应用于5G微波开关的GaAs pin开关二极管  

GaAs pin Switching Diodes for 5G Microwave Switch

作　　者：陈建星 林伟铭 邱文宗 林伟 林易展 郑伯涛 王淋雨 章剑清 Chen Jianxing;Lin Weiming;Chiu Wentsung;Lin Wei;Lin Yizhan;Zheng Botao;Wang Linyu;Zhang Jianqing(Unicompound Semiconductor Corporation,Putian 351115,China)

机构地区：[1]福联集成电路有限公司,福建莆田351115

出　　处：《半导体技术》2020年第6期460-465,共6页Semiconductor Technology

摘　　要：研制了一种基于6英寸(1英寸=2.54 cm)GaAs外延片的具有高隔离度、低插入损耗的pin开关二极管。采用台面垂直结构以提高器件的工作频率、改善表面击穿电压。提出了采用分步腐蚀法对高台面腐蚀的深度和均匀性进行精准控制。金属互连线使用空气桥互连技术,解决高台面连线困难的问题。p型欧姆接触金属采用Ti/Pt/Au,比接触电阻约为5×10-6Ω·cm2。在无源器件部分制备了电容密度约为597.5 pF/mm2的金属-绝缘体-金属(MIM)电容和方块电阻约为48.5Ω/□的TaN电阻并进行了钝化。该pin开关二极管的开启电压约为1.1 V,反向击穿电压约为25 V。使用该pin二极管设计制备了一款单刀双掷(SPDT)开关,在35 GHz频率下,测得该SPDT开关的隔离度约为28 dB,插入损耗约为1.2 dB,适用于5G微波通信的开关设计制造。A 6-inch(1 inch=2.54 cm)GaAs epitaxial wafer based pin switching diode with high isolation and low insertion loss was developed.A mesa vertical structure was adopted to increase the operating frequency and improve the surface breakdown voltage of the device.A step-by-step etching method was proposed to precisely control the etching depth and uniformity of the high mesa.The air bridge interconnect technology was used in metal interconnect to solve the difficulty of high mesa connection.Ti/Pt/Au was used for the p-type ohmic contact metal to achieve a specific contact resistance of about 5×10-6Ω·cm2.In passive component part,a metal-insulator-metal(MIM)capacitor with a capacitance density of 597.5 pF/mm2 and a TaN resistor with a square resistance of 48.5Ω/□were fabricated and passivated.The pin switching diode has a turn-on voltage of about 1.1 V and a reverse breakdown voltage of about 25 V.A single-pole double-throw(SPDT)switch was designed and fabricated using the pin diodes.At the frequency of 35 GHz,the SPDT switch exhibits an isolation of about 28 dB and an insertion loss of about 1.2 dB,which is suitable for the design and manufacture of 5G microwave communication switch.

关 键 词：GAAS PIN二极管 高台面 空气桥 单刀双掷(SPDT)开关 

分 类 号：TN315.[电子电信—物理电子学]