A rare earth oxide doped modified zinc silicate ceramic for microwave devices and a method for preparing the same

Abstract

This invention provides a rare-earth oxide-doped modified zinc silicate ceramic for microwave devices and its preparation method, relating to the field of information functional ceramic materials, and can be widely used in microwave tunable devices, especially filters. The ceramic material includes Zn as the main material. 2‑ x SiO 4‑x With modified additives RO rare earth oxides (RO selected from La2O3, CeO2, Pr6O) 11 Zn composed of Nd2O3, Sm2O3, Eu2O3, Gd2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, and Lu2O3 2‑x‑y R y SiO 4‑x Where 0≤x≤0.4, 0≤y≤2. The steps are as follows: ZnO, SiO2, and RO are mixed in a certain proportion, and then subjected to ball milling, drying, sieving, pre-firing, secondary ball milling, granulation, sieving, blanking, and sintering to obtain zinc silicate-based microwave dielectric ceramics. The low-loss, low-dielectric-constant ZnO prepared by this invention... 2‑x‑y R y SiO 4‑x The ceramic solution addresses the technical challenges of high sintering temperature and narrow sintering range in zinc silicate-based microwave dielectric ceramics, which lead to the formation of a second ZnO phase, numerous pores in the sintered product, and a significant decrease in quality factor. It achieves the technical effect of enabling zinc silicate-based microwave dielectric ceramics to be sintered into dense ceramics within a temperature range of 1200–1325℃, with an adjustable dielectric constant ε ranging from 5 to 7.9.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication and electronic ceramic materials technology, specifically relating to a rare earth oxide-doped modified zinc silicate ceramic for microwave devices and its preparation method. Background Technology

[0002] The discovery and development of electromagnetic waves have greatly propelled the progress of human society. Microwave electromagnetic waves, in particular, have made connections between people and between people and things even closer. Mobile communication technology is developing rapidly, with a new generation emerging every decade. Each generation of mobile communication technology pushes the frequency of electromagnetic waves to new heights. While high-frequency electromagnetic waves can carry large amounts of information, they also have drawbacks such as poor obstacle avoidance and susceptibility to attenuation, easily causing signal loss during transmission. To meet the development requirements of 5G / 6G communication technologies, dielectric ceramics with low dielectric constants, high quality factors, and near-zero resonant frequency temperatures have received widespread attention in recent years as key materials for components such as dielectric resonators, dielectric filters, antennas, and substrates. Low dielectric constants improve the transmission efficiency of electrical signals, while high quality factors ensure frequency selectivity during signal transmission.

[0003] Zn 2-x SiO 4-x Dielectric materials possess excellent dielectric properties and have a low dielectric constant ε. r (6.5), high quality factor Q×f (198400GHz) and relatively negative temperature coefficient of resonant frequency τ f (-41.6ppm / ℃). Although its dielectric constant and quality factor are excellent, the preparation method is relatively complex. When using the conventional solid-state reaction method, problems such as the volatilization of ZnO at high temperature and the formation of a second phase of ZnO in the narrow sintering range, as well as the high porosity of the sintered sample, increase the dielectric loss and thus cause a serious decrease in the quality factor.

[0004] To address the aforementioned technical problems, this invention proposes a rare-earth oxide-doped modified zinc silicate ceramic for microwave devices and its preparation method. Summary of the Invention

[0005] The exemplary embodiments will now be described more fully. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of the embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application. Unless otherwise stated, all raw materials, reagents, instruments, and equipment used in this application are commercially available or can be prepared by existing methods.

[0006] In view of the above-mentioned situation of the prior art, the object of the present invention is to provide a rare earth oxide-doped modified zinc silicate ceramic for microwave devices and its preparation method, so as to solve the problem of Zn 2-x SiO 4-x High sintering temperature and narrow sintering range in ceramics can deteriorate dielectric properties.

[0007] The above-mentioned objectives of the present invention are achieved through the following technical solutions.

[0008] A rare-earth oxide-doped modified zinc silicate ceramic for microwave devices and its preparation method, characterized by comprising the following steps:

[0009] (1) Ingredients: ZnO, RO and SiO2 are prepared according to the chemical formula Zn 2-x-y R y SiO 4-x The stoichiometric ratios were used for mixing (RO was selected from La2O3, CeO2, Pr6O). 11 (Nd2O3, Sm2O3, Eu2O3, Gd2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3), where x=0.2, 0≤y≤2, and the gradient is 0.05, with y=0.2 being particularly preferred;

[0010] (2) Mixing: The prepared ZnO, RO and SiO2 are wet ball milled to obtain a slurry. The wet ball milling can be carried out using a polytetrafluoroethylene ball milling jar, zirconia grinding balls and a planetary ball mill. The preferred ball milling aid is deionized water. The volume ratio of powder:zirconia grinding balls:deionized water during ball milling is 1:3~7:8~12, and the ball mill speed is 200~400 r / min.

[0011] (3) Drying: Pour out the slurry after ball milling and put it into an oven to dry until constant weight to obtain a dry mixture. The drying temperature can be 80℃~150℃.

[0012] (4) Pre-calcination: After the mixture is sieved and dispersed, it is pre-calcined at 1000-1200℃ to synthesize Zn. 2-x R x The SiO4 compound powder may specifically include passing a constant weight mixture through a 60-mesh standard sieve, dispersing the mixture, and then placing it in a high-temperature furnace for pre-firing, with the pre-firing temperature preferably being 1050°C.

[0013] (5) Ball milling: the pre-sintered Zn 2-x-y R y SiO 4-x Compound powder is wet ball-milled to form Zn 2-x- y R y SiO 4-x The compound slurry was wet-milled as described in step (2) above;

[0014] (6) Drying: Drying Zn 2-x R x The SiO4 slurry was removed and dried in an oven to constant weight to obtain Zn. 2-x-y R y SiO 4-x The compound powder is dried at a temperature of 80℃ to 150℃ for 12 to 24 hours.

[0015] (7) Granulation and pressing: The dried Zn 2-x-y R y SiO 4-x After fine sieving of the compound powder, a binder is added, and the mixture is thoroughly mixed. Then, after coarse sieving, a powder for compression molding is obtained. Specifically, this may include dried Zn... 2-x-y R y SiO 4-x The compound powder is first passed through a standard sieve of 40-200 mesh, then a binder is added, and the mixture is ground with an agate mortar and pestle to make it evenly mixed with the raw material. Then it is passed through a standard sieve of 40-200 mesh to obtain the raw material for the next pressing molding step. The binder is preferably polyvinyl alcohol (PVA), and the preferred concentration of polyvinyl alcohol is 5-10 wt%. The pressing pressure of the powder is 100-300 MPa, and the holding time is 10-120 seconds.

[0016] (8) Debinding and sintering: The pressed green body is placed in a high-temperature furnace. The furnace heating rate is set to 1~10℃ / min. The temperature is raised to 500-700℃ and held for 1-3 hours, preferably 2 hours. Then the temperature is raised at the same rate. The sintering range is 1200~1325℃ and the holding time is 2-8 hours, preferably 3 hours. Then the temperature is lowered to below 300℃ at a cooling rate of 1~10℃ / min and then cooled naturally with the furnace.

[0017] This invention proposes a rare-earth oxide-doped modified zinc silicate ceramic for microwave devices and its preparation method, using Zn 2-x SiO 4-x The ceramic matrix is ​​used as the substrate, and RO doping is employed (RO is selected from La2O3, CeO2, Pr6O). 11 Zn was synthesized from Nd₂O₃, Sm₂O₃, Eu₂O₃, Gd₂O₃, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, and Lu₂O₃ via a conventional solid-state reaction method. 2-x-y R y SiO 4-x Two-phase composite microwave dielectric ceramics. The two-phase composite method improves the density of the sample, broadens the sintering range of zinc silicate microwave dielectric ceramics, and lowers the sintering temperature of the ceramic sample. Furthermore, the microwave dielectric ceramics prepared by the method of this invention exhibit excellent dielectric properties and low loss. This invention can provide an alternative material for microwave communication components such as resonators and filters, and has broad application prospects.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0019] Figure 1 Zn prepared according to Examples 1 to 15 of the present invention 2-x-y R y SiO 4-x XRD pattern of ceramics.

[0020] Figure 2 Zn prepared according to Example 1 of the present invention 2-x-y R y SiO 4-x SEM images of ceramics. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0022] This invention provides a microwave dielectric ceramic comprising a main crystalline phase, the chemical formula of which is Zn. 2-x-y R y SiO 4-x Where 0≤x≤0.4, 0≤y≤2, it has a low dielectric constant and a negative temperature coefficient of resonant frequency, and its dielectric constant is less than 8, preferably between 5 and 7.9.

[0023] To better understand the purpose, technical solution, and advantages of this invention, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] This invention provides a method for preparing low dielectric constant and low loss microwave dielectric ceramics, characterized in that: the main material Zn 2-x SiO 4-x With modified additives RO rare earth oxides (RO selected from La2O3, CeO2, Pr6O) 11 Zn composed of Nd2O3, Sm2O3, Eu2O3, Gd2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, and Lu2O3 2-x-y R y SiO 4-x Where 0≤x≤0.4, 0≤y≤2, ZnO, RO and SiO2 are arranged according to the chemical formula Zn 2-x R x Zn was synthesized by reacting SiO4 in a stoichiometric ratio using a traditional solid-state reaction method. 2-x R x SiO4 microwave dielectric ceramics. Rare earth oxide doping improves the density of the sample, resulting in the preparation of Zn... 2-x- y R y SiO 4-x It possesses a low dielectric constant and low dielectric loss, and reduces the sintering temperature of ceramic samples.

[0025] Example 1:

[0026] Ingredients: ZnO (99.99%), SiO2 (99.99%) according to chemical formula Zn 2-x-y R y SiO 4-xThe stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the equation, x = 0.2, y = 0.2, and RO is taken from La2O. 3。

[0027] Mixing: The weighed raw materials are placed in a polytetrafluoroethylene ball mill jar, using zirconia as grinding balls and deionized water as a milling aid. Wet milling is performed in a planetary ball mill for 12 hours. The volume ratio of powder to zirconia grinding balls to deionized water is 1:5:10, yielding a slurry-like raw material. In the wet milling step, deionized water is preferred as the dispersant. Using deionized water as a dispersant results in more uniform dispersion and a denser structure in ceramic preparation. Traditionally, alcohol is used as a dispersant, but deionized water is less effective. Alcohol as a dispersant may lead to incomplete reaction of carbonate powder, resulting in the formation of a second phase. Furthermore, the generated carbon dioxide may cause micropores, thus reducing the microwave performance of the material.

[0028] Drying: Pour out the ball-milled slurry and place it in an oven to dry at 100°C until constant weight, to obtain a dried mixture.

[0029] Pre-calcination: The constant-weight mixture is first passed through a 60-mesh standard sieve to disperse it. Then, it is placed in a high-temperature furnace for pre-calcination. The preferred pre-calcination temperature is 1050℃ to synthesize Zn. 2-x-y R y SiO 4-x Ceramic powder.

[0030] Ball milling: the process of grinding pre-sintered Zn 2-x-y R y SiO 4-x The compound powder was added to deionized water and ball-milled for 12 hours at 300 r / min to form Zn. 2-x-y R y SiO 4-x Compound slurry.

[0031] Drying: Zn 2-x R x The SiO4 compound slurry was removed and dried in an oven at 100°C until constant weight, yielding Zn. 2-x- y R y SiO 4-x Compound powder.

[0032] Granulation: The dried Zn 2-x-y R y SiO 4-xThe compound powder is first passed through a 60-mesh standard sieve, and then polyvinyl alcohol (PVA) binder with a concentration of 10 wt% is added. The mixture is ground in an agate mortar and pestle to make it evenly mixed with the raw material, and then passed through a 60-mesh standard sieve to obtain the raw material for the next step of pressing and molding.

[0033] Compression molding: Weigh a certain amount of powder and pour it into a mold. Then, press it in a tablet press at a pressure of 115 MPa for 30 seconds to form a ceramic green body with a diameter of 20 mm and a height of 1.5 mm.

[0034] Debinding and sintering: Place the pressed green body into a high-temperature furnace, set the furnace heating rate to 1~5℃ / min, heat to 600℃ and hold for 2 hours to debind. Then raise the temperature to the corresponding temperature at the same heating rate. The preferred sintering temperature range is 1225℃~1325℃ (the specific sintering temperatures are 1225℃, 1250℃, 1275℃, 1300℃ and 1325℃ respectively), hold for 3 hours, and then cool down to 300℃ at a cooling rate of 1~5℃ / min. Stop the program and allow the furnace to cool down naturally.

[0035] Post-processing and testing of samples: After sintering, the samples are sanded to 3000 grit and then polished, followed by ultrasonic cleaning.

[0036] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1275℃. Above this temperature, the final product will burn out.

[0037] Example 2:

[0038] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x R x The SiO4 is prepared according to its stoichiometric ratio, i.e., Zn 2-x R x In SiO4, x = 0.2, y = 0.1, RO is taken from CeO2 (99.99%), the drying temperature is 100℃, and the temperature is raised to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0039] Similarly, in this example (x = 0.1), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0040] Example 3:

[0041] According to the chemical formula Zn 2-x R xWeigh out ZnO (99.99%) and SiO2 (99.99%) according to their chemical formulas. 2-x-y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from CeO2 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0042] Similarly, in this example (x = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0043] Example 4:

[0044] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the equation, x = 0.2, y = 0.2, and RO is taken from Pr6O. 11 (99.99%), drying temperature is 100℃, heated to 600℃ at a heating rate of 1~5℃ / min, otherwise the same as in Example 1.

[0045] Similarly, in this example (x = 0.2), the sintering temperature can reach up to 1275°C. Above this temperature, the final product will burn out.

[0046] Example 5:

[0047] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-xIn the example, x = 0.2, y = 0.2, RO is taken from Nd2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0048] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1275℃. Above this temperature, the final product will burn out.

[0049] Example 6:

[0050] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x R x In SiO4, x = 0.2, y = 0.2, RO is taken from Sm2O3 (99.99%), the drying temperature is 100℃, and the temperature is raised to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0051] Similarly, in this example (x = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0052] Example 7:

[0053] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from Eu2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0054] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0055] Example 8:

[0056] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from Gd2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0057] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0058] Example 9:

[0059] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In this example, x = 0.2, y = 0.2, RO is taken from Dy2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0060] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0061] Example 10:

[0062] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R ySiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from Ho2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0063] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0064] Example 11:

[0065] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from Er2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0066] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0067] Example 12:

[0068] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from Tm2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0069] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0070] Example 13:

[0071] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0.2, RO is taken from Yb2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0072] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0073] Example 14:

[0074] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-x The stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In this case, x = 0.2, y = 0.2, RO is taken from Lu2O3 (99.99%), the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0075] Similarly, in this example (x = 0.2, y = 0.2), the sintering temperature can reach up to 1300℃. Above this temperature, the final product will burn out.

[0076] Example 15:

[0077] According to the chemical formula Zn 2-x-y R y SiO 4-x Weigh ZnO (99.99%) and SiO2 (99.99%) according to the chemical formula Zn 2-x- y R y SiO 4-xThe stoichiometric ratio of Zn is used for mixing. 2-x-y R y SiO 4-x In the example, x = 0.2, y = 0, the drying temperature is 100℃, and the temperature is increased to 600℃ at a heating rate of 1~5℃ / min. Other conditions are the same as in Example 1.

[0078] Similarly, in this example (x = 0.2, y = 0), the sintering temperature can reach up to 1350℃. Above this temperature, the final product will burn out.

[0079] Figure 1 The XRD patterns of Examples 1-15 are shown. Through XRD analysis, Zn was obtained in all Examples 1-15. 2-x SiO 4-x The ceramic sample exhibits a dominant phase with almost no secondary phase. Combined with... Figure 2 (SEM images of preferred embodiment 1) show that Zn modified with different rare earth elements... 2-x SiO 4-x The samples exhibit good density, uniform and small grain distribution, and a low sintering temperature. Compared to the sintering temperature of Zn₂SiO₄, the sintering temperature of rare earth-doped zinc silicate is reduced by 50-100℃. Meanwhile, in Zn… 2-x-y R y SiO 4-x In the system, the sample still has good dielectric properties, with a dielectric constant of less than 10 and adjustable.

[0080] The preparation method of the present invention uses Zn 2-x SiO 4-x The ceramic matrix is ​​used as the substrate, and RO doping is employed (RO is selected from La2O3, CeO2, Pr6O). 11 Zn was synthesized via a conventional solid-state reaction method by changing the phase composition and content of Nd₂O₃, Sm₂O₃, Eu₂O₃, Gd₂O₃, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, and Lu₂O₃. 2-x R x SiO4 microwave dielectric ceramics were used to lower the sintering temperature of ceramic samples. This improved the sample density, resulting in better Zn content. 2-x R x SiO4 possesses low dielectric constant and low dielectric loss. This invention can provide an alternative material for microwave communication components such as resonators and filters, and has broad application prospects.

[0081] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rare-earth oxide-doped modified zinc silicate ceramic for microwave devices, comprising a main material and modifying additives, characterized in that: The main material Zn 2-x SiO 4-x Zn composed of modified additive RO rare earth oxide 2-x-y R y SiO 4-x Where 0 ≤ x ≤ 0.4, y = 0.2, and the RO is selected from La2O3 and Pr6O. 11 The rare earth oxide-doped modified zinc silicate ceramics, containing Nd₂O₃, Sm₂O₃, Eu₂O₃, Gd₂O₃, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, and Lu₂O₃, comprises the following steps: S1 Ingredients: ZnO, RO and SiO2 in accordance with the chemical formula Zn 2-x-y R y SiO 4-x The ingredients are prepared according to the stoichiometric ratio, where 0 ≤ x ≤ 0.4 and y = 0.2; S2 mixing: The prepared ZnO, RO and SiO2 are wet ball-milled to obtain a slurry; S3 Drying: The slurry is dried to a constant weight to obtain a dried mixture; S4 pre-calcination: After dispersing the mixture, it undergoes a pre-calcination to synthesize Zn. 2-x-y R y SiO 4-x The compound powder, wherein the pre-calcination temperature is 1000-1200℃, the heating rate from room temperature to the pre-calcination treatment is 1-10℃ / min, the holding time is 2-6 h, and the temperature is reduced to 600℃ at 2-10℃ / min and then cooled to room temperature in the furnace; S5 ball milling: This process involves milling pre-sintered Zn... 2-x-y R y SiO 4-x Compound powder is subjected to wet secondary ball milling to form Zn 2-x-y R y SiO 4-x Compound slurry; S6 Drying: Zn 2-x-y R y SiO 4-x The compound slurry was dried to constant weight to obtain Zn. 2-x-y R y SiO 4-x Compound powder; S7 Granulation and Pressing: The dried Zn... 2-x-y R y SiO 4-x After the compound powder is sieved, a binder is added, the mixture is sieved again, and then pressed into a ceramic green body. S8 Debinding Sintering: The ceramic green body is heated to the debinding temperature and held at that temperature to remove the binder. Then it is heated to a high temperature for sintering. After that, it is cooled to below 300°C and then cooled with the furnace. In step S8, the debinding temperature during sintering is 500-700°C and the debinding time is 1-3 hours. The sintering temperature is 1200-1325°C, the heating rate is 1-10°C / min, the holding time is 2-8 hours, and then the temperature is lowered to 300°C at 1-10°C / min. After that, it is cooled with the furnace to room temperature.

2. The rare-earth oxide-doped modified zinc silicate ceramic for microwave devices according to claim 1, characterized in that, In step S1, the purity of ZnO, RO, and SiO2 is 99.0% to 99.99%.

3. A rare-earth oxide-doped modified zinc silicate ceramic for microwave devices according to claim 1, characterized in that, In steps S2 and S5, the wet ball milling uses a polytetrafluoroethylene ball milling jar, zirconia grinding balls, and a planetary ball mill. The ball milling aid is deionized water. During ball milling, the volume ratio of powder to zirconia grinding balls to deionized water is 1:3 to 7:8 to 12. The ball mill speed is 200 to 400 r / min, and the ball milling time is 6 to 24 h.

4. A rare-earth oxide-doped modified zinc silicate ceramic for microwave devices according to claim 1, characterized in that, In steps S3 and S6, the slurry drying temperature is 80℃~150℃, and the time is 12~24h.

5. A rare-earth oxide-doped modified zinc silicate ceramic for microwave devices according to claim 1, characterized in that, Steps S4, S5, and S6 are optional steps, meaning that steps S1-S8 can be completed together, or steps S1, S2, S3, S7, and S8 can be completed together.

6. A rare-earth oxide-doped modified zinc silicate ceramic for microwave devices according to claim 1, characterized in that, The adhesive in step S7 is 5-10 wt% polyvinyl alcohol, using a standard sieve of 40-200 mesh, with a powder pressing pressure of 100-300 MPa and a holding time of 10-120 seconds.

7. An application of the rare earth oxide-doped modified zinc silicate ceramic as described in any one of claims 1 to 6, characterized in that, It is used in the manufacture of microwave devices, including stacked antennas, dielectric antennas, filters, and resonators.

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