Sang Uk Son, I. Song, Jeashik Shin, Ho-Soo Park, Jing Cui, Chul-Soo Kim, Duck-Hwan Kim
{"title":"Temperature compensated bulk acoustic wave resonator (BAWR) for near zero temperature coefficient of frequency (TCF)","authors":"Sang Uk Son, I. Song, Jeashik Shin, Ho-Soo Park, Jing Cui, Chul-Soo Kim, Duck-Hwan Kim","doi":"10.23919/EUMC.2012.6459302","DOIUrl":null,"url":null,"abstract":"A bulk acoustic wave resonator (BAWR) is an essential component of RF filters and duplexers in wireless communication devices. The BAWR consists of a piezoelectric layer sandwiched between bottom and top electrodes. Its resonance frequency shifts as an environment temperature changes, normally ranging -25~-30 ppm/ °C, of which phenomenon is referred to temperature coefficient of frequency (TCF). When a resonator has a large TCF value the gap between adjacent bands is reduced and interference occurs. To overcome this problem, a low TCF value is required while maintaining the characteristics such as carrier bandwidth, high quality factor (Q), and high effective coupling coefficient (kt2). In this work, a new BAWR structure with SiO2/SiN layers both on the top electrode and under the bottom electrode enabled TCF of -0.3~-7.8 ppm/°C, Q of 2400, and kt2 of 5.4%, respectively. This BAWR has been applied to transmission filters for LTE Band-7 and Band-25.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":"96 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2012 42nd European Microwave Conference","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.23919/EUMC.2012.6459302","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 1
Abstract
A bulk acoustic wave resonator (BAWR) is an essential component of RF filters and duplexers in wireless communication devices. The BAWR consists of a piezoelectric layer sandwiched between bottom and top electrodes. Its resonance frequency shifts as an environment temperature changes, normally ranging -25~-30 ppm/ °C, of which phenomenon is referred to temperature coefficient of frequency (TCF). When a resonator has a large TCF value the gap between adjacent bands is reduced and interference occurs. To overcome this problem, a low TCF value is required while maintaining the characteristics such as carrier bandwidth, high quality factor (Q), and high effective coupling coefficient (kt2). In this work, a new BAWR structure with SiO2/SiN layers both on the top electrode and under the bottom electrode enabled TCF of -0.3~-7.8 ppm/°C, Q of 2400, and kt2 of 5.4%, respectively. This BAWR has been applied to transmission filters for LTE Band-7 and Band-25.