×10 8 m / s, ε e (f) is the empirical value of the initial dielectric constant of the low-temperature co-fired ceramic passive component substrate; f is the set resonant frequency of the planar resonator structure set by circular resonant rings or polygonal resonant rings of different sizes; but: Then the correction coefficient K is: When the number of sides N of the polygonal resonant ring approaches infinity, the polygonal resonant ring is equivalent to the circular resonant ring, then:

3. The size correction method for a resonant structure for detecting the dielectric constant of LTCC materials according to claim 2, characterized in that: Step 5 is as follows: When the planar resonator structure is a polygonal resonant ring, the perimeter of the modified polygonal resonant ring is L1′: L1′=Na=Knλ In the above formula, L1′ is the circumference of the corrected polygonal resonant ring, K is the correction coefficient, n is the resonance order, and c is the speed of light in vacuum, which is 3×10 8 m / s; ε e (f) is the empirical value of the initial dielectric constant of the low-temperature co-fired ceramic passive component substrate.

4. The method for correcting the size of a resonant structure for detecting the dielectric constant of LTCC materials according to claim 2, wherein: Step 5 is as follows: When the planar resonator structure is a circular resonant ring, the circumference of the modified circular resonant ring is L1″: In the above formula, R is the radius of the circular resonant ring.

5. The method for correcting the size of a resonant structure for detecting the dielectric constant of LTCC materials according to any one of claims 2 to 4, characterized in that: Resonance order n=1.

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