Lightweight porous silica foams with extreme-low dielectric permittivity and loss for future 6G wireless communication technologies

作     者：Petra S.Pálvölgyi Daniel Sebők Imre Szenti Eva Bozo Henri Ervasti Olli Pitkänen Jari Hannu Heli Jantunen Marko E.Leinonen Sami Myllymäki Akos Kukovecz Krisztian Kordas Petra S.Pálv(o)lgyi;Daniel Seb(o)k;Imre Szenti;Eva Bozo;Henri Ervasti;Olli Pitk(a)nen;Jari Hannu;Heli Jantunen;Marko E.Leinonen;Sami Myllym(a)ki;Akos Kukovecz;Krisztian Kordas

作者机构：Microelectronics Research UnitFaculty of Information and Electrical EngineeringUniversity of OuluP.O.Box 4500FI-90570OuluFinland Interdisciplinary Excellence CentreDepartment of Applied and Environmental ChemistryUniversity of SzegedRerrich Béla tér 1H-6720SzegedHungary Centre for Wireless CommunicationsUniversity of OuluP.O.Box 4500FI-90570OuluFinland 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2021年第14卷第5期

页      面：1450-1456页

核心收录：

学科分类：080904[工学-电磁场与微波技术] 0810[工学-信息与通信工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080402[工学-测试计量技术及仪器] 0804[工学-仪器科学与技术] 081001[工学-通信与信息系统] 

基　　金：The authors thank Kai Metsäkoivu for the technical assistance and Henrikki Liimatainen for providing us with nanocellulose materials The financial support received partly from EU Interreg Nord-Lapin liitto(project Transparent,conducting and flexible films for electrodes),Academy of Finland(6Genesis Flagship under Grant 318927) University of Oulu(projects Entity and PoC:Ultra-low permittivity and loss porous nanocomposites for future 6G telecommunication),Hungarian National Research,Development and Innovation Office through the projects GINOP-2.3.2-15-2016-00013 and GINOP-2.3.3-15-2016-00010 the Ministry of Human Capacities,Hungary,grant 20391-3/2018/FEKUSTRAT is acknowledged.D.S.is thankful for the János Bolyai Research Scholarship of the Hungarian Academy of Sciences 

主　　题：low-permittivity materials low-loss dielectrics templated sol-gel synthesis silica foams 6G telecommunication 

摘      要：In the next generation wireless communication systems operating at near terahertz frequencies, dielectric substrates with the lowest possible permittivity and loss factor are becoming essential. In this work, highly porous (98.9% ± 0.1%) and lightweight silica foams (0.025 ± 0.005 g/cm3), that have extremely low relative permittivity (εr = 1.018 ± 0.003 at 300 GHz) and corresponding loss factor (tan δ 3 × 10−4 at 300 GHz) are synthetized by a template-assisted sol-gel method. After dip-coating the slabs of foams with a thin film of cellulose nanofibers, sufficiently smooth surfaces are obtained, on which it is convenient to deposit electrically conductive planar thin films of metals important for applications in electronics and telecommunication devices. Here, micropatterns of Ag thin films are sputtered on the substrates through a shadow mask to demonstrate double split-ring resonator metamaterial structures as radio frequency filters operating in the sub-THz band.