{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T03:39:11Z","timestamp":1772249951647,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,4,10]],"date-time":"2020-04-10T00:00:00Z","timestamp":1586476800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, SiNx\/a-Si\/SiNx caps on conductive coplanar waveguides (CPWs) are proposed for thin film encapsulation of radio-frequency microelectromechanical systems (RF MEMS), in view of the application of these devices in fifth generation (5G) and modern telecommunication systems. Simplification and cost reduction of the fabrication process were obtained, using two etching processes in the same barrel chamber to create a matrix of holes through the capping layer and to remove the sacrificial layer under the cap. Encapsulating layers with etch holes of different size and density were fabricated to evaluate the removal of the sacrificial layer as a function of the percentage of the cap perforated area. Barrel etching process parameters also varied. Finally, a full three-dimensional finite element method-based simulation model was developed to predict the impact of fabricated thin film encapsulating caps on RF performance of CPWs.<\/jats:p>","DOI":"10.3390\/s20072133","type":"journal-article","created":{"date-parts":[[2020,4,13]],"date-time":"2020-04-13T10:41:52Z","timestamp":1586774512000},"page":"2133","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Thin Film Encapsulation for RF MEMS in 5G and Modern Telecommunication Systems"],"prefix":"10.3390","volume":"20","author":[{"given":"Anna","family":"Persano","sequence":"first","affiliation":[{"name":"IMM-CNR, Institute for Microelectronics and Microsystems, National Research Council, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fabio","family":"Quaranta","sequence":"additional","affiliation":[{"name":"IMM-CNR, Institute for Microelectronics and Microsystems, National Research Council, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonietta","family":"Taurino","sequence":"additional","affiliation":[{"name":"IMM-CNR, Institute for Microelectronics and Microsystems, National Research Council, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pietro Aleardo","family":"Siciliano","sequence":"additional","affiliation":[{"name":"IMM-CNR, Institute for Microelectronics and Microsystems, National Research Council, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6462-4814","authenticated-orcid":false,"given":"Jacopo","family":"Iannacci","sequence":"additional","affiliation":[{"name":"CMM-FBK, Center for Materials and Microsystems, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Povo \u2013 Trento, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1016\/j.sna.2018.01.038","article-title":"Internet of Things (IoT); Internet of Everything (IoE); Tactile Internet; 5G \u2014 A (Not So Evanescent) Unifying Vision Empowered by EH-MEMS (Energy Harvesting MEMS) and RF-MEMS (Radio Frequency MEMS)","volume":"272","author":"Iannacci","year":"2018","journal-title":"Sens. Actuators A Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"436","DOI":"10.1016\/j.jksus.2017.06.011","article-title":"RF-MEMS for High-Performance and Widely Reconfigurable Passive Components \u2014 A Review with Focus on Future Telecommunications, Internet of Things (IoT) and 5G Applications","volume":"29","author":"Iannacci","year":"2017","journal-title":"J. King Saud Univ. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1741","DOI":"10.1007\/s00542-016-2829-z","article-title":"Influence of design and fabrication on RF performance of capacitive RF MEMS switches","volume":"22","author":"Persano","year":"2016","journal-title":"Microsyst. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Hilton, A., and Temple, D.S. (2016). Wafer-Level Vacuum Packaging of Smart Sensors. Sensors, 16.","DOI":"10.3390\/s16111819"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"556","DOI":"10.1109\/JMEMS.2002.802903","article-title":"Vacuum Packaging Technology Using Localized Aluminum\/Silicon-to-Glass Bonding","volume":"11","author":"Cheng","year":"2002","journal-title":"J. Microelectromech. Syst."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1109\/JMEMS.2004.825301","article-title":"A Low-Temperature Thin-Film Electroplated Metal Vacuum Package","volume":"13","author":"Stark","year":"2004","journal-title":"J. Microelectromech. Syst."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1016\/j.sna.2007.11.002","article-title":"Thin film encapsulation technology for harms using sacrificial CF-polymer","volume":"145\u2013146","author":"Reuter","year":"2008","journal-title":"Sens. Actuators A Phys."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"448","DOI":"10.1109\/TADVP.2008.2006757","article-title":"A Low-Temperature SU-8 Based Wafer-Level Hermetic Packaging for MEMS Devices","volume":"32","author":"Okoniewski","year":"2009","journal-title":"IEEE Trans. Adv. Packag."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1109\/JMEMS.2011.2170817","article-title":"Mechanical Design and Characterization for MEMS Thin-Film Packaging","volume":"21","author":"Santagata","year":"2012","journal-title":"J. Microelectromech. Syst."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"575","DOI":"10.1007\/s00542-017-3583-6","article-title":"Wafer-level micropackaging in thin film technology for RF MEMS applications","volume":"24","author":"Persano","year":"2018","journal-title":"Microsyst. Technol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"930","DOI":"10.1109\/TCPMT.2015.2402296","article-title":"A Robust Bilayer Cap in Thin Film Encapsulation for MEMS Device Application","volume":"5","author":"Sharma","year":"2015","journal-title":"IEEE Trans. Compon. Packag. Manuf. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"065010","DOI":"10.1088\/0960-1317\/25\/6\/065010","article-title":"Cavity-enhanced sacrificial layer micromachining for faster release of thin film encapsulated MEMS","volume":"25","author":"Lee","year":"2015","journal-title":"J. Micromech. Microeng."},{"key":"ref_13","first-page":"015012","article-title":"PECVD low stress silicon nitride analysis and optimization for the fabrication of CMUT devices","volume":"25","author":"Bagolini","year":"2015","journal-title":"J. Microelectromech. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3581","DOI":"10.1007\/s00542-018-4264-9","article-title":"Out-of-plane deformation and pull-in voltage of cantilevers with residual stress gradient: Experiment and modelling","volume":"25","author":"Persano","year":"2019","journal-title":"Microsyst. Technol."},{"key":"ref_15","unstructured":"Vidojkovic, M. (2011). Configurable Circuits and Their Impact on Multi-Standard RF Front-End Architectures, Technische Universiteit Eindhoven. [1st ed.]."},{"key":"ref_16","unstructured":"(2020, March 18). The Evolution of Mobile Technologies: 1G to 2G to 3G to 4G LTE. Available online: https:\/\/www.qualcomm.com\/documents\/evolution-mobile-technologies-1g-2g-3g-4g-lte."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Santhi, K.R., Srivastava, V.K., SenthilKumaran, G., and Butare, A. (2003, January 6\u20139). Goals of true broad band\u2019s wireless next wave (4G-5G). Proceedings of the IEEE Vehicular Technology Conference (VTC), Orlando, FL, USA.","DOI":"10.1109\/VETECF.2003.1285943"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Halonen, T., Romero, J., and Melero, J. (2003). GSM, GPRS and EDGE Performance: Evolution towards 3G\/UMTS, John Wiley & Sons. [1st ed.].","DOI":"10.1002\/0470866969"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1206","DOI":"10.1109\/ACCESS.2015.2461602","article-title":"A Survey of 5G Network: Architecture and Emerging Technologies","volume":"3","author":"Gupta","year":"2015","journal-title":"IEEE Access"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Sesia, S., Toufik, I., and Baker, M. (2009). LTE \u2013 The UMTS Long Term Evolution: From Theory to Practice, John Wiley & Sons. [1st ed.].","DOI":"10.1002\/9780470742891"},{"key":"ref_21","unstructured":"(2020, March 19). LTE TDD \u2014 The Global Solution for Unpaired Spectrum. Available online: https:\/\/www.qualcomm.com\/documents\/lte-tdd-global-solution-unpaired-spectrum."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1401","DOI":"10.1007\/s11277-015-2997-7","article-title":"SDN and Virtualization-Based LTE Mobile Network Architectures: A Comprehensive Survey","volume":"86","author":"Nguyen","year":"2015","journal-title":"Wirel. Pers. Commun."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Xiang, W., Zheng, K., and Shen, X.S. (2017). 5G Mobile Communications, Springer International Publishing, Cham. [1st ed.].","DOI":"10.1007\/978-3-319-34208-5"},{"key":"ref_24","unstructured":"(2020, March 19). Evolving LTE to Fit the 5G Future. Available online: https:\/\/www.ericsson.com\/en\/reports-and-papers\/ericsson-technology-review\/articles\/evolving-lte-to-fit-the-5g-future."},{"key":"ref_25","unstructured":"(2020, March 19). 5G Network Architecture A High-Level Perspective. Available online: http:\/\/www.huawei.com\/minisite\/hwmbbf16\/insights\/5G-Nework-Architecture-Whitepaper-en.pdf."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1109\/MCOM.2014.6815890","article-title":"Scenarios for 5G mobile and wireless communications: The vision of the METIS project","volume":"52","author":"Osseiran","year":"2014","journal-title":"IEEE Commun. Mag."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1109\/MCOM.2014.6736761","article-title":"Massive MIMO for next generation wireless systems","volume":"52","author":"Larsson","year":"2014","journal-title":"IEEE Commun. Mag."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Hilt, A. (2019). Availability and Fade Margin Calculations for 5G Microwave and Millimeter-Wave Anyhaul Links. MDPI Appl. Sci., 9.","DOI":"10.3390\/app9235240"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1109\/MCOM.2014.6815893","article-title":"Advanced interference management for 5G cellular networks","volume":"52","author":"Nam","year":"2014","journal-title":"IEEE Commun. Mag."},{"key":"ref_30","unstructured":"Wyglinski, A.M., Nekovee, N., and Hou, T. (2009). Cognitive Radio Communications and Networks: Principles and Practice, Academic Press. [1st ed.]."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Irnich, T., Kronander, J., Sel\u00e9n, Y., and Li, G. (2013, January 8\u20139). Spectrum sharing scenarios and resulting technical requirements for 5G systems. Proceedings of the IEEE PIMRC, London, UK.","DOI":"10.1109\/PIMRCW.2013.6707850"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1109\/MCOM.2014.6815897","article-title":"Device-to-device communication in 5G cellular networks: Challenges, solutions, and future directions","volume":"52","author":"Tehrani","year":"2014","journal-title":"IEEE Commun. Mag."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Orsino, A., Gapeyenko, M., Militano, L., Moltchanov, D., Andreev, S., Koucheryavy, Y., and Araniti, G. (2015, January 6\u201310). Assisted Handover Based on Device-to-Device Communications in 3GPP LTE Systems. Proceedings of the IEEE Globecom Workshops, San Diego, CA, USA.","DOI":"10.1109\/GLOCOMW.2015.7414095"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Iannacci, J. (2017). RF-MEMS Technology for High-Performance Passives: The Challenge of 5G Mobile Applications, IOP Publishing. [1st ed.].","DOI":"10.1088\/978-0-7503-1545-6"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"624","DOI":"10.1016\/j.sna.2018.07.005","article-title":"RF-MEMS technology as an enabler of 5G: Low-loss ohmic switch tested up to 110 GHz","volume":"279","author":"Iannacci","year":"2018","journal-title":"Sens. Actuators A Phys."},{"key":"ref_36","unstructured":"Prasad, R. (1997). Surface Mount Technology\u2014Principles and Practice, Springer Science + Business Media. [2nd ed.]."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Lee, Y.C., Cheng, Y.-T., and Ramadoss, R. (2018). MEMS Packaging, World Scientific. [1st ed.].","DOI":"10.1142\/10692"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"434","DOI":"10.1016\/j.sna.2007.08.018","article-title":"Electromagnetic optimization of an RF-MEMS wafer-level package","volume":"142","author":"Iannacci","year":"2008","journal-title":"Sens. Actuators A Phys."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"442","DOI":"10.1016\/j.sna.2007.09.004","article-title":"RF\u2013MEMS wafer-level packaging using through-wafer interconnect","volume":"142","author":"Tian","year":"2018","journal-title":"Sens. Actuators A Phys."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Tian, J., Iannacci, J., Sosin, S., Gaddi, R., and Bartek, M. (2006, January 6\u20138). RF-MEMS wafer-level packaging using through-wafer via technology. Proceedings of the Electronics Packaging Technology Conference (EPTC), Singapore.","DOI":"10.1109\/EPTC.2006.342755"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Iannacci, J., Gaddi, R., and Gnudi, A. (2007, January 8\u201310). Non-linear electromechanical RF model of a MEMS varactor based on veriloga\u00a9 and lumped-element parasitic network. Proceedings of the European Microwave Integrated Circuit Conference (EuMIC), Munich, Germany.","DOI":"10.1109\/EMICC.2007.4412770"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Iannacci, J. (2013). Practical Guide to RF-MEMS, Wiley-VCH. [1st ed.].","DOI":"10.1002\/9783527680856"},{"key":"ref_43","unstructured":"Young, W.C., and Budynas, R.G. (2002). Roark\u2019s Formulas for Stress and Strain, McGraw-Hill. [7th ed.]."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"893","DOI":"10.1149\/1.2113980","article-title":"Influence of deposition temperature, gas pressure, gas phase composition, and RF frequency on composition and mechanical stress of plasma silicon nitride layers","volume":"132","author":"Claassen","year":"1985","journal-title":"J. Electrochem. Soc."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/7\/2133\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:17:09Z","timestamp":1760174229000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/7\/2133"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,4,10]]},"references-count":44,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2020,4]]}},"alternative-id":["s20072133"],"URL":"https:\/\/doi.org\/10.3390\/s20072133","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,4,10]]}}}