可调谐微波电磁材料的制备和性能研究
发布时间：2018-11-13 09:00
【摘要】：随着现代科学技术的不断提高,可调谐微波器件的大量需求,具有可调谐性能的微波电磁材料,如铁电介质材料和铁磁材料,成为重要的研究课题。钛酸锶钡作为微波介电陶瓷重要体系之一,由于其具有介电常数大、介电损耗低、介电可调谐性好等优点,在移相器、可重构天线等可调谐微波器件领域有广泛的应用前景。微波软磁薄膜材料是当今微波集成电路领域的重要材料,它能够有效提高微磁电感的电感量,利用其旋磁性可以制造环行器,利用其磁导率调控可以制造可调谐天线等。软磁薄膜的铁磁共振频率fFMR主要是由其饱和磁化强度4πMs和面内单轴各向异性场HK决定的。各向异性场HK作为外禀参量对制备条件、缺陷等比较敏感,可以更容易的提高1-2个数量级,所以微波金属软磁薄膜的研究主要集中在提高其单轴各向异性场。本论文的主要研究工作有:(1)利用固相合成法制备了不同Ba/Sr比下的Ba_xSr_(1-x)TiO_3陶瓷,研究了x分别为0、0.1、0.2、0.25、0.3、0.325、0.35、0.4、0.425、0.45时BaxSr1-x Ti O3材料的微结构和介电性能,探索了不同Ba/Sr对材料微结构和介电性能的影响。随着Ba含量的增加,样品微波介电常数从286增加到1305,介电损耗从0.624×10~(-3)增加到2.426×10~(-3),介电调谐率最大可达30%。(2)利用固相合成法制备了掺杂30%Mg O、60%Mg O,以及掺杂60%Mg O/0.2%Mn O_2的BST基微波复合陶瓷。研究了掺杂物对不同复合陶瓷微结构和介电性能的影响。随着Mg O含量增加,样品介电常数从1656.3减小到86.1,介电损耗从2.49×10~(-3)增加到4.46×10~(-3);掺杂Mn O2后,介电常数再次减小至83,同时介电损耗也下降至4.06×10~(-3)。原因是Mg O的掺杂会导致样品晶格常数增大,介电常数减小,介电损耗增大,介电调谐率减小。Mn O2掺杂则会环绕在Mg O的表面,从而阻止Mg2+进入BST晶格,使得其晶格常数增大的几率降低。(3)利用磁控溅射成分梯度溅射(CGS)方法,以单晶Si(100)为衬底,生长了约100 nm厚的FeCoB软磁薄。测得CGS-Fe_(70)Co_(30)B的饱和磁化强度4πMS从16.3 k G下降到13.5 k G,单轴各向异性场HK从180.6 Oe增到295.5 Oe,铁磁共振频率f_(FM)R从4.82 GHz增加到5.62 GHz。利用X射线原子吸收谱(XAS)揭示了饱和磁化强度减小主要原因是由于Fe原子和B原子的杂化。
[Abstract]:With the development of modern science and technology, there is a great demand for tunable microwave devices. Microwave electromagnetic materials with tunable properties, such as ferrodielectric materials and ferromagnetic materials, have become an important research topic. Barium strontium titanate (barium strontium titanate) is one of the important microwave dielectric ceramics. Because of its high dielectric constant, low dielectric loss and good dielectric tunability, barium strontium titanate has a wide application prospect in the field of phase shifter, reconfigurable antenna and other tunable microwave devices. Microwave soft magnetic thin film is an important material in the field of microwave integrated circuits. It can effectively improve the inductance of micromagnetoelectric inductance, make circulators with its gyromagnetic properties, and make tunable antennas by using its permeability regulation and so on. The ferromagnetic resonance frequency (fFMR) of soft magnetic thin films is mainly determined by the saturation magnetization of 4 蟺 Ms and the in-plane uniaxial anisotropic field HK. The anisotropic field HK is sensitive to the preparation conditions, defects and so on, and can increase 1-2 orders of magnitude more easily, so the study of microwave metal soft magnetic thin film is mainly focused on improving its uniaxial anisotropic field. The main work of this thesis is as follows: (1) Ba_xSr_ (1-x) TiO_3 ceramics with different Ba/Sr ratios were prepared by solid-state synthesis. The microstructure and dielectric properties of BaxSr1-x Ti O 3 materials with x = 0. 1 / 0. 2 ~ 0. 2 ~ 0. 25 ~ 0. 25 ~ 0. 3 ~ 0. 325 ~ 0. 35 ~ 0. 35 ~ 0. 45 and the effects of different Ba/Sr on the microstructure and dielectric properties of BaxSr1-x Ti / O _ 3 were investigated. With the increase of Ba content, the microwave dielectric constant and dielectric loss increased from 0.624 脳 10 ~ (-3) to 2.426 脳 10 ~ (-3), respectively. The maximum dielectric tuning rate can be up to 30. (2) 30%Mg O _ (60) mg O doped and 60%Mg O/0.2%Mn O _ (2) doped BST based microwave composite ceramics were prepared by solid state synthesis. The effects of dopants on the microstructure and dielectric properties of different composite ceramics were studied. With the increase of Mg O content, the dielectric constant decreased from 1656.3 to 86.1, and the dielectric loss increased from 2.49 脳 10 ~ (-3) to 4.46 脳 10 ~ (-3). After doping Mn O 2, the dielectric constant decreases to 83 and the dielectric loss decreases to 4.06 脳 10 ~ (-3). The reason is that doping of Mg O leads to increase of lattice constant, decrease of dielectric constant, increase of dielectric loss and decrease of dielectric tuning rate. Mn O 2 doping will surround the surface of Mg O, thus preventing Mg2 from entering BST lattice. The probability of increasing lattice constant is decreased. (3) FeCoB soft magnetic thin films with thickness of about 100 nm have been grown by magnetron sputtering component gradient sputtering (CGS) method and single crystal Si (100) substrates. The saturation magnetization of CGS-Fe_ (70) Co_ (30) B decreased from 16.3kG to 13.5 KG, and the uniaxial anisotropic field HK increased from 180.6 Oe to 295.5 Oe,. Ferromagnetic resonance frequency f _ (FM) R increased from 4.82 GHz to 5.62 GHz. X-ray atomic absorption spectroscopy (XAS) shows that the main reason for the decrease of saturation magnetization is the hybridization of Fe atom and B atom.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TQ174.756
，
本文编号：2328630
[Abstract]:With the development of modern science and technology, there is a great demand for tunable microwave devices. Microwave electromagnetic materials with tunable properties, such as ferrodielectric materials and ferromagnetic materials, have become an important research topic. Barium strontium titanate (barium strontium titanate) is one of the important microwave dielectric ceramics. Because of its high dielectric constant, low dielectric loss and good dielectric tunability, barium strontium titanate has a wide application prospect in the field of phase shifter, reconfigurable antenna and other tunable microwave devices. Microwave soft magnetic thin film is an important material in the field of microwave integrated circuits. It can effectively improve the inductance of micromagnetoelectric inductance, make circulators with its gyromagnetic properties, and make tunable antennas by using its permeability regulation and so on. The ferromagnetic resonance frequency (fFMR) of soft magnetic thin films is mainly determined by the saturation magnetization of 4 蟺 Ms and the in-plane uniaxial anisotropic field HK. The anisotropic field HK is sensitive to the preparation conditions, defects and so on, and can increase 1-2 orders of magnitude more easily, so the study of microwave metal soft magnetic thin film is mainly focused on improving its uniaxial anisotropic field. The main work of this thesis is as follows: (1) Ba_xSr_ (1-x) TiO_3 ceramics with different Ba/Sr ratios were prepared by solid-state synthesis. The microstructure and dielectric properties of BaxSr1-x Ti O 3 materials with x = 0. 1 / 0. 2 ~ 0. 2 ~ 0. 25 ~ 0. 25 ~ 0. 3 ~ 0. 325 ~ 0. 35 ~ 0. 35 ~ 0. 45 and the effects of different Ba/Sr on the microstructure and dielectric properties of BaxSr1-x Ti / O _ 3 were investigated. With the increase of Ba content, the microwave dielectric constant and dielectric loss increased from 0.624 脳 10 ~ (-3) to 2.426 脳 10 ~ (-3), respectively. The maximum dielectric tuning rate can be up to 30. (2) 30%Mg O _ (60) mg O doped and 60%Mg O/0.2%Mn O _ (2) doped BST based microwave composite ceramics were prepared by solid state synthesis. The effects of dopants on the microstructure and dielectric properties of different composite ceramics were studied. With the increase of Mg O content, the dielectric constant decreased from 1656.3 to 86.1, and the dielectric loss increased from 2.49 脳 10 ~ (-3) to 4.46 脳 10 ~ (-3). After doping Mn O 2, the dielectric constant decreases to 83 and the dielectric loss decreases to 4.06 脳 10 ~ (-3). The reason is that doping of Mg O leads to increase of lattice constant, decrease of dielectric constant, increase of dielectric loss and decrease of dielectric tuning rate. Mn O 2 doping will surround the surface of Mg O, thus preventing Mg2 from entering BST lattice. The probability of increasing lattice constant is decreased. (3) FeCoB soft magnetic thin films with thickness of about 100 nm have been grown by magnetron sputtering component gradient sputtering (CGS) method and single crystal Si (100) substrates. The saturation magnetization of CGS-Fe_ (70) Co_ (30) B decreased from 16.3kG to 13.5 KG, and the uniaxial anisotropic field HK increased from 180.6 Oe to 295.5 Oe,. Ferromagnetic resonance frequency f _ (FM) R increased from 4.82 GHz to 5.62 GHz. X-ray atomic absorption spectroscopy (XAS) shows that the main reason for the decrease of saturation magnetization is the hybridization of Fe atom and B atom.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TQ174.756
，
本文编号：2328630
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