摘要
随着芯片工作频率的升高,高频封装的需求日益增加。为满足高频单片微波集成电路(MMIC)封装需求,研究并设计了50GHz金锡封口陶瓷四边扁平无引线(CQFN)外壳。金锡封口的优点在于气密性,但频率更高时,封口环引入的焊盘阻抗失配、腔体谐振问题也更加明显。通过优化高频信号焊盘外围匹配结构,使其兼顾屏蔽特性、阻抗匹配及可靠性。同时优化盖板结构,消除了带内腔体谐振。为了评估外壳性能,设计了“印制电路板(PCB)+CQFN外壳+50Ω微带线”一体化结构,该结构在DC~53GHz频带内的实测结果为:回波损耗S_(11)<-13.4dB,插入损耗S_(21)>-1.5dB。完成芯片封装并实测,芯片封装前后带内外性能基本一致。
The demand for high-frequency packaging is increasing with the increase of chip operating frequency.In order to meet the packaging requirements of high-frequency monolithic microwave intergrated circuits(MMICs),a 50 GHz gold-tin sealed ceramic quad flat no-lead(CQFN)package was studied and designed.The advantage of gold-tin sealing is air tightness,but when the frequency is higher,the solder pad impedance mismatching introduced by the sealing ring and cavity resonance problems become more obvious.The peripheral matching structures of high-frequency signal solder pads were optimized to balance shielding characteristics,impedance matching and reliability.At the same time,the cover plate structure was optimized to eliminate in-band cavity resonance.In order to evaluate the package performance,the integrated structure of"printed circuit board(PCB)+CQFN package+50Ωmicrostrip line"was designed.The measured results of structure show that the return loss(S_(11))is less than-13.4 dB and the insertion loss(S_(21))is greater than-1.5 dB within the frequency band of DC-53 GHz.The chip package was completed and measured.The in-band and out-band performances are basically the same before and after chip packaging.
作者
左汉平
王轲
乔志壮
Zuo Hanping;Wang Ke;Qiao Zhizhuang(The 13^(th) Research Institute,CETC,Shijiazhuang 050051,China)
出处
《微纳电子技术》
CAS
2024年第8期25-31,共7页
Micronanoelectronic Technology
