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报道了一种称作“先进的ＳＩＶＦＥＴ”的ＦＥＴ结构（先进的源区通孔ＦＥＴ）。“ＳＩＶＦＥＴ”（源区通孔ＦＥＴ）￣［１］是一种新型的ＦＥＴ，其每个源电极都通过通孔与４０μｍ厚的背面电镀热沉金属相连接地，以达到减小源寄生电感的目的。为了获得低的热阻，芯片厚度要小达３０μｍ。“先进的ＳＩＶＦＥＴ”的改进结构包含了一种选择隐埋ＰＨＳ（电镀热沉）用以代替背面的厚金层。在这种ＦＥＴ中，由于有源层在器件工作时会产生热量，所以有源层下面的基片厚度设定为３０μｍ，并且在其下面埋入了７０μｍ厚的电镀热沉金属金以改善热阻。为了获得微带线的低损耗和足够的机械强度，芯片其它部分的厚度设定为１００μｍ。该结构提供了更高的功率输出及功率附加效率，并且使芯片的操作更加方便。实验结果显示，当这种１３５０μｍ栅宽的ＦＥＴ处在最大沟道温度（４２．１℃）时，具有极低的热阻（１６℃／Ｗ）。其射频特性为，在Ｖ＿（ｄｓ）＝７Ｖ时，对应于１ｄＢ功率压缩点下的功率输出高达２７．９ｄＢｍ，功率附加效率为３２％；当频率为１８ＧＨｚ时，线性增益为８．３ｄＢ。该器件同时也具有很优异的功率密度，当Ｖ＿（ｄｓ）＝８Ｖ时，其值为０．５４Ｗ／ｍｍ。在机械可靠性方面这种结构也?
A FET structure called an Advanced SIVFET (Advanced Source Via FET) is reported. The “SIVFET” (source via FET) [1] is a new type of FET in which each of the source electrodes is connected to a 40 μm-thick back-plated heat sink metal through vias in order to reduce the source parasitic inductance purpose. In order to obtain low thermal resistance, the chip thickness is as small as 30μm. The improved structure of the Advanced SIVFET includes a thick gold layer that replaces the back side with a buried PHS. In this FET, since the active layer generates heat when the device is in operation, the thickness of the substrate under the active layer is set to 30 μm, and a 70 μm-thick plating heatsink metal is buried under it to improve the heat Resistance In order to obtain low loss and sufficient mechanical strength of the microstrip line, the thickness of other parts of the chip is set to 100 μm. The structure provides higher power output and power efficiency, and make the operation of the chip more convenient. Experimental results show that this 1350μm gate-width FET has an extremely low thermal resistance (16 ° C / W) at the maximum channel temperature (42.1 ° C). Its radio frequency characteristic is that when V_ (ds) = 7V, the power output corresponding to 1dB power compression point is up to 27.9dBm and the power added efficiency is 32%. When the frequency is 18GHz, the linear gain is 8.3dB. The device also has a very good power density, when V_ (ds) = 8V, its value is 0.54W / mm. In the mechanical reliability of this structure also?