A niobium pentoxide-doped zinc borosilicate microcrystalline glass and its preparation method

Abstract

This invention relates to the field of microwave dielectric materials technology, and provides a niobium pentoxide-doped zinc borosilicate microcrystalline glass and its preparation method. This invention reduces the melting and volatilization of boron oxide and the formation of zinc borate by designing a low-boron zinc borosilicate microcrystalline glass formulation; and by introducing niobium pentoxide, utilizing Nb... 5+ The high electric field strength disrupts the original structural units in the glass structure, reconstructs the glass network structure, and thus modulates the dielectric properties of the glass-ceramic. Furthermore, the introduction of niobium pentoxide can regulate the glass crystallization characteristics, resulting in a glass-ceramic with a lower sintering temperature and better density. The results of the embodiments show that the dielectric constant of the niobium pentoxide-doped zinc borosilicate glass-ceramic obtained by sintering at 925℃ for 30 min is in the range of 4.4–6.1, and the dielectric loss is in the range of (0.48–5.36) × 10⁻⁶. ‑3 (between 1MHz)

Description

Technical Field

[0001] This invention relates to the field of microwave dielectric materials technology, and in particular to a niobium pentoxide-doped zinc borosilicate microcrystalline glass and its preparation method. Background Technology

[0002] Low-temperature co-fired ceramic (LTCC) is an important composite material for modern microelectronic packaging and a mature multilayer technology for packaging electronic devices and circuits. Today, with the further miniaturization of electronic devices, there is a need to develop LTCC materials with low dielectric constant and low loss to meet the requirements of high signal propagation speed and high reliability.

[0003] ZnO-B2O3-SiO2 (ZBS) glass-ceramics possess advantages such as low sintering temperature, low dielectric constant, and low dielectric loss, making them a promising LTCC material. Currently, research on ZBS glass-ceramics is limited. Chinese patent CN1389416A discloses a Li2O-doped zinc borosilicate glass-ceramic, in which samples were prepared with a composition of 10–40 wt% ZnO, 2–30 wt% B2O3, 10–80 wt% SiO2, and 0.5–10 wt% Li2O. The dielectric properties were tested, and the resulting glass-ceramic exhibited a dielectric constant less than 5 and a dielectric loss of (0.95–1.12) × 10⁻⁶. -3 (1MHz). However, in this technique, the boron oxide content is high (up to 30wt%). The high boron oxide content is easily volatilized during the melting process, resulting in a lower actual boron oxide content in the sample. This deviation will affect the control of the dielectric properties of the glass-ceramic.

[0004] In summary, as industrial production demands high-frequency communication technology, existing LTCC materials are insufficient to meet these application requirements. There is an urgent need to provide a microcrystalline glass with low boron content and tunable dielectric properties to promote the further development of LTCC materials. Summary of the Invention

[0005] In view of this, the present invention provides a niobium pentoxide-doped zinc borosilicate glass and its preparation method. The niobium pentoxide-doped zinc borosilicate glass provided by the present invention has a low boron content, adjustable dielectric properties, good density, and a low sintering temperature.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] A niobium pentoxide-doped zinc borosilicate glass-ceramic comprises ZnO, B2O3, SiO2, and Nb2O5. Based on a total molar fraction of 100% for ZnO, B2O3, and SiO2, the contents of ZnO, B2O3, and SiO2 are as follows: ZnO 60–70 mol%, B2O3 6–15 mol%, SiO2 25–35 mol%. The amount of Nb2O5 incorporated is 0.5–12 mol% of the total ZnO, B2O3, and SiO2. The main phase of the niobium pentoxide-doped zinc borosilicate glass-ceramic is Zn2SiO4.

[0008] Preferably, the niobium pentoxide-doped zinc borosilicate microcrystalline glass has a dielectric constant of 4.4–6.1 and a dielectric loss of 0.48 × 10⁻⁶ at room temperature and a test frequency of 1 MHz. -3 ~5.36×10 -3 .

[0009] The present invention also provides a method for preparing niobium pentoxide-doped zinc borosilicate microcrystalline glass as described above, comprising the following steps:

[0010] ZnO, H3BO3, SiO2 and Nb2O5 are mixed and heated to melt. The resulting molten glass is then quenched in water to obtain a glass body.

[0011] The glass body was ball-milled to obtain glass powder;

[0012] The glass powder and binder are mixed and then subjected to aging, granulation and pressing to obtain a green blank.

[0013] The green blank is sintered to obtain the niobium pentoxide-doped zinc borosilicate microcrystalline glass; the sintering temperature is 850-950℃ and the holding time is 30-60min.

[0014] Preferably, the heating and melting temperature is 1350–1450°C, and the holding time is 2–4 hours.

[0015] Preferably, the ball milling conditions include: the ball milling medium is deionized water, the grinding balls are zirconia balls, the ball milling speed is 300-450 rpm, and the ball milling time is 6-12 h.

[0016] Preferably, after ball milling, the process further includes sieving and drying the resulting ball milled material.

[0017] Preferably, the adhesive is an aqueous solution of polyvinyl alcohol; the mass fraction of polyvinyl alcohol in the aqueous solution is 3-5%.

[0018] Preferably, the mass ratio of the polyvinyl alcohol aqueous solution to the glass powder is 1:(35-45).

[0019] Preferably, the pressing pressure is 70-100 MPa.

[0020] Preferably, the heating rate to the sintering temperature is 5–10 °C / min.

[0021] This invention provides a niobium pentoxide-doped zinc borosilicate glass-ceramic, comprising ZnO, B2O3, SiO2, and Nb2O5. Based on the total molar fraction of ZnO, B2O3, and SiO2 as 100%, the contents of ZnO, B2O3, and SiO2 are as follows: ZnO 60-70 mol%, B2O3 6-15 mol%, SiO2 25-35 mol%. The amount of Nb2O5 incorporated is 0.5-12 mol% of the total ZnO, B2O3, and SiO2. The main phase of the niobium pentoxide-doped zinc borosilicate glass-ceramic is Zn2SiO4. This invention reduces the melting and volatilization of boron oxide and the formation of zinc borate by designing a low-boron zinc borosilicate glass-ceramic formulation; and by introducing niobium pentoxide, utilizing Nb... 5+ The high electric field strength disrupts the original structural units in the glass structure, reconstructs the glass network structure, and thus regulates the dielectric properties of the microcrystalline glass. Furthermore, the main crystalline phase precipitated in undoped niobium pentoxide zinc borosilicate microcrystalline glass is zinc silicate, but it has poor sinterability and low density. This invention introduces niobium pentoxide to regulate the glass crystallization characteristics, obtaining microcrystalline glass with a lower sintering temperature and better density. The results of the examples show that, after sintering at 925℃ for 30 min, the dielectric constant of the niobium pentoxide-doped zinc borosilicate microcrystalline glass obtained by this invention is in the range of 4.4–6.1, and the dielectric loss is in the range of (0.48–5.36) × 10⁻⁶. -3 (between 1MHz)

[0022] This invention also provides a method for preparing niobium pentoxide-doped zinc borosilicate microcrystalline glass as described above. This invention uses ZnO, H3BO3, SiO2 and Nb2O5 as raw materials. The raw materials used are non-corrosive, not likely to cause harm to the human body, and are environmentally friendly. Furthermore, the preparation process of this invention is simple, with low sintering temperature and short time, which shortens the production cycle and increases production efficiency. Attached Figure Description

[0023] Figure 1 XRD patterns of the glass powders prepared in Examples 1 to 6;

[0024] Figure 2 The DSC curves of the glass powders prepared in Examples 1 to 6 are shown.

[0025] Figure 3 XRD patterns of the microcrystalline glass prepared in Examples 1 to 6;

[0026] Figure 4The dielectric properties of the microcrystalline glass prepared in Examples 1 to 6 are shown. Detailed Implementation

[0027] This invention provides a niobium pentoxide-doped zinc borosilicate glass-ceramic, comprising ZnO, B2O3, SiO2, and Nb2O5. Based on a total molar fraction of 100% for ZnO, B2O3, and SiO2, the contents of ZnO, B2O3, and SiO2 are as follows: ZnO 60–70 mol%, B2O3 6–15 mol%, SiO2 25–35 mol%. The amount of Nb2O5 incorporated is 0.5–12 mol% of the total ZnO, B2O3, and SiO2. The main phase of the niobium pentoxide-doped zinc borosilicate glass-ceramic is Zn2SiO4.

[0028] In this invention, based on the total molar fraction of ZnO, B2O3 and SiO2 being 100%, the content of ZnO is preferably 63-65 mol%, more preferably 63.49 mol%, the content of B2O3 is preferably 8-10 mol%, more preferably 8.02 mol%, and the content of SiO2 is preferably 26-30 mol%, more preferably 28.49 mol%.

[0029] In this invention, the content of Nb2O5 is 0.5 to 12 mol% of the total molar amount of ZnO, B2O3 and SiO2, preferably 0.5 to 6 mol%, more preferably 0.5 mol%, 1 mol%, 2 mol%, 4 mol% or 6 mol%.

[0030] In this invention, ZnO, B2O3 and SiO2 are components of the zinc borosilicate microcrystalline glass matrix, and Nb2O5 is additionally introduced into the formulation of the zinc borosilicate microcrystalline glass matrix. Specifically, B2O3 is introduced as H3BO3, and the other components are introduced as oxides.

[0031] In this invention, the dielectric constant of the niobium pentoxide-doped zinc borosilicate microcrystalline glass is preferably 4.4–6.1 at room temperature and a test frequency of 1 MHz, and the dielectric loss is preferably 0.48 × 10⁻⁶. -3 ~5.36×10 -3 .

[0032] The present invention also provides a method for preparing niobium pentoxide-doped zinc borosilicate microcrystalline glass as described above, comprising the following steps:

[0033] ZnO, H3BO3, SiO2 and Nb2O5 are mixed and heated to melt. The resulting molten glass is then quenched in water to obtain a glass body.

[0034] The glass body was ball-milled to obtain glass powder;

[0035] The glass powder and binder are mixed and then subjected to aging, granulation and pressing to obtain a green blank.

[0036] The green blank is sintered to obtain the niobium pentoxide-doped zinc borosilicate microcrystalline glass; the sintering temperature is 850-950℃ and the holding time is 30-60min.

[0037] This invention involves mixing ZnO, H3BO3, SiO2, and Nb2O5, heating and melting them, and then quenching the resulting molten glass in water to obtain a glass body. In this invention, the purity of ZnO, H3BO3, SiO2, and Nb2O5 is preferably greater than or equal to 99%. The amounts of ZnO, H3BO3, SiO2, and Nb2O5 are preferably determined based on the content of each component in the microcrystalline glass, and can be added according to the theoretical dosage. The mixing is preferably carried out in a three-dimensional mixer, and the mixing time is preferably 1 hour. The heating and melting temperature is preferably 1350–1450°C, more preferably 1400°C, and the holding time for heating and melting is preferably 2–4 hours, more preferably 2–3 hours. After obtaining the molten glass, it is preferably quenched in deionized water.

[0038] After obtaining the vitreous body, the present invention ball mills the vitreous body to obtain glass powder. In the present invention, the ball milling conditions preferably include: the ball milling medium is deionized water, the grinding balls are zirconia balls, the ball milling speed is 300–450 rpm, preferably 400–450 rpm, and the ball milling time is 6–12 h, preferably 8–10 h; the ball milling is preferably carried out in a planetary ball mill; after ball milling, the resulting ball milled material is further dried after sieving; the mesh size of the sieve used for sieving is preferably 500 mesh, the undersize material is collected, and the drying temperature is preferably 80°C.

[0039] After obtaining the glass powder, the present invention mixes the glass powder and a binder, and then sequentially ages, granulates, and presses the mixture to obtain a green blank. In the present invention, the binder is preferably an aqueous solution of polyvinyl alcohol; the mass fraction of polyvinyl alcohol in the aqueous solution is preferably 3-5%, more preferably 4%; the mass ratio of the aqueous solution of polyvinyl alcohol to the glass powder is preferably 1:(35-45), more preferably 1:40; the aging time is preferably 24-30 hours, and the aging temperature is preferably room temperature; after aging, the mixture is preferably sieved before granulation; the present invention has no special requirements for the granulation process, and conditions well known in the art can be used; the pressing pressure is preferably 70-100 MPa; therefore, the green blank is preferably a circular green blank with a diameter of 10 mm and a thickness of 2 mm.

[0040] After obtaining the green blank, the present invention sintersects the green blank to obtain the niobium pentoxide-doped zinc borosilicate microcrystalline glass. In the present invention, the sintering temperature is preferably 850-950℃, more preferably 850-950℃, and most preferably 925℃; the sintering holding time is preferably 30-60 min, more preferably 30 min; and the heating rate to the sintering temperature is preferably 5-10℃ / min. After sintering, it can be cooled in the furnace.

[0041] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0042] Example 1: 63.49 mol% ZnO - 8.02 mol% B₂O₃ - 28.49 mol% SiO₂ microcrystalline glass

[0043] Step 1: Using ZnO, H3BO3, and SiO2 as raw materials (purity ≥ 99%), weigh them and mix them in a three-dimensional mixer for 1 hour. After thoroughly mixing the raw materials, heat them to 1400℃ in a resistance furnace and hold for 2 hours to obtain molten glass. Then pour the molten glass into deionized water and rapidly quench it to obtain the glass body.

[0044] Step 2: Place the glass body in a planetary ball mill for ball milling. The milling media is deionized water, and the grinding balls are zirconia balls. The ball mill speed is 450 rpm, and the milling time is 8 hours. After ball milling, pass the glass through a 500-mesh sieve and dry it in an 80℃ oven to obtain glass powder.

[0045] Step 3: Add a 4wt% polyvinyl alcohol (PVA) aqueous solution to the glass powder, allow it to age, sieve, and granulate to obtain a mixed powder of glass powder and PVA aqueous solution (mass ratio of PVA aqueous solution to glass powder is 1:40). Press the mixed powder on a unidirectional tablet press at a pressure of 100MPa to obtain a Φ10mm×2mm round blank.

[0046] Step 4: Place the green blank in a muffle furnace and heat it to 925℃ at a heating rate of 5℃ / min. Hold the temperature for 30 minutes and then cool it with the furnace to obtain a microcrystalline glass with a composition of 63.49mol%ZnO-8.02mol%B2O3-28.49mol%SiO2, denoted as ZBSN0.

[0047] Example 2: 63.49 mol% ZnO - 8.02 mol% B₂O₃ - 28.49 mol% SiO₂ - 0.5 mol% Nb₂O₅ microcrystalline glass

[0048] Step 1: Using ZnO, H3BO3, SiO2, and Nb2O5 as raw materials (purity ≥ 99%), weigh them and mix them in a three-dimensional mixer for 1 hour. After thoroughly mixing the raw materials, heat them to 1400℃ in a resistance furnace and hold for 2 hours to obtain molten glass. Then pour the molten glass into deionized water and rapidly quench it to obtain the glass body.

[0049] Step 2: Place the glass body in a planetary ball mill for ball milling. The milling media is deionized water, and the grinding balls are zirconia balls. The ball mill speed is 450 rpm, and the milling time is 8 hours. After ball milling, pass the glass through a 500-mesh sieve and dry it in an 80℃ oven to obtain glass powder.

[0050] Step 3: Add a 4wt% polyvinyl alcohol (PVA) aqueous solution to the glass powder, allow it to age, sieve, and granulate to obtain a mixed powder of glass powder and PVA aqueous solution (mass ratio of PVA aqueous solution to glass powder is 1:40). Press the mixed powder on a unidirectional tablet press at a pressure of 100MPa to obtain a Φ10mm×2mm round blank.

[0051] Step 4: Place the green blank in a muffle furnace and heat it to 925℃ at a heating rate of 5℃ / min, hold it at that temperature for 30 minutes, and then cool it with the furnace. This yields a glass-ceramic with a composition of 63.49 mol% ZnO - 8.02 mol% B₂O₃ - 28.49 mol% SiO₂ - 0.5 mol% Nb₂O₅, denoted as ZBSN. 0.5 .

[0052] Example 3: 63.49 mol% ZnO, 8.02 mol% B₂O₃, 28.49 mol% SiO₂, and 1 mol% Nb₂O₅ microcrystalline glass.

[0053] Step 1: Using ZnO, H3BO3, SiO2, and Nb2O5 as raw materials (purity ≥ 99%), weigh them and mix them in a three-dimensional mixer for 1 hour. After thoroughly mixing the raw materials, heat them to 1400℃ in a resistance furnace and hold for 2 hours to obtain molten glass. Then pour the molten glass into deionized water and rapidly quench it to obtain the glass body.

[0054] Step 2: Place the glass body in a planetary ball mill for ball milling. The milling media is deionized water, and the grinding balls are zirconia balls. The ball mill speed is 450 rpm, and the milling time is 8 hours. After ball milling, pass the glass through a 500-mesh sieve and dry it in an 80℃ oven to obtain glass powder.

[0055] Step 3: Add a 4wt% polyvinyl alcohol (PVA) aqueous solution to the glass powder, allow it to age, sieve, and granulate to obtain a mixed powder of glass powder and PVA aqueous solution (mass ratio of PVA aqueous solution to glass powder is 1:40). Press the mixed powder on a unidirectional tablet press at a pressure of 100MPa to obtain a Φ10mm×2mm round blank.

[0056] Step 4: Place the green blank in a muffle furnace and heat it to 925℃ at a heating rate of 5℃ / min. Hold the temperature for 30 minutes and then cool it with the furnace to obtain a microcrystalline glass with a composition of 63.49mol%ZnO-8.02mol%B2O3-28.49mol%SiO2-1mol%Nb2O5, denoted as ZBSN1.

[0057] Example 4: 63.49 mol% ZnO, 8.02 mol% B₂O₃, 28.49 mol% SiO₂, and 2 mol% Nb₂O₅ microcrystalline glass.

[0058] Step 1: Using ZnO, H3BO3, SiO2, and Nb2O5 as raw materials (purity ≥ 99%), weigh them and mix them in a three-dimensional mixer for 1 hour. After thoroughly mixing the raw materials, heat them to 1400℃ in a resistance furnace and hold for 2 hours to obtain molten glass. Then pour the molten glass into deionized water and rapidly quench it to obtain the glass body.

[0059] Step 2: Place the glass body in a planetary ball mill for ball milling. The milling media is deionized water, and the grinding balls are zirconia balls. The ball mill speed is 450 rpm, and the milling time is 8 hours. After ball milling, pass the glass through a 500-mesh sieve and dry it in an 80℃ oven to obtain glass powder.

[0060] Step 3: Add a 4wt% polyvinyl alcohol (PVA) aqueous solution to the glass powder, allow it to age, sieve, and granulate to obtain a mixed powder of glass powder and PVA aqueous solution (mass ratio of PVA aqueous solution to glass powder is 1:40). Press the mixed powder on a unidirectional tablet press at a pressure of 100MPa to obtain a Φ10mm×2mm round blank.

[0061] Step 4: Place the green blank in a muffle furnace and heat it to 925℃ at a heating rate of 5℃ / min. Hold the temperature for 30 minutes and then cool it with the furnace to obtain a microcrystalline glass with a composition of 63.49mol%ZnO-8.02mol%B2O3-28.49mol%SiO2-2mol%Nb2O5, denoted as ZBSN2.

[0062] Example 5: 63.49 mol% ZnO, 8.02 mol% B₂O₃, 28.49 mol% SiO₂, and 4 mol% Nb₂O₅ microcrystalline glass.

[0063] Step 1: Using ZnO, H3BO3, SiO2, and Nb2O5 as raw materials (purity ≥ 99%), weigh them and mix them in a three-dimensional mixer for 1 hour. After thoroughly mixing the raw materials, heat them to 1400℃ in a resistance furnace and hold for 2 hours to obtain molten glass. Then pour the molten glass into deionized water and rapidly quench it to obtain the glass body.

[0064] Step 2: Place the glass body in a planetary ball mill for ball milling. The milling media is deionized water, and the grinding balls are zirconia balls. The ball mill speed is 450 rpm, and the milling time is 8 hours. After ball milling, pass the glass through a 500-mesh sieve and dry it in an 80℃ oven to obtain glass powder.

[0065] Step 3: Add a 4wt% polyvinyl alcohol (PVA) aqueous solution to the glass powder, allow it to age, sieve, and granulate to obtain a mixed powder of glass powder and PVA aqueous solution (mass ratio of PVA aqueous solution to glass powder is 1:40). Press the mixed powder on a unidirectional tablet press at a pressure of 100MPa to obtain a Φ10mm×2mm round blank.

[0066] Step 4: Place the green blank in a muffle furnace and heat it to 925℃ at a heating rate of 5℃ / min. Hold the temperature for 30 minutes and then cool it with the furnace to obtain a microcrystalline glass with a composition of 63.49mol%ZnO-8.02mol%B2O3-28.49mol%SiO2-4mol%Nb2O5, denoted as ZBSN4.

[0067] Example 6: 63.49 mol% ZnO, 8.02 mol% B₂O₃, 28.49 mol% SiO₂, and 6 mol% Nb₂O₅ microcrystalline glass.

[0068] Step 1: Using ZnO, H3BO3, SiO2, and Nb2O5 as raw materials (purity ≥ 99%), weigh them and mix them in a three-dimensional mixer for 1 hour. After thoroughly mixing the raw materials, heat them to 1400℃ in a resistance furnace and hold for 2 hours to obtain molten glass. Then pour the molten glass into deionized water and rapidly quench it to obtain the glass body.

[0069] Step 2: Place the glass body in a planetary ball mill for ball milling. The milling media is deionized water, and the grinding balls are zirconia balls. The ball mill speed is 450 rpm, and the milling time is 8 hours. After ball milling, pass the glass through a 500-mesh sieve and dry it in an 80℃ oven to obtain glass powder.

[0070] Step 3: Add a 4wt% polyvinyl alcohol (PVA) aqueous solution to the glass powder, allow it to age, sieve, and granulate to obtain a mixed powder of glass powder and PVA aqueous solution (mass ratio of PVA aqueous solution to glass powder is 1:40). Press the mixed powder on a unidirectional tablet press at a pressure of 100MPa to obtain a Φ10mm×2mm round blank.

[0071] Step 4: Place the green blank in a muffle furnace and heat it to 925℃ at a heating rate of 5℃ / min. Hold the temperature for 30 minutes and then cool it with the furnace to obtain a microcrystalline glass with a composition of 63.49mol%ZnO-8.02mol%B2O3-28.49mol%SiO2-6mol%Nb2O5, denoted as ZBSN6.

[0072] To further demonstrate the superior effects of the technical solution disclosed in this invention, the microcrystalline glass obtained in Examples 1 to 6 above was tested and characterized. The specific results are analyzed below:

[0073] The XRD patterns of the glass powders prepared in Examples 1 to 6 are as follows: Figure 1 As shown. Figure 1 The results showed that diffraction peaks of the Zn₂SiO₄ phase were observed in the undoped niobium pentoxide sample. With increasing niobium pentoxide content, the diffraction peaks evolved into peaks resembling steam buns, indicating that glass crystallization was suppressed and glass characteristic features became more pronounced. The reason for these phenomena may be due to Nb 5+ A high ion field strength can easily destroy the structural units in glass, thereby inhibiting glass crystallization.

[0074] The DSC curves of the glass powders prepared in Examples 1 to 6 are as follows: Figure 2 As shown, the heating rate during the test was 5℃ / min. From Figure 2 It can be seen that most glass samples have a distinct softening point (T). g ), crystallization initiation temperature (T) c ) and exothermic crystallization peak temperature (T p ). T p This may be related to the formation of Zn₂SiO₄. As the niobium pentoxide content increased from 0.5 mol% to 6 mol%, T g T c T p They all decreased first and then increased.

[0075] The XRD patterns of the microcrystalline glass prepared in Examples 1 to 6 are attached. Figure 3 As shown. Figure 3 The results showed that the ZBSN0 glass-ceramic sample contained Zn2SiO4 and Zn4B6O. 13Crystallization occurred, and the diffraction intensity gradually decreased with increasing Nb₂O₅ content, indicating weakened crystallization. However, with the addition of Nb₂O₅, diffraction peaks of ZnNb₂O₆ were detected, and the diffraction intensity gradually increased, indicating that the crystallization of ZnNb₂O₆ gradually increased.

[0076] The dielectric properties of the microcrystalline glass prepared in Examples 1 to 6 are as follows: Figure 4 As shown, the specific values ​​are listed in Table 1. The test temperature was room temperature and the frequency was 1MHz.

[0077] Table 1 Dielectric property test results

[0078]

[0079] according to Figure 4 As can be seen from the data in Table 1, with the addition of Nb₂O₅, the dielectric constant ε r The overall increase is likely due to the low dielectric constant of Zn₂SiO₄ (ε₀). r Besides the 6.6) crystal, there is also ZnNb2O6 (ε) with a high dielectric constant. r =25) Crystallization. Furthermore, with increasing doping concentration, the crystallinity of ZnNb2O6 increases, thus increasing the dielectric constant. The dielectric loss tanδ initially decreases overall with the addition of Nb2O5, then increases. When the Nb2O5 doping concentration is between 0.5 mol% and 2 mol%, the decrease in dielectric loss may be due to increased sample density at lower Nb2O5 doping concentrations. Conversely, as the Nb2O5 doping concentration increases, the density decreases, and the dielectric loss increases accordingly.

[0080] As can be seen from the above embodiments, this invention reduces the melting and volatilization of boron oxide and the formation of zinc borate by designing a low-boron zinc borosilicate glass formulation. The main crystalline phase precipitated in undoped niobium pentoxide zinc borosilicate glass is zinc silicate, but it has poor sinterability and low density. This invention introduces niobium pentoxide to regulate the glass crystallization characteristics, resulting in a microcrystalline glass with a lower sintering temperature and better density. Compared with other low-temperature co-fired materials, this invention offers adjustable dielectric properties, a simple process, a short production cycle, and is environmentally friendly.

[0081] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A niobium pentoxide-doped zinc borosilicate microcrystalline glass, characterized in that, The composition includes ZnO, B2O3, SiO2, and Nb2O5; based on the total molar fraction of ZnO, B2O3, and SiO2 being 100%, the contents of ZnO, B2O3, and SiO2 are as follows: ZnO 60~70 mol%, B2O3 6~10 mol%, SiO2 25~35 mol%; the amount of Nb2O5 incorporated is 0.5~2 mol% of the total amount of ZnO, B2O3, and SiO2; the main phase of the niobium pentoxide-doped zinc borosilicate microcrystalline glass is Zn2SiO4.

2. The niobium pentoxide-doped zinc borosilicate microcrystalline glass according to claim 1, characterized in that, The niobium pentoxide-doped zinc borosilicate microcrystalline glass has a dielectric constant of 4.9–5.6 and a dielectric loss of 0.48 × 10⁻⁶ at room temperature and a test frequency of 1 MHz. -3 ~2.3×10 -3 .

3. The method for preparing niobium pentoxide-doped zinc borosilicate microcrystalline glass according to claim 1 or 2, characterized in that, Includes the following steps: ZnO, H3BO3, SiO2 and Nb2O5 are mixed and heated to melt. The resulting molten glass is then quenched in water to obtain a glass body. The glass body was ball-milled to obtain glass powder; The glass powder and binder are mixed and then subjected to aging, granulation and pressing to obtain a green blank. The green blank is sintered to obtain the niobium pentoxide-doped zinc borosilicate microcrystalline glass; the sintering temperature is 850~950℃ and the holding time is 30~60min.

4. The preparation method according to claim 3, characterized in that, The heating and melting temperature is 1350~1450℃, and the holding time is 2~4h.

5. The preparation method according to claim 3, characterized in that, The conditions for ball milling include: the ball milling medium is deionized water, the grinding balls are zirconia balls, the ball milling speed is 300~450 rpm, and the ball milling time is 6~12 h.

6. The preparation method according to claim 3 or 5, characterized in that, The process after ball milling also includes sieving and drying the resulting ball milled material.

7. The preparation method according to claim 3, characterized in that, The adhesive is an aqueous solution of polyvinyl alcohol; the mass fraction of polyvinyl alcohol in the aqueous solution is 3-5%.

8. The preparation method according to claim 7, characterized in that, The mass ratio of the polyvinyl alcohol aqueous solution to the glass powder is 1:(35~45).

9. The preparation method according to claim 3, characterized in that, The pressure for compression molding is 70~100MPa.

10. The preparation method according to claim 3, characterized in that, The heating rate to the sintering temperature is 5~10℃ / min.

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