Low-loss glass ceramic material applied to LTCC (Low Temperature Co-Fired Ceramic) and preparation method

Abstract

The invention relates to the technical field of electronic ceramic preparation, in particular to a low-loss glass ceramic material applied to LTCC (low temperature co-fired ceramic) and a preparation method thereof.The low-loss glass ceramic material is prepared from CaCO3 with the purity of 99%, Al2O3 with the purity of 99.91% and B2O3 with the purity of 98% according to the mass ratio of CaCO3: 29.47-37.92%; the content of Al2O3 is 9.57%-29.74%; the preparation method comprises the following steps: preparing materials, carrying out ball milling, and carrying out a sintering method. The microwave performance of the material is excellent, the dielectric constant epsilon r is 4-6, the quality factor Q * f is 23605-54699 GHz, the temperature coefficient of resonance frequency tau f is-40 ppm / DEG C to-20 ppm / DEG C, and the material is easy to prepare and has great application and market potential. Therefore, the problem of high loss of the existing dielectric material is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic ceramic preparation, and in particular to a low-loss glass ceramic material applied to LTCC and a preparation method thereof. Background Art

[0002] As the main raw material for electronic components such as filters, oscillators, and resonators, dielectric materials are receiving more and more attention in today's rapidly developing communication equipment. Among them, low dielectric constant dielectric materials can effectively avoid signal delays, and dielectric materials with high quality factors (Q×f) can ensure that the insertion loss is small during application. The resonant frequency temperature coefficient is a parameter that reflects the temperature stability of the material. The closer its value is to 0, the better the temperature stability is, reducing the frequency drift of the device during application.

[0003] With the development of low temperature co-firing technology (LTCC), dielectric materials and electrode materials are co-fired together, which greatly reduces time and economic costs and improves the reliability of integrated devices. Glass ceramics are a new type of dielectric material with low sintering temperature, good chemical stability, high strength and good electrical insulation. In the glass ceramic system, crystallization occurs in the glass grid as the sintering temperature increases. Compared with ceramic materials, glass ceramics have smaller internal grain size, more dense stacking, and generally have excellent microwave dielectric properties. The present invention develops a low-dielectric and low-loss glass ceramic dielectric material with a lower sintering temperature and easy preparation, which can be applied to LTCC and has good market potential. Summary of the invention

[0004] The object of the present invention is to provide a low-loss glass ceramic material for LTCC and a preparation method thereof, aiming to solve the problem of high loss of existing dielectric materials.

[0005] To achieve the above object, in a first aspect, the present invention provides a method for preparing a low-loss glass-ceramic material for LTCC, comprising the following steps:

[0006] Weigh CaCO3, Al2O3 and B2O3 powders according to the mass ratio, add anhydrous ethanol and perform the first wet grinding to obtain powder slurry;

[0007] The powder slurry is placed in a drying oven for drying, sieved, and placed in a lifting furnace for melting to obtain glass;

[0008] Pour the glass into deionized water, cool and dry;

[0009] The dried glass is crushed and then anhydrous ethanol is added for secondary wet grinding to obtain glass powder;

[0010] The glass powder is dried, granulated, and pressed into a green body;

[0011] The green body is sintered to obtain a low-loss glass-ceramic material.

[0012] Among them, in “weighing CaCO3, Al2O3 and B2O3 powders according to the mass ratio, adding anhydrous ethanol and performing the first wet grinding to obtain a powder slurry”, the mass ratio of the mixed powder of the CaCO3, the Al2O3 and the B2O3 to the anhydrous ethanol is 2:1, the duration of the first wet grinding is 4 hours, and the rotation speed is 250r / min.

[0013] Among them, in “the powder slurry is placed in a drying oven for drying, then sieved, and placed in a lifting furnace for melting to obtain glass”, the sieving uses an 80-mesh screen, the melting temperature of the lifting furnace is 1400°C, and the calcination time is 40 minutes.

[0014] Among them, in “crushing the dried glass and adding anhydrous ethanol for secondary wet grinding to obtain glass powder”, the second wet grinding lasts for 6 hours and the rotation speed is 200 r / min.

[0015] Wherein, in “drying the glass powder, granulating it, and pressing it into a green body”, 30% polymethyl methacrylate solution is used as a binder in the granulation process.

[0016] Among them, in "sintering the green body to obtain a low-loss glass-ceramic material", the sintering temperature is 800°C-900°C, and the sintering time is 2h.

[0017] In the second aspect, a low-loss glass-ceramic material for LTCC is provided, which adopts the method for preparing the low-loss glass-ceramic material for LTCC described in the first aspect, and includes CaCO3, Al2O3 and B2O3, and the mass ratios thereof are 29.47%-37.92%; 9.57%-29.74%; 40.78%-52.5%.

[0018] The invention discloses a method for preparing a low-loss glass-ceramic material for LTCC, comprising the following steps: weighing CaCO3, Al2O3 and B2O3 powders according to a mass ratio, adding anhydrous ethanol and performing a first wet grinding to obtain a powder slurry; placing the powder slurry in a drying box for drying, sieving it, and placing it in a lifting furnace for melting to obtain glass; pouring the glass into deionized water for cooling and drying; crushing the dried glass, adding anhydrous ethanol and performing a second wet grinding to obtain glass powder; drying the glass powder, granulating it, and pressing it into a green body; sintering the green body to obtain a low-loss glass-ceramic material. The present invention uses 99% pure CaCO3, 99.91% pure Al2O3 and 98% B2O3, in a mass ratio of CaCO3: 29.47% to 37.92%; Al2O3: 9.57% to 29.74%; B2O3: 40.78% to 52.5%, and performs mixing, ball milling, and sintering to prepare the material. The material has excellent microwave performance: dielectric constant ε r is 4 to 6, the quality factor Q×f is 23605 to 54699 GHz, and the resonant frequency temperature coefficient τ f The temperature is -40 to -20 ppm / ℃, and it is easy to prepare, with great application and market potential, thus solving the problem of high loss of existing dielectric materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, 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 work.

[0020] Figure 1 The present invention provides a flow chart of a method for preparing a low-loss glass ceramic material for LTCC. DETAILED DESCRIPTION

[0021] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0022] See also Figure 1 In a first aspect, the present invention provides a method for preparing a low-loss glass-ceramic material for LTCC, comprising the following steps:

[0023] S1 weigh CaCO3, Al2O3 and B2O3 powders according to the mass ratio, add anhydrous ethanol and perform the first wet grinding to obtain powder slurry;

[0024] The mass ratio of the mixed powder of the CaCO3, the Al2O3 and the B2O3 to the anhydrous ethanol is 2:1, the duration of the first wet grinding is 4 hours, and the rotation speed is 250 r / min.

[0025] Specifically, CaCO3, Al2O3 and B2O3 powders are weighed according to the mass ratio, and anhydrous ethanol is added to perform the first wet grinding to obtain powder slurry.

[0026] S2: drying the powder slurry in a drying oven, sieving it, and melting it in a lifting furnace to obtain glass;

[0027] The sieving adopts an 80-mesh screen, the melting temperature of the lifting furnace is 1400° C., and the calcination time is 40 minutes.

[0028] Specifically, the wet-milled powder slurry is placed in an oven for drying; the dried powder is sieved and placed in a lifting furnace for melting.

[0029] S3: pouring the glass into deionized water, cooling and drying;

[0030] Specifically, the molten glass is poured into deionized water to cool, and then placed in an oven.

[0031] S4: crushing the dried glass and adding anhydrous ethanol to perform secondary wet grinding to obtain glass powder;

[0032] The second wet grinding lasted for 6 hours at a rotation speed of 200 r / min.

[0033] Specifically, the dried glass is crushed, and anhydrous ethanol is added to perform a second wet grinding.

[0034] S5: drying the glass powder, granulating the powder, and pressing the powder into a green body;

[0035] In the granulation process, 30% polymethyl methacrylate solution is used as a binder.

[0036] Specifically, the wet-ground glass powder is dried and granulated, and then pressed into a green body.

[0037] S6: sintering the green body to obtain a low-loss glass-ceramic material.

[0038] The sintering temperature is 800° C.-900° C. and the sintering time is 2 hours.

[0039] Specifically, the obtained ceramic green body is sintered to complete the preparation.

[0040] Embodiment 1:

[0041] The implementation steps are as follows:

[0042] Using CaCO3, Al2O3 and B2O3 powder as raw materials, glass ceramic dielectric material is prepared by sintering method. The specific implementation steps are as follows:

[0043] (1) According to the mass ratio of CaCO3: 37.92%; Al2O3: 9.57%; B2O3: 52.49%, weigh the powder, add anhydrous ethanol with a mass ratio of 1:2, and ball mill for 4 hours at a speed of 250 r / min;

[0044] (2) placing the powder slurry obtained in step (1) into an oven, drying at 70° C. and sieving;

[0045] (3) placing the sieved powder in step (2) into a lifting furnace, melting it at 1400° C., and keeping it warm for 40 min;

[0046] (4) Pour the molten glass obtained in step (3) into deionized water and place it in an oven for drying.

[0047] (5) crushing the glass after drying in step (4), adding anhydrous ethanol with a mass ratio of 1:2 and ball milling for 6 hours at a speed of 200 r / min;

[0048] (6) drying and granulating the glass powder wet-ground in step (5), and pressing the glass powder into a green body;

[0049] (7) Sintering the green body of step (6) at 875° C. for 2 h;

[0050] (8) The microwave dielectric properties of the samples were tested by vector network analyzer. r =5.12, Q×f=54699GHz, τ f =-23.62ppm / ℃. Specific embodiment 2:

[0052] The implementation steps are as follows:

[0053] Using CaCO3, Al2O3 and B2O3 powder as raw materials, glass ceramic dielectric material is prepared by sintering method. The specific implementation steps are as follows:

[0054] (1) According to the mass ratio of CaCO3: 34.62%; Al2O3: 17.47%; B2O3: 47.91%, weigh the powder, add anhydrous ethanol with a mass ratio of 1:2, and ball mill for 4 hours at a speed of 250 r / min;

[0055] (2) placing the powder slurry obtained in step (1) into an oven, drying at 70° C. and sieving;

[0056] (3) placing the sieved powder in step (2) into a lifting furnace, melting it at 1400° C., and keeping it warm for 40 min;

[0057] (4) Pour the molten glass obtained in step (3) into deionized water and place it in an oven for drying.

[0058] (5) crushing the glass after drying in step (4), adding anhydrous ethanol with a mass ratio of 1:2 and ball milling for 6 hours at a speed of 200 r / min;

[0059] (6) drying and granulating the glass powder wet-ground in step (5), and pressing the glass powder into a green body;

[0060] (7) Sintering the green body of step (6) at 875° C. for 2 h;

[0061] (8) The microwave dielectric properties of the prepared samples were tested by network analyzer, ε r =4.94, Q×f=43289GHz, τ f =-30.72ppm / ℃.

[0062] Embodiment 3:

[0063] The implementation steps are as follows:

[0064] Using CaCO3, Al2O3 and B2O3 powder as raw materials, glass ceramic dielectric material is prepared by sintering method. The specific implementation steps are as follows:

[0065] (1) Weigh the powder according to the mass ratio of CaCO3: 29.47%, Al2O3: 29.74%, B2O3: 40.78%, add anhydrous ethanol with a mass ratio of 1:2 and ball mill for 4 hours at a speed of 250 r / min;

[0066] (2) placing the powder slurry obtained in step (1) into an oven, drying at 70° C. and sieving;

[0067] (3) placing the sieved powder in step (2) into a lifting furnace, melting it at 1400° C., and keeping it warm for 40 min;

[0068] (4) Pour the molten glass obtained in step (3) into deionized water and place it in an oven for drying.

[0069] (5) crushing the glass after drying in step (4), adding anhydrous ethanol with a mass ratio of 1:2 and ball milling for 6 hours at a speed of 200 r / min;

[0070] (6) drying and granulating the glass powder wet-ground in step (5), and pressing the glass powder into a green body;

[0071] (7) Sintering the green body of step (6) at 875° C. for 2 h;

[0072] (8) The microwave dielectric properties of the samples were tested by vector network analyzer. r =5.25, Q×f=45898GHz, τ f =-30.51ppm / ℃.

[0073]

[0074] In the second aspect, a low-loss glass-ceramic material for LTCC is provided, which adopts the method for preparing the low-loss glass-ceramic material for LTCC described in the first aspect, and includes CaCO3, Al2O3 and B2O3, and the mass ratio thereof is 29.47%-37.92%: 9.57%-29.74%: 40.78%-52.5%.

[0075] In this embodiment, the low-loss glass-ceramic material comprises components in a mass ratio of CaCO3: 29.47% to 37.92%; Al2O3: 9.57% to 29.74%; B2O3: 40.78% to 52.5%, and is prepared by a sintering method.

[0076] The above disclosure is only a preferred embodiment of the low-loss glass-ceramic material and preparation method for LTCC of the present invention. Of course, this cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for preparing a low-loss glass-ceramic material for LTCC, characterized in that: The following steps are involved: Weigh CaCO3, Al2O3 and B2O3 powders according to the mass ratio, add anhydrous ethanol and perform the first wet grinding to obtain powder slurry; The powder slurry is placed in a drying oven for drying, sieved, and placed in a lifting furnace for melting to obtain glass; Pour the glass into deionized water, cool and dry; The dried glass is crushed and then anhydrous ethanol is added for secondary wet grinding to obtain glass powder; The glass powder is dried, granulated, and pressed into a green body; The green body is sintered to obtain a low-loss glass-ceramic material.

2. The method for preparing a low-loss glass-ceramic material for LTCC according to claim 1, characterized in that: In "weighing CaCO3, Al2O3 and B2O3 powders according to the mass ratio, adding anhydrous ethanol and performing the first wet grinding to obtain a powder slurry", the mass ratio of the mixed powder of CaCO3, Al2O3 and B2O3 to the anhydrous ethanol is 2:1, the duration of the first wet grinding is 4 hours, and the rotation speed is 250r / min.

3. The method for preparing a low-loss glass-ceramic material for LTCC according to claim 1, characterized in that: In "the powder slurry is placed in a drying oven for drying, then sieved, and placed in a lifting furnace for melting to obtain glass", an 80-mesh screen is used for sieving, the melting temperature of the lifting furnace is 1400°C, and the calcination time is 40 minutes.

4. The method for preparing a low-loss glass-ceramic material for LTCC according to claim 1, characterized in that: In “crushing the dried glass and adding anhydrous ethanol for secondary wet grinding to obtain glass powder”, the second wet grinding lasts for 6 hours at a speed of 200 r / min.

5. The method for preparing a low-loss glass-ceramic material for LTCC according to claim 1, characterized in that: In "drying the glass powder, granulating it, and pressing it into a green body", a 30% polymethyl methacrylate solution is used as a binder during the granulation process.

6. The method for preparing a low-loss glass-ceramic material for LTCC according to claim 1, characterized in that: In "sintering the green body to obtain a low-loss glass-ceramic material", the sintering temperature is 800° C.-900° C., and the sintering time is 2 hours.

7. A low-loss glass-ceramic material for LTCC, comprising the method for preparing a low-loss glass-ceramic material for LTCC according to any one of claims 1 to 6, characterized in that: It includes CaCO3, Al2O3 and B2O3, and the mass ratio thereof is 29.47%-37.92%: 9.57%-29.74%: 40.78%-52.5%.

Images